SDA Series Stealth Digital Analyzer Operation Manual 6510-00-0442, Rev D May 2001
Notice Every effort was made to ensure that the information in this document was accurate at the time of printing. However, information is subject to change without notice, and Acterna reserves the right to provide an addendum to this document with information not available at the time that this document was created. Copyright © Copyright 2001 Acterna, LLC. All rights reserved. Acterna, The Keepers of Communications, and its logo are trademarks of Acterna, LLC.
Fe de r al Co m m uni ca t i on s Co m m i s sio n ( F CC ) N o t i c e This product was tested and found to comply with the limits for a Class A digital device, pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference when the equipment is operated in a commercial environment.
Important safety instructions The following table defines safety terms. Failure to observe these precautions while using the Stealth Digital Analyzer violates the intended use of this product. Safety definitions Term Description DANGER Indicates an imminently hazardous situation which, if not avoided, will result in death or serious injury. WARNING Indicates a potentially hazardous situation which, if not avoided, could result in death or serious injury.
9 Do not attempt to service this product yourself, as opening or removing covers may expose you to dangerous, high voltage points and other hazards. Refer all servicing to qualified service personnel. 10 CAUTION: Danger of explosion if battery is incorrectly replaced. Replace only with Acterna P/N 1118-00-0358. Dispose of used batteries according to the manufacturer’s instructions.
Contents Preface About the Manual............................................................................................ xxi Section I Introduction ................................................................................. xxi Section II Field Units.................................................................................. xxi Section III Headend Units ........................................................................ xxiii Section IV Appendices ....................................
Contents Chapter 2 Description and Basic Operation Introduction .........................................................................................................9 User Interface Elements....................................................................................10 The Navigator Interface.................................................................................10 Navigator Tabs and Icons ........................................................................11 Key Controls..........
Contents Editable Parameters .................................................................................46 Configuring a Digital Carrier...................................................................49 Configuring for Inverted Spectrum..........................................................50 Configuring a QAM Digital Stream Channel ..........................................51 Inverted Spectrum Features .....................................................................
Contents Reverse SWEEP Screens .........................................................................85 Reverse Frequency Screen .......................................................................86 Reverse Level Screen...............................................................................86 Reverse Noise Screen ..............................................................................87 Reverse Noise Level Screen ....................................................................
Contents Audio Carriers........................................................................................116 LEVEL Submenu...................................................................................117 FREQUENCY Submenu .......................................................................117 TILT Submenu.......................................................................................118 LIMIT Submenu ....................................................................................
Contents Chapter 9 Digital Analysis (QAM View OPT4) Introduction .....................................................................................................149 Quick Start .......................................................................................................150 Selecting a Digital Analysis Mode ..............................................................150 Using the Navigator Menu.....................................................................
Contents Decision Boundaries ..............................................................................166 Common Impairment Types ..................................................................167 QAM Modulation and Symbol Rates ....................................................169 Modulation Error Ratio (MER) .............................................................169 Bit Error Rate (BER) .............................................................................169 Basic Operation ......
Contents Chapter 11 Files Introduction .....................................................................................................197 Storing Files .....................................................................................................198 Viewing and Printing Files .............................................................................200 Sweep References.............................................................................................201 Overlay Mode..............
Contents Measurement Mode Selection Keys ............................................................218 Support Mode Selection Keys .....................................................................220 Diamond Keys .............................................................................................220 Alphanumeric Entry Keys ...........................................................................220 Alpha Entry Mode............................................................................
Contents Using Auto Test................................................................................................248 How To Create, Edit, and Delete Test Locations ........................................249 How To Perform An Auto Test ...................................................................252 Auto Test Location ................................................................................253 Auto Test Characteristics ....................................................................
Contents Reverse Sweep Setup...................................................................................288 Enabling Reverse Sweep (SDA-5500)...................................................288 Setting the Forward Telemetry Frequency (SDA-5510) .......................289 Setting the Forward Telemetry Level (SDA-5510) ...............................289 Setting the Reverse Telemetry Frequency (SDA-5500 and SDA-5510) ..................................................................
Contents Forward Balancing and Sweeping ...............................................................312 Common Forward Sweep Problems ............................................................313 Standing Waves .....................................................................................313 Spikes.....................................................................................................313 No Communication ..............................................................................
Contents FCC Title 47 Code of Federal Regulations, Subpart K, Section 76.605(a).335 Audio/Video Tests [76.605(a)(2)] .........................................................335 24-hour Variation Test [76.605(a)(3,4,5)] .............................................335 In-Channel Sweeping [76.605(a)(6)] .....................................................336 CNR & Distortions [76.605(a)(7,8)]......................................................337 Terminal Isolation [76.605(a)(9)] ........................
Contents Measurable QAM Ingress: ....................................................................350 Channel Bandwidth:...............................................................................350 Power Source: ........................................................................................351 Appendix C Status Indicators and Icons Status Indicators...........................................................................................353 Soft Key Icons ................................
Preface The Stealth Digital Analyzer (SDA) is the new base platform for Acterna’s family of signal analysis and sweep meters. This manual will guide you through the theory and operation of the SDA headend and field units, providing in-depth, step-by-step configuration, operation, and feature descriptions. ABOUT THE MANUAL Section I Introduction Chapter 1 introduces you to the new SDA family of CATV test equipment.
Preface: About the Manual Chapter 4, "Field Sweeping with the SDA-5000," begins with coverage of test point compensation and how to configure your SDA-5000. Sweep configuration is covered in detail, after which you learn how to connect to amplifier test points and how to conduct forward, reverse, sweepless, and loopback sweeps. This chapter also describes reverse amplifier alignment.
Preface: About the Manual Section III Headend Units Chapter 13, "Description and Basic Operation of the SDA-5500 and SDA5510," describes the user interface and basic modes of operation for the SDA headend units (SDA-5500 and SDA-5510). You also learn basic configuration procedures and what you need to print files and screen shots. Chapter 14, "SDA-5500/SDA-5510 Sweep Configuration," shows you how to configure the SDA-5500 for forward sweep and for reverse sweep.
Preface: About the Manual Additional, important information appears throughout the manual in the form of Tips, Notes, Cautions, and See Also references: NOTE: Notes provide additional information related to the text. They are designed to increase your understanding of the subject matter. TIP: Tips suggest an action (an alternative method or shortcut) you can perform to help make the related procedure easier or quicker. They are designed to show you how to increase your efficiency.
Chapter 1 The SDA Family INTRODUCTION The Stealth Digital Analyzer (SDA) cable network measurement tools test a wide range of critical parameters, helping you prove and maintain your system’s performance. Advanced features include tools to support preventative maintenance programs for improving network quality.
The SDA Family: Introduction NOTE: One benefit of the SDA products is the increased sweep speed provided by the new SDA Stealth Sweep and SDA Transmit operating modes. 1 Keep in mind that in order to take advantage of these new features, you must be using SDA equipment both in the headend (SDA-5500 or SDA-5510) and in the field (SDA5000).
The SDA Family: Field Unit (SDA-5000) FIELD UNIT (SDA-5000) The SDA field receivers conduct a battery of signal level measurements, including a full scan of the cable spectrum to 1 GHz, in addition to performing sweep reception. A proprietary digital signal processing (DSP) technique measures hum and carrier-to-noise (C/N) ratio on modulated carriers. The receivers are streamlined, hand-held instruments weighing approximately 7.5 pounds.
The SDA Family: Field Unit (SDA-5000) • Observe noise signals clearly with the built-in pre-amp. Instead of needing to guess about a signal that is just above the noise floor, the built-in pre-amp allows you to clearly see and diagnose noise 1 • Easily see the difference between meter-induced intermodulation and system intermodulation and CPD (common path distortion).
The SDA Family: Headend Units (SDA-5500 and SDA-5510) measurements with remote (PathTrak System/headend) spectrum measurements.
The SDA Family: Headend Units (SDA-5500 and SDA-5510) areas. In addition to generating the sweep test signal, the SDA-5500 continuously monitors the system carriers. It sends headend level readings to the field receiver with every sweep update. In this way, any headend level changes are compensated for by the receiver, maintaining measurement accuracy. 1 Sweep response measurements won’t be affected by changing signal levels in the headend.
The SDA Family: Options its forward telemetry, so reverse telemetry need not be received to check the reverse ingress condition. 1 Reverse Sweep Alignment Reverse sweep alignment provides an optimum view of the frequency response in the unoccupied reverse spectrum, leaving nothing to chance. A reverse sweep can uncover mismatch problems that reveal themselves as standing waves or as diplex filter roll-offs that can severely hamper the carriage of services in the reverse band.
The SDA Family: Options 1 • SDA-OPT4B: 64/256 QAM, DVS-031, ITU-T J.
Chapter 2 Description and Basic Operation INTRODUCTION This chapter introduces you to the SDA-5000. The user interface is covered first, beginning with the redesigned Navigator menu, followed by an explanation of the buttons and keys on the front panel. Covered next are the unit’s operational modes, including level measurements, sweep, proof-ofperformance measurements (including QAM analysis), the spectrum analysis tool, and compatibility with Acterna’s PathTrak performance monitoring system.
Description and Basic Operation: User Interface Elements USER INTERFACE ELEMENTS The SDA-5000 has two primary user interface elements, the Navigator (shown in Fig. 2-1), and the traditional key controls (shown in Fig. 2-2). The Navigator Interface 2 The Navigator is an easy to use self-guided graphical user interface. It can be displayed at any time by pressing the Nav support key (see Fig. 2-2).
Description and Basic Operation: User Interface Elements 2 Fig. 2-1 The SDA-5000 Navigator Interface Showing the Files and Configure Tab NOTE: If you’re having trouble reading the screen, there are two adjustments you can make: • Adjust screen contrast by pressing the Function key (the green key in the lower right corner of the unit), then the 9 yz key to call up the contrast slider. Use the diamond keys to make the desired adjustment.
Description and Basic Operation: User Interface Elements Files and Configure tab Config .......... page 22 Testpoint ...... page 60 View ............. page 200 Info............... page 32 2 Sweep & Spectrum tab Sweep.......... page 64 Spectrum ..... page 131 PathTrak ...... page 141 Align............. page 90 Modem C/N . page 121 12 RF Measure tab Level..............page 110 Tilt..................page 112 Scan ..............page 115 C/N ................page 119 Hum...............page 124 Mod ............
Description and Basic Operation: User Interface Elements Arrows are displayed for one-hand convenience Soft Keys Soft Keys Soft Icons Measurement Mode Keys Support Keys Diamond Keys Alphanumeric Keypad Enter Key Function Key Power On/Off Fig. 2-2 The SDA-5000 Key Controls Key Controls There are five groups of keys that control the SDA field units (see Fig. 2-2): • Eight soft keys. In many cases, icons that represent soft key functions are displayed in the LCD next to the soft key.
Description and Basic Operation: User Interface Elements • Three support mode keys: Nav Test • Nav calls up the Navigator menu. • Test accesses the AUTOTEST top-level menu. • PathTrak enables PathTrak functions. (This requires that your unit has OPT3, PathTrak Field View.) 2 • Four diamond keys for scrolling menu items, cursors, values, and so on. • A power button • A sixteen button alphanumeric keypad. Soft Keys Soft keys enable you to access a set of up to eight programmable functions at a time.
Description and Basic Operation: User Interface Elements Analysis (QAM View OPT4), has more information about these keys. • Press LEVEL to check the audio and video levels of a channel simultaneously, or to check a specific frequency. • To balance pilot levels, press TILT. Nine selected video carrier levels are displayed. • Press SCAN to see absolute carrier levels on a bar graph. All carriers are displayed. • Press SWEEP to test CATV system frequency response.
Description and Basic Operation: User Interface Elements Alphanumeric Keypad The alphanumeric keypad is augmented with green icons above each key (see Fig. 2-4). The functions represented by these icons are selected or activated by first pressing the green Function key at the lower right of the keypad (see Fig. 2-2), then the key for the desired function. The alphanumeric keys are used to 2 • Enter numeric values 0 through 9.
Description and Basic Operation: Basic Modes of Operation OPT port IN port DIGI port 2 Fig. 2-5 Top View of the SDA-5000 Showing the Three Cable Connection Ports Cable Connection Ports SDA units have up to three cable connection ports (see Fig. 2-5). The IN port allows you to connect the instrument to the cable system. When connected, you can perform sweep operations, standard analog measurements, and digital carrier average power measurements.
Description and Basic Operation: Basic Modes of Operation LEVEL mode presents a detailed display about a single channel. Video and audio levels are displayed both in bar graph and in numeric form. The delta between audio and video level is also computed. When a digital channel is measured, DigiCheck power measurement algorithms are used to accurately read continuous digital carrier levels across the entire selected channel. 2 TILT mode displays level variations of selected carriers throughout the band.
Description and Basic Operation: Basic Modes of Operation create a sweep response without injecting any sweep pulses. This guarantees that no subscriber interference will result from your sweep testing. • SDA sweep: SDA sweep operates identically to Stealth sweep, but it is much faster! It is also critical to note that, for SDA sweep to work, you must be using SDA equipment both in the headend and in the field.
Description and Basic Operation: Basic Modes of Operation service and in-channel. This allows you to measure the performance customers really experience, all without any service interruption. Carrier-to-noise is measured using an advanced “quiet line” algorithm. The meter searches for a line of video with no active signal (this typically happens on one or more lines during vertical sync of an analog video channel).
Description and Basic Operation: Basic Modes of Operation Spectrum Analysis The SDA-5000 features an advanced spectrum analysis capability. This is a simple but extensive tool for tracking down hard-to-find problems in the cable network. The following list describes the features of this tool: The spectrum analyzer works over the entire 5 MHz to 1 GHz frequency range. Tuning can be by channel or by frequency. Several convenient frequency spans are available, from 3 to 50 MHz.
Description and Basic Operation: Configuring the SDA-5000 to toggle between the Local and Remote traces to compare measurement data so you can quickly determine if an ingress problem exists, and if it does, you can isolate its source. See Also ½ Chapter 8, PathTrak Field View (OPT3), discusses the PathTrak Mode in detail. 2 CONFIGURING THE SDA-5000 This section describes the configuration options you access from the CONFIGURE menu.
Description and Basic Operation: Configuring the SDA-5000 2 Fig. 2-6 The CONFIGURE Menu Global Configuration Selecting the GLOBAL option calls up the menu shown in Fig. 2-7. This menu contains twelve items, described in the list that follows. • Operator Name: Enter your name, which will appear in the header section of the Auto Test report (see “Auto Test Results” in Chapter 10, Automatic Test). • Contrast Level: Adjust the contrast level of the LCD to the desired level.
Description and Basic Operation: Configuring the SDA-5000 2 Fig. 2-7 The GLOBAL Menu • Backlight Time-out Period: You can also conserve battery life using the screen backlight’s automatic time-out. The time-out period is programmable: Always Off, 5 sec, 10 sec, or Always On. (You can turn the backlight on or off manually at any time by pressing the Function key twice.) • Time: Use the numeric entry keys to enter the time in HH:MM:SS format.
Description and Basic Operation: Configuring the SDA-5000 The required serial printer configuration is as follows: • Baud rate consistent with SDA-5000 Receiver (9600 or 19.2K recommended) • 8 data bits • 1 stop bit • No parity 2 • Flow control - hardware handshaking Printing to a parallel printer requires a serial-to-parallel converter such as the one manufactured by Black Box Corp. (Phone 412-746-5500). The setup is the same as the serial printer configuration.
Description and Basic Operation: Configuring the SDA-5000 2 Fig. 2-8 The MEASUREMENT Menu NOTE: The Test Point Compensation item has been moved to another menu, TESTPOINT, accessible from the Navigator or by pressing the Function and 7 stu keys. • Temperature Units: Select the desired temperature units (degrees Celsius or degrees Fahrenheit). • Signal Level Units: Select the units to be used for checking signal power levels (dBmV, dBuV, and dBm).
Description and Basic Operation: Configuring the SDA-5000 the calibration, select C/N calibration and press the Enter key. To get a valid measurement, the program prompts you to be sure that no cable is connected to the RF IN connector. After the measurement is verified, press the OK soft key to perform the calibration. When the calibration is complete, the screen displays the noise floor, expressed in the currently selected units (e.g. dBmV).
Description and Basic Operation: Configuring the SDA-5000 • Delete unused channels • Build sweep points • Specify Auto Test measurements • Edit Limits • Edit Digital Limits 2 • Remotely copy a plan from another instrument See Also ½ Chapter 3, Channel Plans, covers these options in detail. Sweep Configuration The SWEEP option of the CONFIGURE main menu enables you to establish the operating parameters that you want for a specific sweeping application.
Description and Basic Operation: Configuring the SDA-5000 See Also ½ Chapter 8, PathTrak Field View (OPT3), covers PathTrak configuration and operation in detail. Diagnostics From the DIAGNOSTICS menu shown in Fig. 2-9, you can reset the instrument to original factory configuration, test the LCD, or, when applicable, check the field unit’s internal transmitter functions.
Description and Basic Operation: Configuring the SDA-5000 2 Fig. 2-10 The DISPLAY TEST Screen • Transmitter Diagnostics: Highlight this option and press the Enter key to access the internal transmitter diagnostic features shown in Fig. 2-11. Fig. 2-11 The Transmitter Diagnostics Screen • Transmitter On/Off: When turned on, this feature provides a CW RF signal that can be used for troubleshooting or during installation. The signal is present only when the diagnostics screen is displayed.
Description and Basic Operation: Configuring the SDA-5000 • Transmitter Attenuator: Use the up and down diamond keys to enter the amount of attenuation for the CW transmitted signal to a maximum of 30 dB in 2.0 dB increments. CAUTION ! If you set the transmitter test frequencies too close to the CATV carrier while you’re connected to the CATV system, you can create significant interference to the subscribers. 2 • Transmitter Frequency: Enter the frequency for the transmitted signal to the nearest 0.
Description and Basic Operation: Configuring the SDA-5000 2 Fig. 2-13 Calibrate Error (Missing Jumper Cable) If your connections are correct and you still get the error screen, contact an authorized Acterna Service Center. See Also ½ Chapter 12, Maintenance, has a list of Acterna service centers worldwide. System Information You can view the system information for your unit by selecting the Info icon from the Navigator’s Files and Configure tab.
Description and Basic Operation: Printing Measurements and Files PRINTING MEASUREMENTS AND FILES This section describes the procedures for printing screens or files from your field unit. Before printing, be sure the printer is properly attached. NOTE: Interface the SDA-5000 to a PC with an SDA-toPC cable, P/N 1217-50-0158. The SDA-to-SDA interface cable is P/N 1217-50-0149. The SDA-to-Printer interface cable is P/N 1217-50-0159. These three cables are different.
Description and Basic Operation: Printing Measurements and Files 2 34
Chapter 3 Channel Plans INTRODUCTION Using a channel plan, the SDA field unit memorizes the frequencies of active channels on your system. NOTE: Separate channel plans are required for: • general measurements (tilt, level, and so on) • reverse sweep • loopback sweep Changing the channel plan on the field unit has no effect on the sweep. The headend unit’s channel plan is used by default.
Channel Plans: Channel Plan Configuration CHANNEL PLAN CONFIGURATION To begin, turn the power on and go to the CONFIGURE menu, either by pressing the Nav key, selecting the Files & Configure tab, and then the Config icon, or by pressing the green Function key and then 3 ghi. Depending on your unit’s options, the CONFIGURE menu includes up to six items (see Fig. 3-1). Use the arrow keys to select the CHANNEL PLAN item and then press any soft key.
Channel Plans: Channel Plan Configuration 3 Fig. 3-1 The CONFIGURE Menu Fig. 3-2 The CHANNEL PLAN Menu Options NOTE: If your SDA instrument does not have the QAM option (OPT4), you will not see the Edit Digital Limits. This menu item applies only to QAM signals.
Channel Plans: Setting Channel Plan Parameters SETTING CHANNEL PLAN PARAMETERS To set the channel plan parameters, follow the prompts in the Edit Box and the directions in the following sections. NOTE: The Return soft key in the upper left moves the menu back one screen. Press the soft key next to the Edit Box at the lower right to enter each Channel Plan submenu. 3 Select Channel Plan Selecting the top item, Select Channel Plan, takes you to the screen shown in Fig. 3-3.
Channel Plans: Setting Channel Plan Parameters 1. Scroll through the list to the plan you want to view, then press the Load soft key. 2. Press the Info soft key at the upper right of the display to view the CHANNEL PLAN INFO screen (see Fig. 3-4). This is a view-only screen, which displays main features of the plan specified in the top line. 3 Fig. 3-4 Channel Plan Info 3. Press the Delete soft key to delete a plan. To confirm that you do want to delete the selected plan, press the OK soft key.
Channel Plans: Setting Channel Plan Parameters See Also ½ For more information about these signal types, see the Glossary at the end of this manual. Channel Tuning Sequence At the CHANNEL PLAN menu (Fig. 3.2), select Channel Tuning Sequence and press the Enter key. The up and down diamond keys toggle between Numeric Order and Frequency Order. Select the item desired, press the Enter key again, then use the up or down diamond keys to scroll to the next parameter.
Channel Plans: Setting Channel Plan Parameters 3 Fig. 3-5 The BUILD PLAN STEP 1 Screen 2. The screen prompts you to name the plan. Use the alphanumeric keys and the diamond keys to make your entry, then press the OK soft key to accept it. The screen warns you if there is already a plan with that name entered in the unit. After you enter a name for the plan, the BUILD PLAN STEP 2 screen appears (see Fig. 3-6).
Channel Plans: Setting Channel Plan Parameters 3 Fig. 3-6 The BUILD PLAN STEP 2 Screen 3. At the STEP 2 screen, use the up and down diamond keys to select a base channel plan to use for building the new plan. Press the OK soft key to accept your selection. The screen shown in Fig. 3-7, BUILD PLAN STEP 3, is displayed. Fig. 3-7 The BUILD PLAN STEP 3 Screen 4. At the STEP 3 screen, enter the upper frequency at which to stop searching for channels.
Channel Plans: Setting Channel Plan Parameters down diamond keys to set the frequency, press the Enter key, then press the OK soft key. As the plan starts, you’ll see the basic plan information and the channels being programmed into the plan. CAUTION ! You must press the Enter key to register this frequency as the upper limit. When it’s building the channel plan, the SDA sequences through all channels in the selected base plan up to the Stop Frequency you entered.
Channel Plans: Setting Channel Plan Parameters 3 Fig. 3-8 The EDIT CHANNEL PLAN Screen The eight columns of this screen display the following information about each channel in the plan, left to right: Enabled; Type; Channel; Label; Frequency; Sweep; Tilt; Scrambled NOTE: A check mark in the left margin means that the channel is enabled; SWP, TLT, and SCR channels have asterisks to indicate that status.
Channel Plans: Setting Channel Plan Parameters Use the left and right diamond keys, or the two arrow icons at the upper right corner, to scroll through the list of channels. 3 Fig. 3-9 The EDIT CHANNEL Screen NOTE: If you want to configure a digital carrier in your channel plan, follow the instructions in the section “Configuring a Digital Carrier” at the end of this section. 3. Select the parameter you want to change.
Channel Plans: Setting Channel Plan Parameters Editable Parameters • Enabled: This enables the instrument to monitor the channel. Select Yes or No. If the channel is not enabled it will not be included in any measurement mode. At least one channel must be enabled. • Type: When you select Type, the program offers six choices in the Edit Box. Press the Enter soft key to highlight choices, and use the up and down diamond keys to make the choice.
Channel Plans: Setting Channel Plan Parameters Table 3-1 Carrier Types and Parameters Digital Carrier (DIGI) QAM Digital Stream (QAM) Video + Dual Audio Channels (DUAL) Single Carrier (SNGL) Video Channel (TV) Sweep Insertion Point (SWP) Enabled ✔ ✔ ✔ ✔ ✔ ✔ Type ✔ ✔ ✔ ✔ ✔ ✔ Frequency (MHz) ✔ ✔ ✔ ✔ ✔ ✔ Channel Number ✔ ✔ ✔ ✔ ✔ Label ✔ ✔ ✔ ✔ ✔ Sweep Channel ✔ ✔ ✔ ✔ ✔ Measurement Bandwidth (MHz) ✔ ✔ ✔ ✔ Noise Offset (MHz) ✔ ✔ ✔ ✔ Tilt Channel ✔ ✔ ✔ Sc
Channel Plans: Setting Channel Plan Parameters • Channel Number: This is the channel number of the carrier. Change the channel number by pressing the Enter soft key and using the numeric keypad or the up and down diamond keys. Press the Enter soft key to save the entry. • Label: You can create a distinctive label of up to four characters to attach to the channel’s number. The label associates the channel’s number to programming. Use the Enter soft key, the keypad or the up and down diamond keys.
Channel Plans: Setting Channel Plan Parameters TIP: To increase sweep speeds, a stable audio carrier can be used as a sweep point. Sweeping and measuring a scrambled channel is slower than an unscrambled channel. Add a “SINGLE” type channel at the frequency of the audio carrier and enable this channel for sweep. For a scrambled channel, a diamond appears in the LCD title bar to the left of the channel-type indicator on most screens.
Channel Plans: Setting Channel Plan Parameters the digital channel’s bandwidth, and changes the Measurement BW setting appropriately. If you change from a DIGI or QAM channel to a TV type, the units also adjusts these settings for you. 3 1. From the EDIT CHANNEL PLAN screen (Fig. 3-8), select the channel that you are going to configure as digital, then press the Edit Channel soft key or the Enter keypad key. 2. Highlight the Type item from the list of parameters and press Enter. 3.
Channel Plans: Setting Channel Plan Parameters selecting the unit’s default setting for Inverted Spectrum, which is simply “Yes” or “No”. • For example, when you select the NCTA channel plan, the SDA defaults to Annex B and defaults to “No” regarding Inverted Spectrum because the occurrence of spectrum inversion is not anticipated. If spectrum inversion does occur, however, the setting can be edited to “Yes” on the Edit Channel screen.
Channel Plans: Setting Channel Plan Parameters 4. Press the down diamond key to highlight Standard and press Enter to edit the current selection. Use the down diamond key to select the appropriate Signal Standard and press Enter. 3 Fig. 3-11 EDIT CHANNEL Menu Screen (Inverted Spectrum) 5.
Channel Plans: Setting Channel Plan Parameters • When copying channel plans from unit to unit: • If both units have the current firmware, all of the channel plan information, including Inverted Spectrum, is maintained. • If the unit sending the channel plan is older than SDA v2.5 (no Inverted Spectrum option), the Inverted Spectrum setting for all QAM channels will be defaulted to “No”. • If the unit receiving the channel plan is older than SDA v2.5 and the sending unit is SDA v2.
Channel Plans: Setting Channel Plan Parameters 1. Select Specify Auto Measurements from the CHANNEL PLAN menu and press the Continue soft key. The screen shown in Fig. 3-12, AUTO MEASUREMENTS, appears. 3 Fig. 3-12 The Auto Measurements Screen 2. Use the up and down diamond keys to scroll through the listed channels. 3. Use the bottom right icon’s soft key to program all three measurements for a channel, or use the C/N, Hum, and MOD soft keys separately.
Channel Plans: Setting Channel Plan Parameters CAUTION ! Units cannot be changed after the Auto Test has been completed! Edit Limits Use the Edit Limits option of the CHANNEL PLAN menu to establish standards to be incorporated into an Auto Test. As the Auto Test measurements are running, the program compares measured values to the limits you set for Video Level, Level Delta values, Digital Level, and Max 24hour Level deviation. 3 1. From the CHANNEL PLAN menu shown in Fig.
Channel Plans: Setting Channel Plan Parameters NOTE: You can use the Factory icon soft key at the upper right of the screen to set FCC (US) recommended default values automatically. NOTE: You cannot use the Factory icon to set FCC recommended values when you’re setting Digital Limits. Edit Digital Limits The Edit Digital Limits option on the CHANNEL PLAN menu appears only if your SDA unit is equipped with the QAM option (OPT4).
Channel Plans: Setting Channel Plan Parameters 2. Use the up and down diamond keys to select the limit to be edited. 3. Press the Enter soft key to begin, then use the numeric keypad or the up and down diamond keys to make the entry. When you have made the adjustment, press the Enter soft key again to save the setting and update the display. NOTE: You can use the Factory icon soft key at the upper right of the screen to set all measurements in this screen to the factory recommended default values.
Channel Plans: Setting Channel Plan Parameters 3 58
Chapter 4 Field Sweeping with the SDA-5000 INTRODUCTION This chapter explains the SDA field units’ sweep function. You’ll first be introduced to test point compensation. Next you learn how to configure the field unit to compensate for test point losses and how to calculate those losses. Configuring your receiver for sweep is covered next, after which you learn about connecting the SDA-5000 to test points and how to perform forward and reverse sweeps in the field.
Field Sweeping with the SDA-5000: Test Point Compensation order to perform tests without cutting off service, it is necessary to use test points. Test points are ports that tap off enough signal for monitoring, but leave most of the signal in the system where it is needed. Typical test points have 20-30dB of loss between the signal being measured and the port output. Additionally, it is sometimes necessary to inject or read signals in locations other than the exact point of interest.
Field Sweeping with the SDA-5000: Test Point Compensation Use the top right-hand soft key to toggle between forward and reverse test point displays. Use the top left-hand soft key to return to the previous screen. Use the bottom right-hand soft key to enter the current value from the Edit Box into the test point loss table. 2. The forward test point display has two entries: • The top item (EXTERNAL) is to allow for external pads, coupling networks, or any amplifiers you might use.
Field Sweeping with the SDA-5000: Test Point Compensation Press this soft key to call up the TESTPOINT INFO screen shown in Fig. 4-4. This screen provides information for telemetry and sweep about transmitted output levels, total losses, and actual and desired levels and the delta between them. 4. To accurately calculate reverse test point loss, it’s helpful to have a block diagram of the amplifier to be adjusted.
Field Sweeping with the SDA-5000: Test Point Compensation As an example, consider the amplifier shown in Fig. 4-3: Test Point 20dB PAD H L PAD PAD 3.0dB PAD PAD EQ INPUT OUTPUT 0.5dB H L H L 0.5dB Test Point 20dB OUTPUT 3.5dB EQ PAD 4 Fig. 4-3 Test Point Compensation Values Measured at the test points available at the output of the amplifier, the forward test point loss is 20dB. If you’re balancing constant inputs to the hybrid, the reverse test point loss is 20dB for the test point, plus 1.
Field Sweeping with the SDA-5000: Sweep Receiver Configuration Fig. 4-4 Telemetry and Sweep Generation and Injection Levels 4 The sweep injection level is a nominal value that is not corrected for transmitter calibration because more than one frequency is used for the pulses. For this reason, it is displayed only to the nearest 2dB. When test point compensation changes, the output level of the transmitter changes automatically to keep the system level of the injected pulses the same.
Field Sweeping with the SDA-5000: Sweep Receiver Configuration COMPATIBLE), Loopback, or Sweepless sweep modes. The number of options available to you changes depending on which sweep mode you select. Table 4-1, “Sweep Options,” lists your choices. he Edit Box is sed for data ntry and mode nd option election 4 Fig.
Field Sweeping with the SDA-5000: Sweep Receiver Configuration Table 4-1 Sweep Options 4 Stealth Stealth (SDA Compatible) Transmit (OPT2) Transmit (SDA Compatible) (OPT2) Loopback (OPT2) Sweepless Sweep Mode Sweep Mode Sweep Mode Sweep Mode Sweep Mode Sweep Mode Sweep Limit Variable Sweep Limit Variable Forward Telemetry Freq Forward Telemetry Freq Show Horizontal Markers Sweep Limit Variable Show Horizontal Markers Show Horizontal Markers Forward Sweep Insertion Level Forward Sweep
Field Sweeping with the SDA-5000: Sweep Receiver Configuration SWEEP Menu Options • Sweep Mode: Use the up and down diamond keys to select Stealth, Stealth (SDA COMPATIBLE), Transmit, Transmit (SDA COMPATIBLE), Loopback, or Sweepless. Table 4-1 lists the range of choices in each mode for each of the SDA options. • Sweep Limit Variable: The Sweep Limit Variable is x in the response flatness expression (n/10 + x) used during sweep measurements to compare actual system response to the formula.
Field Sweeping with the SDA-5000: Sweep Receiver Configuration reverse sweep and reverse noise features. This will speed up the SDA-5500’s forward sweep. Also, be sure the telemetry frequencies of the headend units are different. • Forward Sweep Insertion Level (Transmit and SDA Compatible Transmit (OPT2) modes only): This is the level at which sweep insertion points will be inserted; 40 or 50 dBmV is the max. Sweep points should be 14-16 dB below the video reference level.
Field Sweeping with the SDA-5000: Sweep Receiver Configuration Box to set the Reverse Telemetry Level to an appropriate value. When adjusting the Reverse Telemetry Level, set the level to the desired insertion level after loss. The value used includes test point compensation. • Reverse Levels: This option takes you to the REV COMPENSATION screen. From this screen you can set test point losses and the reverse telemetry and reverse sweep insertion levels.
Field Sweeping with the SDA-5000: Considerations for Sweep in the Field stored response during viewing. Use the up and down diamond keys to enable the option. • Include Audio Carriers (Transmit (OPT2) and Sweepless modes only): This selection allows the audio carriers to be excluded, resulting in a faster sweep. Use the up and down diamond keys to include (Yes) or exclude (No) audio carriers. • Sweep Insertion Level (Loopback (OPT2) mode only): This is the level transmitted for each Loopback sweep point.
Field Sweeping with the SDA-5000: Considerations for Sweep in the Field Signal Level Considerations At amplifier test points, the same basic connection and signal level rules apply to the SDA-5000 as apply to the headend unit. Too much signal level on the input of the unit can cause inconsistent sweep readings. The forward telemetry level should be 0dBmV±12dB at the input of the SDA-5000.
Field Sweeping with the SDA-5000: Considerations for Sweep in the Field Wiring and Levels: Reverse Sweep (SDA-5000 OPT1) You can use several connection methods for reverse sweep, depending on system engineering methods and equipment.
Field Sweeping with the SDA-5000: Considerations for Sweep in the Field problem, but an artifact of the type of test point used and impedance mismatches in the network. If the video carriers at the forward test point are above +20dBmV, then use a pad to drop the levels. (Typically this will be the case only when there are direct connections to an amplifier output.) 4 Fig.
Lasers or Distribution Amps PAD PAD Forward Path Lines TP IN OUT SDA-5500 PAD OUT IN Optical Rcvr or Combiners PAD Combining Network Field Sweeping with the SDA-5000: Considerations for Sweep in the Field Reverse Path Lines TP IN OUT SDA-5510 SDA-5000 4 Note: Pads may be omitted if not required for proper levels. Reverse path ALC must be turned off. Fig.
Field Sweeping with the SDA-5000: Considerations for Sweep in the Field Reverse Sweep Operation: • Select Single User for operation with an SDA-5500. • Select Multiple Users for operation with an SDA-5510. Reverse Telemetry Level: This should be calculated by the system engineer and set before you start sweep testing. This value is the system level for telemetry signals after test point connection losses.
Field Sweeping with the SDA-5000: Considerations for Sweep in the Field 4 1. The vertical light bar just above REF at the top of the graph blinks on and off with each trace refresh. 2. The ref level in dB appears in the left top of the graph. 3. The scale in dB/div appears next to the ref level in the middle top of the graph. 4. The upper right corner identifies the kind of sweep: FWD or REV; STEALTH, SDA STEALTH, or SWEEPLESS. 5.
Field Sweeping with the SDA-5000: Considerations for Sweep in the Field 1 2 3 4 5 6 10 8 9 12 11 13 7 Fig. 4-10 The SWEEP Screen NOTE: Most of the displays in this section use these same icons and submenus. The text explains how to use the new ones as they appear. Appendix C contains a listing of the icons referenced throughout this manual.
Field Sweeping with the SDA-5000: Considerations for Sweep in the Field When the lower Start Frequency icon is highlighted, set the lower frequency limit. Press the Enter key to begin, then use the up or down diamond keys, or the numeric keypad, to enter the frequency, and then press Enter again. NOTE: Entering a value outside the sweep plan made in the SDA-5500 will cause the start or stop frequencies to default to the channel plan start or stop frequency. 4 Fig.
Field Sweeping with the SDA-5000: Considerations for Sweep in the Field Level Screen You can set the reference levels from the screen shown in Fig. 4-12, or you can use the diamond keys. Call up the level screen from the SWEEP screen (Fig. 4-10) by pressing the soft key above the Frequency Submenu icon. Press the soft key next to the Reference Level icon on the right side of the display for manual reference level adjustment.
Field Sweeping with the SDA-5000: Considerations for Sweep in the Field Limit Screen The screen shown in Fig. 4-13 is where you set the value for n in the equation n/10+x, and set the Limit in dB. NOTE: You set the x in n/10+x from the main SWEEP menu’s Sweep Limit Variable option. (See “SWEEP Menu Options” on page 67.) Call up the limit screen from the SWEEP screen (Fig. 4-10) by pressing the top soft key on the right side of the screen.
Field Sweeping with the SDA-5000: Considerations for Sweep in the Field Press the Enable/Disable icon to turn the limit on or off. Notice LIMIT box immediately to the left of the LIMIT icon under the lower right corner of the graph. When you’re done here, use the Limit Submenu icon to return to the main SWEEP screen. NOTE: Notice the Limit box at the lower right of the graph next to the Limit Submenu icon. A check mark means pass, an X means fail. Tilt Screen The Tilt screen (shown in Fig.
Field Sweeping with the SDA-5000: Considerations for Sweep in the Field Tilt compensation is displayed here 4 Fig. 4-14: The SWEEP Tilt Screen Reverse Sweep Operation (SDA-5000 OPT1) Sweeping the reverse path is a little different from sweeping the forward path. Because the system is designed with appropriate spacing for the forward high frequency range, the reverse path might not require amplification at each station. The lower frequencies are not attenuated in cable as much as the higher frequencies.
Field Sweeping with the SDA-5000: Considerations for Sweep in the Field the headend (SDA-5500 and/or SDA-5510) and in the field (SDA-5000). See Also ½ Chapter 14, “SDA-5500/SDA-5510 Sweep Considerations,” goes into more detail about the concept of reverse sweeping. ½ “Reverse Sweep and Balance” in Appendix A provides more information about reverse sweep setup, operation, troubleshooting, and tips & hints (page 318).
Field Sweeping with the SDA-5000: Considerations for Sweep in the Field See Also ½ “Test Point Compensation Configuration” provides an example of test point loss calculation (page 60). CAUTION ! Setting the correct reverse sweep signal level is critical to achieving accurate results without creating interference for reverse path services. In general, both the reverse telemetry and reverse sweep levels can be set to the same value and system specs.
Field Sweeping with the SDA-5000: Considerations for Sweep in the Field This icon shows whether the unit is Sweep or Noise enabled Sweep direction is indicated here 4 Fig. 4-15 Reverse SWEEP Screen Notice the small icon at the upper right corner of the graph. This icon shows whether the unit is Sweep or Noise enabled. (Fig. 4-18 shows a Noise enabled screen.) Press the Sweep Enable soft key to display the reverse sweep trace. Press the Noise Enable soft key to display the noise trace.
Field Sweeping with the SDA-5000: Considerations for Sweep in the Field Reverse Frequency Screen From the Frequency screen you can set the start and stop reverse frequencies (see Fig. 4-16). 4 Fig. 4-16 The Reverse SWEEP Frequency Screen Call up the frequency screen from the SWEEP screen by pressing the soft key in the lower left corner. Use the Start Frequency icon to set the lower frequency limit. Set the value with either the numeric keypad or the up and down diamond keys.
Field Sweeping with the SDA-5000: Considerations for Sweep in the Field Call up the level screen from the SWEEP screen (Fig. 4-10) by pressing the soft key above the Frequency Submenu icon. Press the soft key next to the Reference Level icon on the right side of the display for manual reference level adjustment. Use the up or down diamond keys, or the numeric keypad, to enter the level, and then press Enter. Note the changes in the graph as you adjust the values. 4 Fig.
Field Sweeping with the SDA-5000: Considerations for Sweep in the Field The display will change to a noise response indicating the noise level at the marker frequencies. See Also ½ For more information, see “The Noise Mode” in Appendix A (page 331). Press the Noise Enable soft key to display the noise trace. Press the Sweep Enable soft key to display the reverse sweep trace. Use the Frequency Submenu icon to call up the Noise Frequency screen. Use the Level Submenu icon to call up the Noise Level screen.
Field Sweeping with the SDA-5000: Considerations for Sweep in the Field the level, and then press Enter. Note the changes in the graph as you adjust the values. 4 Fig. 4-19 The Reverse SWEEP Noise Level Screen Press the Autoscale soft key to auto reference the level. This automatically sets the scale to a convenient level for optimum viewing in the center of the screen. Press the Scale soft key to adjust the graph’s scaling.
Field Sweeping with the SDA-5000: Considerations for Sweep in the Field and down diamond keys. Save your setting by pressing the Enter key. 4 Fig. 4-20 The Reverse SWEEP Noise Frequency Screen You can return to values previously set with the icon in the lower right of the display. When you’re finished, press the soft key next to the Frequency Submenu icon on the left side of the display to return to the SWEEP menu.
Field Sweeping with the SDA-5000: Considerations for Sweep in the Field Use the LO soft key to set the low frequency for tilt/gain to the current marker. Use the HI soft key to set the high frequency for tilt/gain to the current marker. 4 Fig. 4-21 The REV ALIGNMENT Main Screen The upper soft icon on the right side of the display does not have an assigned function in this screen. Use the Level Submenu icon to enter the Reverse Amplifier Alignment Level screen.
Field Sweeping with the SDA-5000: Sweepless Sweep available (1, 2, 5, and 10 dB/div). Notice what happens to the display as you change the scale factor. Note the changes to the display as you change the values. Press the Level Submenu icon to return to the main REV ALIGNMENT screen. 4 ach H.E. value s the level eceived in the eadend at the ndicated requency (LO r HI). Each IN value represents the sweep and telemetry levels inserted after test point losses. Fig.
Field Sweeping with the SDA-5000: Loopback Sweep (OPT2) mode. Sweepless sweep must always be performed using references. After several traces have been acquired, press the Function and 6 pqr keys to store a reference. This will now be used as a sample of the ‘perfect’ system levels against which other test points will be compared. See Also ½ “Sweep References” in Chapter 11 has more information about storing sweep references (page 201). When you reach another test point, press Sweep again.
Field Sweeping with the SDA-5000: Loopback Sweep (OPT2) Fig. 4-23 The Loopback SWEEP Screen 4 The title of the current Loopback sweep reference is at the bottom right of the screen. If no sweep reference is selected, this will read NONE. If a previously stored reference is selected, all levels are displayed in dB. When the reference is NONE, levels are displayed in the units selected at the MEASUREMENT configuration screen during Global setup (see “Measurements Configuration” in Chapter 2, page 25).
Chapter 5 Reverse Path Troubleshooting INTRODUCTION This chapter outlines some reverse path troubleshooting problems and discusses techniques you can employ with the SDA-5000. For future application notes outlining more techniques, please see your local Acterna CATV sales representative. Table 5-1 offers some ideas on the best application of the SDA-5000’s capabilities to help you troubleshoot reverse path problems.
Reverse Path Troubleshooting: Problems in Advanced Services PROBLEMS IN ADVANCED SERVICES For two-way systems, ingress and noise are far greater problems in the reverse path than they are in the forward path. The reasons— accumulation of noise, many diverse ingress sources, random noise, physical plant problems, and CSO intermodulation—are fairly common: • Accumulation of Noise: Accumulation of noise means that problems compound far more quickly than in the forward path.
Reverse Path Troubleshooting: Problems in Advanced Services F ib e r Fig. 5-2 Customers Affected by a Return Path Ingress Source To see how this affects noise floors, think about how much of the network can inject noise that affects a given customer. For forward path signals, the only potential problem areas are the direct path from the customer’s home to the headend. For reverse path signals, problems can come from anywhere in the area served by one headend receiver.
Reverse Path Troubleshooting: Problems in Advanced Services • CSO (Composite Second Order) Intermodulation: A clustering of second-order beats in the video bandwidth can cause distortion in the system. Problems in Troubleshooting the Reverse Path Troubleshooting noise in the reverse path is more complex than it is in the forward path, and can require far more time and energy to correct, as well as being much more frustrating.
Reverse Path Troubleshooting: Problems in Advanced Services • Compare the headend noise spectrum to the local spectrum. This allows you to determine whether a problem you see in the field matches the headend problem. • Use Dwell Time in spectrum analysis. The more time a meter spends looking for ingress, the more likely it is to catch a random/transient problem. • Fast scanning gets data in real time, and makes diagnosis much faster.
Reverse Path Troubleshooting: CPD (Common Path Distortion) Analysis CPD (COMMON PATH DISTORTION) ANALYSIS CPD (Common Path Distortion) is a form of intermodulation distortion that occurs as the RF spectrum is mixed as it passes through a non-linear junction. This phenomenon results in beat products that appear in the reverse spectrum and impair communication.
Reverse Path Troubleshooting: CPD (Common Path Distortion) Analysis Technicians need to be able to associate seemingly “unconnected” symptoms. For example, someone notices a minor amount of hum in the picture of a customer; two blocks away error rates start going up on a data modem or DMX box. Somewhere in the area you find a connector cracked at the housing entry which has allowed moisture entry and oxidation to occur. Note that this can and does happen to F connectors in homes or institutions.
Reverse Path Troubleshooting: Evaluating TDMA Return Path Signals likelihood of this occurring, the transmitter should be configured such that the video signal input level is at approximately 0 dBmV. In the event that instrument related intermodulation occurs, the reverse channel plan may be set up such that the frequencies at which the intermod products appear are not included. Alternatively, an SDA-5510 can be used.
Reverse Path Troubleshooting: Evaluating TDMA Return Path Signals quadrature modulation are used to increase the available modulation bandwidth so that a TDMA cell-phone sends the same information in onethird the time of an AMPS cell-phone. Through time-interleaving, three cellphones now occupy the same frequency bandwidth that one occupied just a few years ago. Another area of rapid growth using TDMA is CATV reverse path. Today’s CATV system includes many different signal and modulation types.
Reverse Path Troubleshooting: Evaluating TDMA Return Path Signals Troubleshooting TDMA Current reverse path troubleshooting strategies are not capable of detecting problems inside of a TDMA modem’s frequency allocation. While checking the level at each frequency is a good start for characterizing the reverse path performance, a spectrum graph only looks at each frequency for a small percentage of the total time.
Reverse Path Troubleshooting: Evaluating TDMA Return Path Signals viewing TDMA signals. This will allow the capture of the TDMA events for analysis. Zero Span mode shows a number of parameters from a TDMA signal, including the power of the carrier, the noise floor, and interference. Fig. 5-5 shows the Zero Span display of a TDMA signal with an ideal noise floor. The “D” marker shows the power of the TDMA desired signal. The “U” marker shows the power of the undesired or noise floor.
Reverse Path Troubleshooting: Evaluating TDMA Return Path Signals Fig. 5-6 Signal with High Noise Floor in Zero Span 5 Intermittent ingress along with the TDMA signal is a pesky problem when troubleshooting return path issues. This is a hit-or-miss game. With a spectrum graph you are completely at the mercy of luck. As you can see, when there is a signal with intermittent ingress (see Fig. 5-7), there are additional pulses. The “U” marker in this screen clearly shows a peak “D/U” of 30 dB.
Reverse Path Troubleshooting: Evaluating TDMA Return Path Signals Fig. 5-7 Time Domain Signal with Intermittent Ingress in Zero Span Looking at TDMA signals can be confusing. Implementing return path modem is necessary to keep current customers and attract new revenue. Viewing the reverse path in a spectrum graph can give you a good idea of overall system health. To manage TDMA signals cost-effectively, you need a time domain view.
Reverse Path Troubleshooting: Evaluating TDMA Return Path Signals References 5 108 1. Cable Television Laboratories, “Data-Over-Cable Service Interface Specification”, SP-RFI-102-971008, Interim Specification, 1997. 2. Cable Television Laboratories, “Characterization of Upstream Transient Impairments on Cable Television Systems”, February 12, 1997. 3. Kevin J. Oliver, “Preventing Ingress in the Return Path”, CED Magazine, Oct. 1997. 4.
Chapter 6 Measuring System Performance INTRODUCTION This chapter explains how to evaluate system performance by measuring key parameters, both as part of routine monitoring and corrective maintenance. Operations covered include performing Level, Tilt, Scan, Carrier-to-Noise ratio (C/N), Hum, Modulation-Demodulation, Composite Second Order (CSO) and Composite Triple Beat (CTB) measurements.
Measuring System Performance: Measuring Signal Levels MEASURING SIGNAL LEVELS You measure signal levels in the Level, Tilt, and Scan modes. In Level and Scan, the process measures the difference between video and audio for a channel and displays the difference in dB. In Tilt mode, the difference, or tilt, refers to the difference in dB between the upper and lower pilot channels.
Measuring System Performance: Measuring Signal Levels 1 2 5 3 4 6 Fig. 6-1 The LEVEL Measurement Mode Screen The following information is displayed in the Level measurement mode screen (numbers correspond to callouts in Fig. 6-1): 1. Channel number or frequency 2. Channel label, video carrier frequency, and level dBmV (or dBuV— this is a configuration parameter) 3. Audio carrier frequency in MHz and level 4. Delta between audio and video levels (dB) 5.
Measuring System Performance: Measuring Signal Levels Fig. 6-2 LEVEL Mode Display, Specific Frequency Only Note that dual audio carrier channels display two audio graphs. Scrambled channels have the same appearance as non-scrambled channels (but with a different icon—see page 46 for a list of channel type icons). You must designate scrambled channels in the EDIT CHANNEL PLAN submenu of the CHANNEL PLAN menu.
Measuring System Performance: Measuring Signal Levels Tilt Compensation The Tilt compensation feature allows you to enter the cable loss for a particular section of coax and then, using the scan display, you can adjust the gain of the amplifier to compensate for this loss. You can turn Tilt compensation on or off in the TILT submenu. The SDA-5000 enables you to designate up to nine Tilt channels. See Also ½ "Edit Channel Plan" in Chapter 3 explains how to designate Tilt channels (page 43).
Measuring System Performance: Measuring Signal Levels The Tilt adjustment uses amplifier gain to compensate for the attenuation of signals moving through the cable. Higher frequencies are attenuated more than lower frequencies. This accounts for the slope of the line in Fig. 6-3. Tilt mode simplifies the actual balancing by displaying a bar graph with a representation of up to nine video carrier levels.
Measuring System Performance: Measuring Signal Levels specified levels for signals at the high and low end of the spectrum, used for Automatic Gain Control (AGC) or Automatic Slope Control (ASC), respectively. In the amplifier balancing process, these signals are measured and adjusted to specification. In practice, before adjusting compensation of the amp, first check that there are no problems in the system requiring repair.
Measuring System Performance: Measuring Signal Levels Scan Rates Two scan rates can be selected in Scan mode, normal and fast. Select Scan Rate in the MEASUREMENT menu (from the Global Configuration menu). The fast scan feature allows for rapid scan displays, at reduced accuracy (as much as 2 dB on scrambled channels.) Normal scan rate is slower, but is much more accurate. When fast is selected, a speeding bullet icon appears in the upper left hand corner of the SCAN screen.
Measuring System Performance: Measuring Signal Levels • If Tilt compensation is on, you will see a small version of the tilt icon at in the top center of the screen, and at the bottom-center of the screen, the Tilt compensation value. • Immediately below the graph, numerical values are displayed.
Measuring System Performance: Measuring Signal Levels Pressing this resets the start and stop frequencies to full span. Press this to zoom to values previously set. TILT Submenu Press to bring up the TILT submenu, then to return to the main SCAN screen Press to turn Tilt compensation on or off. LIMIT Submenu Press to bring up the LIMIT submenu, then to return to the main SCAN screen. Press to turn Limit on or off.
Measuring System Performance: Carrier-to-Noise Measurements The Limit feature allows for comparison of the current scan measurement with the FCC or other conformance/test limits defined during setup and configuration. There are two parts to this feature: • When an out-of-tolerance condition exists, a set of annunciators will appear below the graph.
Measuring System Performance: Carrier-to-Noise Measurements then averages the values. This value is then corrected for the selected bandwidth, and the C/N ratio is computed. CAUTION ! If you select C/N mode before a carrier is available at the input of the SDA-5000, the readings will be wrong. If this occurs, change to another mode or channel and then return to the channel you want. Also, be sure you wait long enough for the C/N calibration to finish to be sure you have accurate readings.
Measuring System Performance: Modem Carrier-to-Noise Measurements Enter the BANDWIDTH submenu; return to C/N main menu. Enable or disable 13 dB amplifier Enable or disable 50 MHz low-pass filter (icon shows disabled) Fig. 6-6 Carrier-to-Noise Measurement 6 NOTE: The US FCC specification for C/N measurements is a bandwidth of 4.000 MHz. CATV organizations outside of the United States may have different requirements.
Measuring System Performance: Modem Carrier-to-Noise Measurements as trigger level threshold, sweep time, measurement bandwidth, video bandwidth, and resolution bandwidth. You must also be proficient at RF signal evaluation in the time-domain mode (versus the standard frequency domain mode). To overcome the confusing test equipment set-up process, Acterna has introduced a new instrument feature that allows technicians at all skill levels to perform accurate return-path cable modem C/N measurements.
Measuring System Performance: Modem Carrier-to-Noise Measurements Bandwidth. If any of these parameters change, the measurement cycle will start over from the beginning, so it is not necessary to force the unit to restart its measurement manually. To keep the display free from clutter, not all measured values are displayed: Only the average power of each signal detected is displayed.
Measuring System Performance: Hum Measurements marker so that it is more convenient for the user to select the desired (example: worst case) noise floor level. The reset soft key will cause the measurement to recycle. This action is desired if the same input has been monitored for a long period of time, and the user wants to monitor the input to catch ingress.
Measuring System Performance: Hum Measurements Fig. 6-8 The HUM Measurement Screen A proprietary DSP technique enables hum measurements, in-service, on modulated carriers (non-scrambled channels). The SDA-5000 can measure the 1 Hz hum component. To activate this feature, set the fundamental hum frequency in the MEASUREMENT screen to 1 Hz. The filter options on the Hum display will then become 1 Hz, <50 Hz, and <1 kHz.
Measuring System Performance: Modulation Measurements MODULATION MEASUREMENTS The MODULATION screen allows you to monitor the video depth of modulation in graphical and precise numerical format. The software shows a marker at the optimal modulation level (NTSC 87.5%, PAL 90%) to assist you in making adjustments. You can also listen to the audio modulation of the tuned channel or frequency. Fig.
Measuring System Performance: Modulation Measurements Fig. 6-10 The MODULATION Audio Menu Use icons from the Audio screen as follows: Enter the Amplifier/Low-Pass submenu and return to the main Audio sub-menu when appropriate.
Measuring System Performance: CSO/CBT Measurements CSO/CBT MEASUREMENTS CSO (Composite Second Order) is a clustering of second order beats at certain frequencies in the spectrum. These beats cause interference to picture quality when they fall within the video bandwidth. CTB (Composite Triple Beat) is a clustering of third order distortion products usually around the video carrier frequency.
Measuring System Performance: CSO/CBT Measurements After a brief interval, the screen shown in Fig. 6-12 appears, showing the measurement traces. Fig. 6-12 CSO/CTB, Carrier OFF The light trace represents the carrier prior to its being turned off. The dark trace represents the distortion products. The measurement value is computed by the ratio of the peak level of the video carrier to the peak of the distortion products of the second and third order beats. The worst case CSO value is highlighted.
Measuring System Performance: CSO/CBT Measurements Fig. 6-13 CSO/CTB Offsets Using the up and down diamond keys, select the CSO Offset number to change. Use the numeric entry keys or the up and down diamond keys to enter a new CSO Offset value. Upon exiting the CSO/CTB measurement, the SDA-5000 prompts you to turn the carrier back on.
Chapter 7 Spectrum Analyzer Mode INTRODUCTION In the Spectrum Analyzer mode, the instrument displays all or part of the CATV system spectrum, with variable spans from 3 to 50 MHz. A dynamic range better than 60 dB over the six vertical subdivisions of the display graph allows for comprehensive troubleshooting utility. Spectrum measurement mode reveals ingress spikes as brief as 5 µs. The Zero-Span mode of the spectrum analyzer displays a single frequency over time.
Spectrum Analyzer Mode: Spectrum Mode Operation Fig. 7-1 The SPECTRUM Mode Main Screen Below are the primary functions of the soft keys in the SPECTRUM screen. Notice that the Ref Level in dBmV and Scale Factor in dB/div are always displayed at the top of the graph. The center frequency is displayed below the title bar in the top right corner. The span is displayed in the status bar above the graph. Press the Amplifier/Low Pass Filter soft key to enter the AMPLIFIER/LOW PASS FILTER screen.
Spectrum Analyzer Mode: Spectrum Mode Operation This mode guides the user through the measurement of Composite Second Order and Composite Triple Beat products. Fig. 7-2 shows the instrument’s capability as spectrum analyzer. The full range is 5 MHz to 1,000 MHz, with a span of ± 1.5, 2.5, 5, 10, or 25 MHz around the specified center frequency. For use along the return path, with low pass filters engaged, the spectrum is reduced to 5 MHz to 50 MHz.
Spectrum Analyzer Mode: Spectrum Mode Operation LEVEL Submenu Press this to enter the LEVEL submenu, then to return to the main menu. Use the Level soft key to adjust the vertical parameters of the graph. These parameters include the following: The reference level is located at the top of the screen. You can adjust it using the up and down diamond keys, or by entering a numeric value with the keypad and then pressing the Enter key.
Spectrum Analyzer Mode: Spectrum Mode Operation Selects trace Dwell-Time (the time that the instrument looks for signal on each frequency). Longer dwell-time enables you to check for transient ingress. Use either the numeric keypad, the Enter key, or the up and down diamond keys to adjust this value from 64 µSec to 25 mSec. Scan time will increase to a maximum of approximately seven seconds when dwell-time is set to 25 mSec.
Spectrum Analyzer Mode: Spectrum Mode Operation Fig. 7-3 The Spectrum Analyzer ZERO SPAN Screen ZERO SPAN Submenu Press this to enter the ZERO SPAN submenu. In Zero Span mode, the instrument displays the trace of one discrete frequency over time. Sweep time is on the x-axis, and amplitude (dBmV) is on the y-axis. You can change the sweep time for either a closer or a wider look, as necessary. Zero Span incorporates a large menu of useful features.
Spectrum Analyzer Mode: Spectrum Mode Operation Press to enter the TIMEBASE submenu, then to return to ZERO SPAN main menu. Use the up and down diamond keys to scroll through sweep times offered in the Edit Box, and to turn the auto sweep trigger on or off. Press to enter the LEVEL submenu, then again to return to the ZERO SPAN screen. Press to change the active marker between Desired (Signal) and Undesired (Noise).
Spectrum Analyzer Mode: Spectrum Mode Operation TIMEBASE Submenu Press the Timebase soft key to enter the TIMEBASE submenu. Press this soft key to set sweep time. Increments are entered using the up and down diamond keys. Options include • 20, 10, 05, 02, 01 seconds • 500, 200, 100, 50, 20, 05, 20, 10, 02, 01 milliseconds • 500, 200, 100 microseconds Press to turn sweep trigger on or off using the up and down diamond keys. With the trigger off you get a continuous update.
Spectrum Analyzer Mode: Spectrum Mode Operation BANDWIDTH Submenu Press to set Resolution Bandwidth at values of 30 kHz, 280 kHz, or 2 MHz. A value of 280 kHz is used as the nominal value. When carrier spacing is very narrow or very wide, 30 kHz or 2 MHz, respectively, may be used. Press to set the Video Bandwidth at values of Auto, 100 kHz, 10 kHz, or 100 Hz. Auto should be used to prevent aliasing. You might want to change to a low value when looking at carrier power.
Spectrum Analyzer Mode: Spectrum Mode Operation 7 140
Chapter 8 PathTrak Field View (OPT3) INTRODUCTION PathTrak mode operation is available only if your unit has OPT3, Field View. The PathTrak mode provides increased troubleshooting accuracy by allowing the technician to compare spectrum measurements at the node with the current conditions at the headend. In the PathTrak mode, the SDA5000 field receiver displays all or part of the return path spectrum in the 5MHz to 65MHZ range.
PathTrak Field View (OPT3): PathTrak Mode Operation Fig. 8-1 The PATHTRAK Configuration Screen To get to the PATHTRAK configuration screen, select the PATHTRAK option from the main CONFIGURE menu. • Telemetry Frequency: Select this option from the PATHTRAK configuration screen. A telemetry carrier is used to transmit data from the PathTrak Headend Stealth Modem to the field unit. Set the telemetry frequency between 5 MHz and 1000 MHz by using the numeric keypad and then press the Enter key.
PathTrak Field View (OPT3): PathTrak Mode Operation displays the spectrum in the field, and the Remote trace displays the spectrum taken at the PathTrak System (See Figures 8-2 and 8-3). The SDA-5000 field receiver displays the spectrum of any node that is currently monitored by the PathTrak System and that is selected for broadcast. Local Trace – Field Measurement Remote Trace – PathTrak Measurement Press the Trace soft key to toggle between the Local and Remote trace.
PathTrak Field View (OPT3): PathTrak Mode Operation Fig. 8-3 PathTrak Mode – Remote Trace The following sections describe the functions of the soft keys available in the PathTrak mode. AMPLIFIER/LOW-PASS FILTER Submenu Press this soft key to access the Built-in Amplifier and Low-pass Filter submenu. This option is available in Local trace measurement only. Press again to return to the PATHTRAK main menu.
PathTrak Field View (OPT3): PathTrak Mode Operation When you’re in the Dual Marker mode, this key toggles the cursor between A and B. Select this when you want to compare the amplitude at two different frequencies for either the Local or the Remote trace. This soft key selects the Peak Search function. When selected, the active marker is automatically positioned at the frequency of the highest amplitude in the spectrum graph of the current active trace.
PathTrak Field View (OPT3): PathTrak Mode Operation provide the PathTrak system administrator with the identification (ID) number of the requested node. The ID number is located on the bottom-left of the screen (see Fig. 84). Select the Node Toggle soft key to toggle between the Broadcast Nodes view (See Fig. 8-4) and the All Nodes view (See Fig. 8-5). Fig. 8-4 Broadcast Node View 8 Fig.
PathTrak Field View (OPT3): PathTrak Mode Operation Node Selection NOTE: Only Broadcast nodes can be selected for viewing. Broadcast nodes are indicated by a dot to the left of the node. Highlight the node you want to view and press this soft key. A check mark will appear next to the selected node. Once the desired node is selected for viewing, press the Enter key to go directly to the PathTrak mode.
PathTrak Field View (OPT3): PathTrak Mode Operation 8 148
Chapter 9 Digital Analysis (QAM View OPT4) INTRODUCTION This chapter reviews the features and operation of the SDA digital analysis option (QAM View OPT4). In addition to a Quick-Start overview, four primary operational modes are discussed, including Digital Summary, QAM Ingress, Constellation, and Equalizer. Digital Analysis operation is available only if your SDA is equipped with QAM (Quadrature Amplitude Modulation) View (SDA Option 4).
Digital Analysis (QAM View OPT4): Quick Start QUICK START For experienced users of the Stealth Digital Analyzer, or for users familiar with other types of digital analysis equipment, this section provides a brief overview of the functionality of the SDA’s four digital modes. Use this section to quickly begin analyzing aspects of the digital signal and refer to the sections that follow for a more detailed review of each digital mode.
Digital Analysis (QAM View OPT4): Quick Start Fig. 9-2 Digital Measurement Mode Keys To activate DIGITAL Summary Mode, press the green Function key and then press the C/N Measurement Mode key. To activate EQUALIZER Mode, press the green Function key and then press the Hum Measurement Mode key. To activate CONSTELLATION Mode, press the green Function key and then press the Mod Measurement Mode key. To activate QAM INGRESS Mode, press the green Function key and then press the Spect Measurement Mode key.
Digital Analysis (QAM View OPT4): Quick Start display shows the channel, modulation format, the symbol rate, the carrier offset (in KHz), the equalizer stress. Press this key to view the digital DETAIL display. Press this key to view the QAM Level display. QAM Ingress Mode (Quick Start) QAM INGRESS Mode provides a spectrum view of ingress noise, CSO/CTB, and other coherent (in-band) noise occurring at levels beneath the digital signal. Measurement data is shown on two lines, A and B, below the graph.
Digital Analysis (QAM View OPT4): Digital Summary Mode Press this key to Zoom-In one level on the framed quadrant. Equalizer Mode (Quick Start) The Adaptive Equalizer corrects the effects of reflections in the transmission path. The Equalizer Mode indicates the strength of specific reflections, their location in relation to the test point location, and how hard the equalizer is working to correct them.
Digital Analysis (QAM View OPT4): Digital Summary Mode Features and Definitions DIGITAL Main Screen Features The DIGITAL Main Screen (see Fig. 9-3) displays the: • channel number and modulation format • Modulation Error Ratio (MER) / Error Vector Magnitude (EVM) • Bit Error Rate (BER) before Forward Error Correction (FEC) • Bit Error Rate after Forward Error Correction. This screen also assigns a Pass or Fail value to these measurements in relation to user-defined error limits.
Digital Analysis (QAM View OPT4): Digital Summary Mode of bits in the data transmission. This ratio is expressed in scientific notation, where 1e-3 equals one error in every 1000 bits transmitted. One error in every 1,000,000 bits transmitted is expressed as 1e-6. A more negative exponent value indicates a lower error rate. BER is another good indicator of overall system performance. The SDA has Pass/Fail BER default thresholds of 1e-8 before Forward Error Correction and 1e-9 after Forward Error Correction.
Digital Analysis (QAM View OPT4): Digital Summary Mode Equalizer Stress Equalizer stress is ranked as Low, Medium, or High on the DETAIL Display. The Equalizer Mode provides more specific information about equalizer stress. Carrier Offset The Carrier Offset value shown in the digital DETAIL Display indicates how far off center (in kHz) the digital signal is from the tuned frequency of the SDA.
Digital Analysis (QAM View OPT4): Digital Summary Mode Connect the cable to the digital port on the unit before using any of the four digital modes. If initially unsuccessful, the following error message will appear: “ERROR … Signal Unlocked! Confirm Connection to Dig Port. Retry.” Press this soft key to retry to lock onto the QAM signal. This key will appear in the lower right corner of the screen when lock errors occur, otherwise the key will remain blank.
Digital Analysis (QAM View OPT4): Digital Summary Mode Fig. 9-5 QAM Level Display Press this key to return to Digital Summary Mode. Editing the Modulation Format Press this key to edit the modulation format. Changes to the modulation format should be made only when it is certain that the modulation of the digital signal is not compatible with the current setting. Use the up or down diamond keys to select the alternate modulation format. Edits to the modulation format may be saved to the Channel Plan.
Digital Analysis (QAM View OPT4): Digital Summary Mode Fig. 9-6 Editing the Modulation Format Press this key to save the new modulation format to the channel plan. Press this key to return to the main Digital Summary Mode display. Editing the Symbol Rate Press this key to edit the Symbol Rate. Edits to the default rate should be made only when more accurate data is obtained from equipment specifications or further analysis of the signal.
Digital Analysis (QAM View OPT4): QAM Ingress Mode Fig. 9-7 Editing the Symbol Rate Press this key to save the symbol rate to the channel plan. Press this key to return to the main Digital Summary Mode display. QAM INGRESS MODE QAM INGRESS Mode provides a spectrum view of ingress noise, CSO/CTB, and other coherent noise occurring at levels beneath the digital signal. It allows a view “under the signal” by removing the QAM signal and displaying the remaining spectrum.
Digital Analysis (QAM View OPT4): QAM Ingress Mode • channel number and modulation format • graph reference and scale values • left, center, and right frequencies on the graph • two cursor frequency and level (in relation to the carrier) values • Delta of the two cursor values. This screen also shows the interference level in dBc values for each cursor. This value, called “decibels with respect to the carrier,” indicates the noise power with respect to the signal power.
Digital Analysis (QAM View OPT4): QAM Ingress Mode Fig. 9-8 QAM INGRESS Main Screen The SDA will automatically attempt to lock-on to the QAM signal of the designated channel (or frequency). Lock errors may result from a variety of conditions, including improper unit configuration or cable connection. Connect the cable to the digital port on the unit before using any of the four digital modes.
Digital Analysis (QAM View OPT4): QAM Ingress Mode Measurement data is shown on two lines, A and B, below the graph. These two lines show the readings of the vertical markers on the graph. Press this key to select the active vertical marker. The dotted line is the active marker. The solid line (other marker) does not move. The active marker moves with the left and right diamond keys. Press this key to automatically place the active marker at the frequency with the greatest amplitude.
Digital Analysis (QAM View OPT4): QAM Ingress Mode These three parameters may be edited to allow different views of the QAM ingress signal on the graph. Editing the Reference Level By adjusting the reference level, the signal plot can be vertically centered on the graph to show both the noise floor and the peak of the highest amplitude. Press this key to select the Reference Level edit option (see Fig. 9-9). Use the alphanumeric keypad to define the desired level and press the Enter key.
Digital Analysis (QAM View OPT4): QAM Ingress Mode Fig. 9-10 Editing the QAM Ingress Scale Parameter Press this key to return to the QAM INGRESS Main Screen. Selecting the Maximum Hold Function When this option is selected, the graph compiles successive signal plots to show variances in the signal over time. Press the reset key (shown below) to clear the graph of collected data and restart the Maximum Hold function. Press this key to select the Maximum Hold edit screen (see Fig.
Digital Analysis (QAM View OPT4): Constellation Mode Fig. 9-11 Maximum Hold Function Selected Press this key to return to the QAM INGRESS Main Screen. CONSTELLATION MODE CONSTELLATION Mode shows a picture of the quality of the demodulated digital signal prior to error correction. Identifying a specific constellation pattern on the grid and associating this pattern with a specific type of impairment quickly leads to troubleshooting options that minimize or eliminate the impairment.
Digital Analysis (QAM View OPT4): Constellation Mode Common Impairment Types Figures 9-12 through 9-14 show constellation displays depicting three common impairments – thermal (system) noise, phase noise, and coherent interference. Gain compression and I/Q imbalance (not shown here) are examples of two other impairment types with specific graphic signatures.
Digital Analysis (QAM View OPT4): Constellation Mode Fig. 9-13 Phase Noise Impairment Coherent interference impairments -- such as CTB, CSO, and spurs -cause the dots on the graph to cluster with an empty space in the middle (see Fig. 9-14). Fig.
Digital Analysis (QAM View OPT4): Constellation Mode QAM Modulation and Symbol Rates The SDA analyzes two Quadrature Amplitude Modulation formats, 64 QAM and 256 QAM. The Symbol Rate corresponds to the size and shape (bandwidth) of the digital signal. This rate is expressed in “millions of symbols per second” (Msym/s) and may be edited in the Digital Summary Mode. The default for 64 QAM is 5.057. The default for 256 QAM is 5.360.
Digital Analysis (QAM View OPT4): Constellation Mode CONSTELLATION Main Screen Features From the CONSTELLATION Main Screen (Fig. 9-15) you can • view a graphic depiction of the signal • examine MER and BER data • select closer views of the impairment • edit the modulation format and symbol rates • access the QAM Level display. Fig. 9-15 CONSTELLATION Main Screen The SDA will automatically attempt to lock-on to the QAM signal of the designated channel (or frequency).
Digital Analysis (QAM View OPT4): Constellation Mode Viewing the QAM Level Display Press this key to view the QAM Level display. Fig. 9-16 QAM Level Display Press this key to return to Digital Summary Mode. Editing the Modulation Format or Symbol Rate Press this key to edit the modulation format. Changes to the modulation format should be made only when it is certain that the modulation of the digital signal is not compatible with the current setting.
Digital Analysis (QAM View OPT4): Constellation Mode Use the alphanumeric keypad to define the new symbol rate, and then press the Enter key. Edits to the symbol rate may be saved to the Channel Plan. Using the Zoom Feature Use the Zoom feature to examine the constellation in more detail. In 64 QAM, three grids are available for viewing – 8x8, 4x4, and 2x2 (see Figures 9-17 through 9-19). In 256 QAM, four grids are available for viewing – 16x16, 8x8, 4x4, and 2x2. Press this key to enter the Zoom Submenu.
Digital Analysis (QAM View OPT4): Constellation Mode Fig. 9-17 64 QAM 8x8 Zoom Screen Fig.
Digital Analysis (QAM View OPT4): Equalizer Mode Fig. 9-19 64 QAM 2x2 Zoom Screen EQUALIZER MODE The Adaptive Equalizer corrects the effects of reflections and “frequency tilt” in the transmission path. The Equalizer Mode indicates the strength of specific reflections, their location in relation to the test point location, and how hard the equalizer is working to correct them.
Digital Analysis (QAM View OPT4): Equalizer Mode A primary function of this mode is to help the user maintain low levels of equalizer stress by locating excessive equalization at specific QAM demodulator digital filter coefficients that require correction. Each vertical bar on the graph represents an equalizer filter coefficient. The highest bar represents the test point location, and the descending line to the right of this bar is the “high” mask.
Digital Analysis (QAM View OPT4): Equalizer Mode Fig. 9-20 EQUALIZER Main Screen The SDA will automatically attempt to lock-on to the QAM signal of the designated channel (or frequency). Lock errors may result from a variety of conditions, including improper unit configuration or cable connection. Connect the cable to the digital port on the unit before using any of the four digital modes.
Digital Analysis (QAM View OPT4): Equalizer Mode In-Channel Frequency Response Screen This screen is used to observe the signal amplitude in relation to the frequency. Use the arrow soft keys to adjust the position of the vertical markers. Press this key to select the In-Channel Frequency Response Screen (Fig. 9-21). Press this key to move to the LEVEL Submenu to edit the Reference Level or Scale Parameter of the graph. Fig.
Digital Analysis (QAM View OPT4): Equalizer Mode Fig. 9-22 In-Channel Group Delay Screen Press this key to return to the EQUALIZER Main Screen.
Chapter 10 Automatic Test INTRODUCTION Automated tests are easy and provide a convenient way of acquiring proofof-performance compliance data. Tests can be executed immediately or scheduled over a time period (to conserve battery life, the unit shuts itself off between scheduled intervals). When you’re configuring an Auto Test, you can record information about the location at which the test is being performed. Files can be created for commonly tested locations so you need enter the information only once.
Automatic Test: Test Locations 10 3. Enter a compensation value for local measurements. 4. Enter a name for the results file. 5. Select the type of test, either Immediate or Scheduled. 6. If a Scheduled test, set the schedule. 7. Enter the ambient temperature. While the Auto Test is in progress, the display indicates the measurement currently being performed (level, hum, modulation, etc.). Progress is displayed during the test. A bar graph on the display shows the percentage of completion.
Automatic Test: Test Locations or use the SteathWare Data Analysis software and download information to the unit. In either case the Auto Test Reports include test location data. 10 Parameters and Test Location Types Tables 10-1 and 10-2 provide information about the five types of test locations (Headend, Trunk Amp, Line Extender, Fiber Node, and Field Test), and the parameters that apply to each type. Table 10-1 lists the ten Units and Limits of Changes for each type.
Automatic Test: Test Locations Table 10-2 Parameters and Test Location Types 10 Parameter Trunk Head Extender Fiber Field Area ✔ ✔ ✔ ✔ Amp ID ✔ ✔ ✔ Power Configuration ✔ ✔ ✔ Feeder Maker Config ✔ ✔ ✔ Trunk Termination ✔ ✔ ✔ Voltage Setting ✔ ✔ ✔ Reverse Pad ✔ ✔ ✔ Reverse Equalizer ✔ ✔ ✔ Forward Pad ✔ ✔ Forward Equalizer ✔ ✔ Creating and Editing Test Locations Use the up and down diamond keys to select Test Locations from the main AUTOTEST menu, then press any s
Automatic Test: Test Locations 10 Fig. 10-2 The TEST LOCATIONS Screen Press the Step Back soft key at the upper left to return to the main AUTOTEST menu. Use the up and down diamond keys to scroll through the list and select an existing location. Entering a New Location To establish a new test location, perform the following steps: Press the Add Location soft key. The Edit Box appears and the program prompts you to name the location. Enter the name and press the Enter soft key.
Automatic Test: Performing an Auto Test screen shown in Fig. 10-3. If you are about to overwrite an existing location, the following warning appears: WARNING: A location with this name already exists. Overwrite? 10 Fig. 10-3 Editing Test Location Characteristics Scroll through the list of characteristics and make any necessary adjustments. When you are satisfied with the adjustments, press the OK soft key and the display returns to the main TEST LOCATIONS screen shown in Fig. 10-2.
Automatic Test: Performing an Auto Test information is stored in the Auto Test file along with the measurement data, and will be available during viewing and when you’re printing Auto Test results. This first screen presents you with a list of available locations. NOTE: If you are not interested in logging the information, select NONE from the list. The instrument will present you with only the steps required to configure the test. Fig.
Automatic Test: Performing an Auto Test 10 Location soft key (with the picture of a document going into a folder, near the top right of the screen) and enter a name for the location. When you are done editing, press OK to continue configuring the Auto Test. NOTE: The instrument reminds you when you have not stored the location. You need to store it only if you think you will return for another test. Fig.
Automatic Test: Performing an Auto Test 10 Fig. 10-6 Select Probe Points from this Screen You can log voltage measurements in the field using the MEASURE VOLTAGE screen shown in Fig. 10-7. These will appear when you’re viewing or printing the results of the Auto Test. When you have finished entering the measurements, press the OK soft key. Fig.
Automatic Test: Performing an Auto Test Compensation 10 Compensation is added directly to the signal level measurements. You can use this to compensate for losses associated with probe points found on certain amplifiers. The default is the value specified in the TESTPOINT screen. Enter a different value in the COMPENSATION screen shown in Fig. 10-8 if necessary, and press the OK soft key to continue. Fig.
Automatic Test: Performing an Auto Test 10 Fig. 10-9 The RESULTS FILE NAME Screen Type of Test Tests can be executed immediately or scheduled over a time period. You can select either by the Immediate or the Scheduled soft key. Set Schedule The screen shown in Fig. 10-10 will appear only if you have selected a scheduled test. The default schedule will perform tests at four intervals over a twenty-four hour period beginning with the present time and date.
Automatic Test: Performing an Auto Test 10 Fig. 10-10 The SET SCHEDULE Screen Temperature The ambient temperature at which the test is performed is recorded. The instrument contains an internal temperature sensor for this purpose. If you prefer, you can use your own thermometer and manually enter the temperature in the TEMPERATURE screen shown in Fig. 10-11. NOTE: For scheduled tests, the manual temperature entry is used for the first interval only.
Automatic Test: Auto Test Results 10 Fig. 10-11 The TEMPERATURE Screen When you are ready to begin the test, press the OK soft key. Canceling an Auto Test While performing an Auto Test, you will not be able to select other measurement modes without first canceling the test in progress. Doing this will result in an incomplete Auto Test. You will not be able to resume the previously configured test. Press the Cancel soft key to cancel the Auto Test.
Automatic Test: Auto Test Results • The Info soft key displays the test location characteristics for the selected file. This is the information that was logged when you configured the test. The items presented depend on the location type that you selected. 10 • When you have selected an Auto Test file, you are presented with a list of intervals that are contained within the file. The list includes the interval number, date, time, and temperature when the interval was recorded, and the Pass/Fail results.
Automatic Test: Auto Test Results #1 Date: Time: Temp: Chan #2 #3 #4 10 07/04/99 07/04/99 07/05/99 07/05/99 17:00:00 23:00:00 05:00:00 11:00:00 +75 F +61 F +59 F +83 F Carrier Type Video Level (dBmV) Video Level (dBmV) Video Level (dBmV) Video Level (dBmV) 24 Hr Deviation (dB) 2 * TV +9.6 +8.8 -17.7 LO +10.7 28.4 HI 3 * TV +9.9 +8.6 -5.8 LO +8.9 15.7 HI 4 TV +9.2 +8.3 -2.9 LO +10.1 13.0 HI 5 TV +9.3 +8.2 +9.3 +11.5 3.3 6 TV +8.1 +9.1 +8.6 +11.0 2.9 14 TV +9.7 +8.7 +9.0 +11.0 2.3 15 TV +9.3 +7.
Automatic Test: Auto Test Results NOTE: Channel 5 will always pass the adjacent channels test because it is not recognized as an adjacent channel with channel 4. 10 Viewing Intervals To view the measurement data from an interval, use the up and down diamond keys to highlight the interval then press the Load File soft key. The first screen displayed is a tabular list that includes the video and audio carrier levels along with the Delta V/A for each channel.
Automatic Test: Auto Test Results ------------------------------------------------------------------Location Name: 1028_ELM_ST Location Type: Trunk Test Point Type: Forward Trunk In Test Point Compensation: +0.0 dB ------------------------------------------------------------------Area: 00A7 Amp ID: 12-275Z Power Config: In Feeder Maker Config: 1 Trunk Termination: No Voltage Setting: Low Reverse Pad: +0.0 dB Reverse Equalizer: +0.0 dB Forward Pad: +0.0 dB Forward Equalizer: +0.
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Chapter 11 Files INTRODUCTION The SDA-5000 is equipped with non-volatile memory that is used to store data from field measurements for viewing at a later time. You can retain these files in the unit for later review, or, with Acterna’s StealthWare PC software, you can upload them to a PC. Files loaded on a PC can be viewed, printed, and archived with the computer. Additionally, these files can be downloaded to another SDA-5000 for viewing in the field.
Files: Storing Files • Spectrum scans—including regular, zero-span, and CSO/CTB measurements. Regular measurements can also include peak-hold values. • Tilt measurements • PathTrak measurements—including Local and Remote traces. Channel plans and Spectrum mode settings can be stored as files, too. 11 All the files stored in your unit exist in a common pool of non-volatile memory. When a file is stored, the instrument uses only the memory actually required for the data.
Files: Storing Files To store any one of these types of files, switch to File mode directly from the SCAN, SPECTRUM, TILT, SWEEP, or PATHTRAK measurement menu. Fig. 11-1 shows the FILE screen displayed from any of these modes. 1. Press the Function and 2 def keys while taking the measurement. The screen displays the FILE menu for that test type (see Fig. 11-1). The instrument displays a list of all files that are of the same type as the current measurement. 2. Press the Store File soft key.
Files: Viewing and Printing Files VIEWING AND PRINTING FILES To view stored measurement files, press the Function and 2 def keys. The MEASUREMENT FILES screen displays a list of all currently stored measurement files (see Fig. 11-2). Use the up and down diamond keys to select a file. Use the Load soft key to view the file. When you’re finished, press the Function and 2 def keys to return to the MEASUREMENT FILES screen. 11 Use this soft key to print the highlighted/marked file.
Files: Sweep References • TILT Tilt mode • SPECT Normal Spectrum Mode • ZSPAN Zero Span Mode • CSO CSO/CTB • F_CFG Spectrum Configuration (this stores settings for display purposes) • PTRAK PathTrak mode • SWPLS Sweepless sweep • LOOP Loopback sweep • QAM QAM Constellation files • Q_ING QAM Ingress measurements • DIGI Digital summary files • MODCN Modem Carrier-to-Noise files NOTE: QAM constellation files can take a long time to save and to view.
Files: Sweep References • SWPLS (Sweepless Sweep): In Sweepless Sweep, the instrument is completely passive, sweeping its receiver across the allotted spectrum. Only active carriers in the CATV system will register in the sweep. • LOOP (Loopback Sweep) (OPT2): In Loopback Sweep, the unit transmits a signal that it analyzes when it returns. 11 You can store a sweep reference after making a sweep measurement.
Files: Overlay Mode Different types of sweeps can be stored as references. The SDA instruments mark them differently, and display FDSWP for forward references, RVSWP for reverse references, LOOP for Loopback references, and SWPLS for Sweepless references. The file name and date stored are also shown for each file. If the channel plan has changed since a reference was stored, the reference is obsolete and can no longer be used.
Files: Overlay Mode 11 Fig. 11-4 A Sweep Reference with a Live Sweep In the file shown above, a ‘trap’ was added after the file was stored. It is very easy to see the change caused by the trap. You can also see the location of the trap in the sweep response. During a file overlay view, you can use the same controls normally available for sweep. Marker values are calculated from the current sweep response.
Files: Overlay Mode • The names of the file being viewed and the currently selected reference appear beneath the marker information. • The Level and Frequency adjustments affect both the stored and live sweeps. • Reference Limits Checking and Test Point Compensation affect the live sweep only. 11 • The marker values indicate the levels of the live sweep. • Auto Scale affects the live sweep data. • The stored sweep response display is a gray-filled area.
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Chapter 12 Maintenance MAINTAINING YOUR SDA EQUIPMENT This chapter covers routine tasks that a Service Technician can perform on the SDA instruments. Visual, Physical, and Mechanical Inspection Make sure all hardware is properly installed and tightened. RF Connector Replacement The RF connector attaches the unit to the cable system, and over time this frequent usage causes wear on the connectors and they should be replaced. To replace the connector: 1.
Maintenance: Maintaining Your SDA Equipment Battery Terminal Cleaning Clean the battery terminal regularly. You should examine it weekly for signs of corrosion or contamination. One acceptable method of cleaning it is to use a hard type eraser, such as one for erasing ink; do not use the soft "moldable" types. Charging the Battery 12 SDA field units come with an extended-life battery that you can charge with the supplied charger via the charger port on the battery housing (see Figure 12.1).
Maintenance: Worldwide Support, Sales, and Service Cleaning the Instrument Do not apply water directly to the instrument. Moisten a soft cloth with water and a gentle detergent, then wring any excess water out of it by hand until it is much too dry to drip. Wipe the instrument gently; dry the display screen to prevent spots. Do not use any type of cleanser or polish on the display! Annual Calibration This instrument should be calibrated annually to ensure accurate performance.
Maintenance: About Our Service Technical assistance centers (Continued) Region Phone Number Hours of Operation Europe, Africa, and Mid-East 00800 882 85822 (European Freephone) M-F, 8:30 a.m. - 5:00 p.m. GMT +800 882 85822 (Acterna UK) +49 (0) 7121 86 1262 (Acterna Germany) 12 +33 (0) 1 39 30 24 24 (Acterna France) Asia and the Pacific +852 2892 0990 (Hong Kong) M-F, 9:00 a.m. - 5:30 p.m. +86 10 6833 7477 (China) M-F, 9:00 a.m.- 5:30 p.m. +61 3 9690 6700 (Australia) M-F, 8:30 a.m. - 5:30 p.m.
Maintenance: About Our Service • Information on products and services, including upgrades, calibration, training, software enhancement agreements (SEAs), and product maintenance agreements. Our representatives can also provide assistance with product returns and repairs. • Expert technical support, including help with product configuration, circuit qualification, and complete network trouble sectionalization.
Maintenance: About Our Service Under time and material pricing, customers are billed for the actual cost of the repair, making this a cost-effective method for minor repairs. Under flat rate pricing, customers pay a fixed service charge to repair unit failures (excluding damage or abuse), resulting in simplified paperwork and easier budgeting. Consulting Services Our Consulting Services offer one of the broadest and most experienced resource portfolios in the communications testing industry.
Maintenance: About Our Service Technical training By providing both experienced instructors and a hands-on atmosphere, Acterna training is designed to optimize test strategies and employee development requirements.
Maintenance: About Our Service shipment to Customer. If Installation Services have not been ordered, the warranty period shall begin upon shipment to Customer. Hereafter these periods of time shall be collectively referred to as the “Initial Warranty Period.” 12 Acterna’s obligation and customer’s sole remedy under this Hardware Warranty is limited to the repair or replacement, at Acterna’s option, of the defective product.
Maintenance: About Our Service modified or is merged with other software by Customer or any third party or (b) all or any part of the Software is installed on any computer equipment other than the Designated Server or used with any operating system for which the Software is not designed. Services Warranty — Acterna warrants that the Services provided by Acterna, if any, shall be performed promptly, diligently and in a professional manner in accordance with the commercial standards of the industry.
Maintenance: About Our Service reference number on the outside of the package and ship it prepaid and insured to Acterna.
Chapter 13 Description and Basic Operation of the SDA-5500 and 5510 INTRODUCTION This chapter explains the user interface, basic operational modes, configuration, and printing capabilities of the SDA-5500 and SDA-5510. Not all the options covered are available on both headend units. In those cases where an option is only available on a particular unit, it will be noted.
Description and Basic Operation of the SDA-5500 and 5510: User Interface Elements • four diamond keys • sixteen numeric entry keys Soft Keys There are a total of eight soft keys, four on either side of the display (see Fig. 13-1). The function of each soft key changes depending on the particular operation being performed. The function is indicated by an icon that appears on the display next to the associated soft key. Soft keys are not always active.
Description and Basic Operation of the SDA-5500 and 5510: User Interface Elements Fig. 13-2 The Eight Measurement Mode Keys • LEVEL: Signal level measurements on individual channels are made by entering a specific channel number and pressing the channel key. Measurements can also be made by selecting the carrier with a marker in the Scan mode and pressing the Level key.
Description and Basic Operation of the SDA-5500 and 5510: User Interface Elements • SPECT: Provides a Spectrum Analyzer display, and CSO/CTB measurements. Support Mode Selection Keys Support modes are accessed using the support mode selection keys. There is a key for each of the four support functions. These keys are located to the right of the display and to the left of the diamond keys. • Nav: Press this key to access the Navigator interface. • Test: This key provides access to the main AUTOTEST menu.
Description and Basic Operation of the SDA-5500 and 5510: User Interface Elements Fig. 13-3 The Alphanumeric Keys Alpha Entry Mode Most numeric keys have alphabetic characters printed on them. These characters can be accessed when the alpha entry indicator appears in the title bar. In the alpha entry mode, a cursor appears below the active position. Repeated pressing of an alphanumeric key sequences through the values printed on the key.
Description and Basic Operation of the SDA-5500 and 5510: Global Configuration GLOBAL CONFIGURATION This section describes the six setup modes for the SDA-5500 and SDA-5510 accessible from the main CONFIGURE menu shown in Fig. 13-4: Global, Measurements, Channel Plan, Sweep Receiver, PathTrak, and Diagnostics. 13 Fig. 13-4 The Main CONFIGURE Menu (SDA-5500) Global setup allows you to configure aspects of the unit not specifically related to measurements.
Description and Basic Operation of the SDA-5500 and 5510: Global Configuration Fig. 13-5 The GLOBAL Configuration Menu 13 Operator Name: The Operator Name option allows the user to enter the operator’s name. This name will appear in the header section of the Auto Test report. Contrast Level: Use the Contrast Level option to adjust the contrast level of the LCD for optimum viewing. The level is adjustable on a scale from 1 to 15. Use the up and down diamond keys to adjust the contrast.
Description and Basic Operation of the SDA-5500 and 5510: Global Configuration Date: Select this option to enter the date using the numeric entry keys. The date will be displayed in the format you select in the DATE FORMAT setup menu. Printer: The Printer option sets the printer interface to the specific type of printer used. Use the up and down diamond keys to select the desired printer.
Description and Basic Operation of the SDA-5500 and 5510: Global Configuration CAUTION ! Executing this function will cause all saved files, functions, and memory to be lost. Display Test: This option allows you to test the operation of the display. With this option highlighted, press the Enter key and follow the instructions displayed.
Description and Basic Operation of the SDA-5500 and 5510: Global Configuration 13 Fig. 13-6 The MEASUREMENTS Setup Screen Temperature Units: Use the up and down diamond keys to select the desired temperature units in degrees Celsius or degrees Fahrenheit. Signal Level Units: Select the units to be used for checking signal power levels (dBmV, dBuV, and dBm). Frequency Tuning Step Size: Adjust the Tuning Step Size using the up and down diamond keys or the numeric entry keys (0.01 to 100.
Description and Basic Operation of the SDA-5500 and 5510: Global Configuration the OK soft key. The screen displays the noise floor, expressed in the currently selected units (e.g. dBmV). Channel Plan Setup Selecting the CHANNEL PLAN option from the CONFIGURE menu takes you to a screen where you can set nine (SDA-5510) or ten (SDA-5500) channel plan configuration options.
Description and Basic Operation of the SDA-5500 and 5510: Basic Modes of Operation • Enable live headend ingress • Reverse Telemetry Frequency • Reverse Sweep Plans See Also ½ Chapter 14, "SDA-5500/SDA-5510 Sweep Configuration," covers these options in detail.
Description and Basic Operation of the SDA-5500 and 5510: Basic Modes of Operation simultaneously. Alternatively, an individual carrier can be measured (as in the case for a data or pilot carrier), or the unit can be tuned to a specific frequency. Information displayed in the Level mode is as follows (numbers correspond to Fig. 13-7 callouts): 1. Channel number or frequency 2. Channel label (appears where indicated) 3. Video carrier frequency and level (numerical) 4.
Description and Basic Operation of the SDA-5500 and 5510: Basic Modes of Operation Tuning by Channel or Frequency When the level mode is selected, you can tune the unit by channel or by frequency. In the channel mode, the channel and channel label will appear at the top of the display. The left and right diamond keys can be used to decrement and increment the channels. Channels can also be entered using the numeric keys followed by the CHAN key.
Description and Basic Operation of the SDA-5500 and 5510: Basic Modes of Operation • Reference level and scale • Test point compensation (appears only if a nonzero value is programmed during setup) 13 Fig. 13-8 The TILT Measurement Screen When the TILT key is pressed the screen will automatically display up to nine video carrier levels that were defined in the EDIT CHANNEL PARAMETERS screen of the CHANNEL PLAN setup menu. The up and down diamond keys can be used to adjust the graph's reference level.
Description and Basic Operation of the SDA-5500 and 5510: Basic Modes of Operation Pressing the Auto Scale soft key will automatically set the reference level for an optimum Tilt display. The FCN and Scale key can also be used to automatically set the reference level. Scan Mode Use the Scan mode to get a good look at the whole spectrum of absolute carrier levels. In this mode, a bar graph showing all carrier levels is displayed (see Fig 13-9).
Description and Basic Operation of the SDA-5500 and 5510: Basic Modes of Operation When the SCAN key is pressed, a graph showing all carrier levels is displayed. Use the right and left diamond keys to position the marker to the desired channel. The channel numbers can also be entered directly using the numeric entry keys. The up and down diamond keys can be used to adjust the reference level of the graph. Level Adjustments Press the LVL soft key to edit the scale and reference level of the Scan display.
Description and Basic Operation of the SDA-5500 and 5510: Basic Modes of Operation Audio Carriers If desired, the audio carriers can be omitted resulting in a faster scan. This feature is selected in the MEASUREMENT setup menu. An indicator appears in the upper left hand corner of the Scan screen when audio carriers are omitted. Limits The Limits feature (Fig. 13-10) allows for comparison of the current scan measurement with the limits that are defined in setup.
Description and Basic Operation of the SDA-5500 and 5510: Basic Modes of Operation performed with each scan update. However, a Check soft key is provided to repeat the limit check whenever desired. The Limits On/Off soft key toggles the limit check feature on and off. When turned off, the limit annunciators do not appear.
Description and Basic Operation of the SDA-5500 and 5510: Basic Modes of Operation Fig. 13-11 The C/N Screen 13 To make a carrier to noise measurement, press the C/N measurement mode key. The C/N ratio of the tuned channel or frequency will be displayed. Bandwidth Adjustments To edit the bandwidth, press the BW soft key. The bandwidth can be adjusted by using the up and down diamond keys or by entering a value using the numeric keypad and then pressing the Enter key.
Description and Basic Operation of the SDA-5500 and 5510: Basic Modes of Operation Measuring Hum Hum is undesirable modulation of the television video carrier by power line frequencies and harmonics (e.g., 60 or 120 Hz), or other low frequency disturbances (FCC limit: < 3%). To measure hum, simply press the Hum key when tuned to any non-scrambled channel (see Fig. 13-12). In the Hum mode the hum modulation of the tuned channel or frequency will be displayed in either % or dB as selected by the operator.
Description and Basic Operation of the SDA-5500 and 5510: Basic Modes of Operation NOTE: The <1kHz setting does not include the 1Hz component, it only includes 50 to 1000Hz. CAUTION ! Hum measurements taken while the desktop charger is in use will affect the hum reading. For the most accurate reading, disconnect the charger prior to taking hum measurements.
Description and Basic Operation of the SDA-5500 and 5510: Basic Modes of Operation Fig. 13-14 The Audio MODULATION Screen 13 Use the up and down diamond soft keys to adjust the volume. Spectrum Analyzer Mode The spectrum analyzer display provides a view of the system spectrum with variable spans from 50 MHz to 3 MHz and a dynamic range of better than 60 dB. When the Spect key is pressed, the screen shown in Fig. 13-15 is displayed. Fig.
Description and Basic Operation of the SDA-5500 and 5510: Basic Modes of Operation Level Adjustments A LVL (level) soft key is used to adjust the vertical parameters of the graph. These parameters include Max Hold, Ref Level and Scale. The Max Hold function ensures that the highest signal over multiple sweeps is displayed. When the Max Hold soft key is pressed, as indicated in the left hand corner of the display, the highest signal level is displayed. The M1/M2 readings correspond to the max hold levels.
Description and Basic Operation of the SDA-5500 and 5510: Basic Modes of Operation How To Make CSO/CTB Measurements CSO (Composite Second Order) is a clustering of second order beats at any frequency in the spectrum, which causes interference to picture quality when they fall within the video bandwidth. CTB (Composite Triple Beat) is a clustering of third order distortion products usually around the video carrier frequency.
Description and Basic Operation of the SDA-5500 and 5510: Basic Modes of Operation Fig. 13-17 The CSO/CTB Measurement Screen 13 The light trace represents the carrier prior to it being turned off. The dark trace represents the distortion products. The measurement value is computed as a ratio of the peak level of the video carrier to the peak of the distortion products of the second and third order beats. The "worst case" CSO value is highlighted and is the overall CSO value.
Description and Basic Operation of the SDA-5500 and 5510: Basic Modes of Operation Fig. 13-18 The CSO SETUP Screen When exiting out of the CSO/CTB measurement, the unit will prompt you to turn the carrier back on.
Description and Basic Operation of the SDA-5500 and 5510: Basic Modes of Operation Fig. 13-19 The SWEEP Mode Screen (SDA-5500) 13 NOTE: Sweep telemetry will cease when another mode is selected. Sweep Mode (SDA-5510) The Sweep mode displays information about the current condition of noise and ingress in the headend and provides feedback to the field (see Fig. 1319 and 13-20).
Description and Basic Operation of the SDA-5500 and 5510: Basic Modes of Operation Fig. 13-20 The SWEEP Mode Screen (SDA-5510) The number of active users accessing return sweep information is indicated by the number of icons displayed below the level information. The SDA-5510 can handle up to 10 different technicians on the same headend unit. NOTE: Sweep telemetry will cease when another mode is selected. SDA-5510 operator information can be accessed by pressing the INFO soft key (Fig. 13-21).
Description and Basic Operation of the SDA-5500 and 5510: Basic Modes of Operation Fig. 13-21 The Operator Information Screen 13 Frequency Adjustments The FRQ soft key is used to set the start and stop frequency (for display purposes only). A Start and Stop soft key is displayed to select the parameter to be changed. You can be increment or decrement the frequency with the diamond keys, or enter a specific value using the numeric keys followed by the Enter key.
Description and Basic Operation of the SDA-5500 and 5510: Working with Files WORKING WITH FILES The SDA headend units are equipped with non-volatile memory that is used to store data from field measurements for viewing at a later time. You can retain these files in the unit for later review, or, with Acterna’s StealthWare PC software, you can upload them to a PC. Files loaded on a PC can be viewed, printed, and archived with the computer. The main FILE menu is shown in Fig. 13-22.
Description and Basic Operation of the SDA-5500 and 5510: Using Auto Test 2. Press the Store File soft key. The screen prompts you for a file name and warns if the name already is in use. 3. Press the Enter key. Use the keypad to enter a name, then press Enter again. The MEASUREMENT FILES screen is displayed (see Fig. 11-2). All stored files, except Sweep Reference files, can be uploaded to Acterna’s StealthWare PC software.
Description and Basic Operation of the SDA-5500 and 5510: Using Auto Test Fig. 13-23 The Main AUTO Menu 13 How To Create, Edit, and Delete Test Locations Test locations allow you to create specific test point location parameters for the Auto Test report (see Fig. 13-24). Test locations can be created directly on the SDA unit, or by using the StealthWare Data Analysis software and then downloaded to the SDA unit. The test location is used to identify where the data is collected.
Description and Basic Operation of the SDA-5500 and 5510: Using Auto Test Press the New soft key to create a new test location file (Fig. 13-25). The unit will then prompt you for a file name. After a name is entered, press the OK soft key. 13 Fig. 13-25 Naming a Test Location Each location in the list has an associated type along with values for the descriptive parameters. The parameters are shown in Table 13-1.
Description and Basic Operation of the SDA-5500 and 5510: Using Auto Test Table 13-1 Test Location Parameters and Values Parameter Minimum Maximum Default Area 15 character alpha-numeric field Amp ID 15 character alpha-numeric field Power Configuration Feeder Maker Config Trunk Termination Units IN / OUT/ THROUGH 1 9 1 NO YES NO Voltage Setting LOW / MID / HIGH Reverse Pad -100.0 +100.0 0.0 dB Reverse Equalizer -100.0 +100.0 0.0 dB Forward Pad -100.0 +100.0 0.
Description and Basic Operation of the SDA-5500 and 5510: Using Auto Test shows which of the parameters in the table above apply to each of the location types.
Description and Basic Operation of the SDA-5500 and 5510: Using Auto Test See Also ½ "Creating Channel Plans" (page 274) and "Reverse Sweep Channel Plans" (page 290) in Chapter 14 cover enabling these measurements. Tests can be made immediately or they can be made at timed intervals with the instrument sleeping between tests to conserve battery life. Upon test completion, the results can be viewed on the LCD display before printing or downloading to a PC.
Description and Basic Operation of the SDA-5500 and 5510: Using Auto Test Fig. 13-28 Configuring Auto Test Location Parameters 13 Press the Enter key after each parameter is entered to update the display. If changes are made and you want them updated in the location file, press the Save soft key. If changes are made and the Save soft key is not pressed, the changes will only affect the Auto Test that is about to be performed. Press the OK soft key when completed.
Description and Basic Operation of the SDA-5500 and 5510: Using Auto Test Fig. 13-29 Selecting the Test Point Type 13 When the desired Test Point type is selected, press the OK soft key. The following is a list of Test Point types available: Trunk Amp: Forward Trunk In Forward Trunk Out Bridger Reverse Trunk In Reverse Trunk Out Line Extended: Line Extended In Line Extended Out Voltage Measurements Use the numeric entry keys to enter the following system voltage measurements (Fig.
Description and Basic Operation of the SDA-5500 and 5510: Using Auto Test Fig. 13-30 Entering System Voltage Measurements 13 The voltage measurements are printed in the Auto Test report. Press the OK soft key when you’re done. Test Point Compensation Test Point Compensation is used to account for loses associated with certain amplifiers. Use the up and down arrow keys or the numeric entry keys to enter the Test Point Compensation (Fig. 13-31). (-100.0 to +100.0 dB in 0.1 dB steps). Fig.
Description and Basic Operation of the SDA-5500 and 5510: Using Auto Test Press the OK soft key when the desired value has been entered. Results File Enter a name for the Auto Test results file (Fig 13-32). 13 Fig. 13-32 Naming the Results File If you enter an existing file name, a warning message will appear prompting you to overwrite the existing file or create a new one. When the desired file name has been entered, press the OK soft key to proceed with the Auto Test.
Description and Basic Operation of the SDA-5500 and 5510: Using Auto Test Fig. 13-33 The AUTO TEST IN PROGRESS Screen 13 While the Auto Test is in progress, the measurement currently being performed (i.e. Level, C/N, Hum, or Modulation) is indicated on the screen Fig. 13-33). A bar graph showing the percentage of completion is displayed. Scheduled If the Scheduled mode is selected, the start, stop, and interval information must be entered prior to commencing the Auto Test (Fig 13-34). Fig.
Description and Basic Operation of the SDA-5500 and 5510: Using Auto Test Using the numeric entry keys, enter the start and stop information for the date and time as well as the interval amount. Press the Enter key after each parameter is entered to update the display. Use the up and down arrow keys to select the parameter to be entered. Press the OK soft key to commence the Schedule Auto Test. If the first interval is to commence immediately, the unit will prompt you to enter the ambient temperature.
Description and Basic Operation of the SDA-5500 and 5510: Using Auto Test Fig. 13-36 The Auto Test Results Mode 13 A table with all testing intervals and test site information is now displayed. If the Auto Test was performed immediately, then only one interval is displayed. If the Auto Test was performed using scheduled intervals, then all the interval numbers are displayed (Fig. 13-37). The Print All soft key is used to send all intervals in the directory to the printer.
Description and Basic Operation of the SDA-5500 and 5510: Using Auto Test Fig. 13-37 Interval Auto Test Results An X in the Pass/Fail column indicates an overall failure of the measurements taken during that interval. A check mark indicates that all measurements were within the specified limits. The 24hr Report soft key is provided to comply with FCC 24 hour testing requirements.
Description and Basic Operation of the SDA-5500 and 5510: Using Auto Test ------------------------------------------------------------------AC Voltage: 110 V DC Voltage (reg): 14.8 V (unreg): 20.
Description and Basic Operation of the SDA-5500 and 5510: Using Auto Test next to the reading indicating the direction that the measurement was out of specification. Each interval can be selected and viewed as desired. Use the up and down arrow keys followed by the View soft key to view specific interval test results (Fig.13-38). 13 Fig. 13-38 Viewing Interval Test Results The test results along with the limits comparison is displayed.
Description and Basic Operation of the SDA-5500 and 5510: Using Auto Test Fig.
Description and Basic Operation of the SDA-5500 and 5510: Using Auto Test Forward Pad: +0.0 dB Forward Equalizer: +0.0 dB ------------------------------------------------------------------AC Voltage: 110 V DC Voltage (reg): 14.8 V (unreg): 20.9 V ------------------------------------------------------------------Chan Label Video Audio Delta V/AC/N Hum Mod (dBmV) (dBmV) (dB) (dB) (%) (%) 2 * QVC -17.7 LO -18.4 0.7 LO 43.9 1.4 86.3 3 * TNN -5.8 LO -13.9 8.1 ------4 USA -2.9 LO -15.6 12.7 --0.9 --5 * ESPN +0.
Description and Basic Operation of the SDA-5500 and 5510: Status STATUS To view the Status screen, press the FCN and Status keys. The Status screen provides unit information (Fig.13-40). 13 Fig. 13-40 The SDA-5500 Status Screen An important feature is the amount of memory currently being used. This allows the user to decide if unwanted files should to be deleted to make more memory available for newer files.
Chapter 14 SDA-5500/SDA-5510 Sweep Configuration INTRODUCTION This chapter tells how to connect to a headend for sweeping and details all procedures involved in setup and use, for system commissioning and for maintenance. It concludes with coverage of the history and theory of sweeping.
IN OUT SDA 5500 Lasers / D istribution Amps PAD PAD Combining Network SDA-5500/SDA-5510 Sweep Configuration: Forward Sweep Configuration (SDA-5500) Note: Pads can be omitted if they’re not needed for proper levels. SDA 5500 Lasers/Distribution Amps IN OUT PAD Combining Network 14 PAD Fig. 14-1 Wiring for SDA-5500 Forward-only Sweep Note: Pads can be omitted if they’re not needed for proper levels. Fig.
SDA-5500/SDA-5510 Sweep Configuration: Forward Sweep Configuration (SDA-5500) The SDA-5500’s output can be injected using a directional coupler at the output of the combining network, or it can be injected at an input to the combining network. With an output level set such that the sweep is 14 to 16 dB below video carrier level, good response measurements can be made without interference to subscriber TV pictures.
SDA-5500/SDA-5510 Sweep Configuration: Forward Sweep Configuration (SDA-5500) Fig. 14-3 Relationship of Video Carriers, Sweep Insertion Point, and Forward Telemetry Signals The following worksheets will help you calculate the required levels for SDA5500 forward sweep. 14 Worksheet 1 Input Level Calculation 1. Enter the system level at the tap-off point (video carrier level) 2. Subtract the directional coupler (DC) value 3. Subtract the pad value 4.
SDA-5500/SDA-5510 Sweep Configuration: Forward Sweep Configuration (SDA-5500) Worksheet 2 Output Level Calculation 1. Enter the system level at the sweep injection point (video carrier level) 2. Subtract the relative level of sweep points (-15dB recommended) 3. Add the directional coupler (DC) value 4. Add the pad value Sweep output level (must be between +20dBmV and +50dBmV for high output level SDA-5500 units) Worksheet 3 Sweep Level Calculation 1.
SDA-5500/SDA-5510 Sweep Configuration: Forward Sweep Configuration (SDA-5500) Fig. 14-4 The SWEEP TRANSCEIVER Main Menu Use the up and down arrow keys or the numeric keypad to enter the telemetry frequency. 14 Do not place the telemetry signal too close to the diplex filter cut-off frequency in that roll-off may attenuate the telemetry signal to the degree that communication fails. This same caution applies to placing the signal in the high end roll-off region.
SDA-5500/SDA-5510 Sweep Configuration: Forward Sweep Configuration (SDA-5500) Use the up and down arrow keys or the numeric keypad to enter the sweep insertion level (20-50 dBmV). Include Audio Carriers This selection allows the audio carriers to be excluded resulting in a faster sweep. Use the up and down arrow keys to include (Yes) or exclude (No) audio carriers. Enable or Disable Reverse Sweep When Reverse Sweep is enabled, both Forward and Reverse sweeping can be performed.
SDA-5500/SDA-5510 Sweep Configuration: Forward Sweep Configuration (SDA-5500) See Also ½ For more information about reverse sweep plans, see "Reverse Sweep Channel Plans" (page 290). Creating Channel Plans After the transmitter is properly connected, the next step is to build a channel plan. This channel plan will designate which channels are active in the system, which channels are scrambled, and which channels are inactive and therefore can be converted to sweep injection points.
SDA-5500/SDA-5510 Sweep Configuration: Forward Sweep Configuration (SDA-5500) The soft key next to the chevron icon in the upper left takes you back to the main CHANNEL PLAN menu. 3. From the CHANNEL PLAN menu, highlight Select Channel Plan, and press the Enter key. 4. Press the designated soft key, then choose NCTA plan. At this point ignore the File Icon and the Information Icon, and return to the CHANNEL PLAN menu.
SDA-5500/SDA-5510 Sweep Configuration: Forward Sweep Configuration (SDA-5500) Fig. 14-5 The Channel Plan Main Menu Options available in this list include: • Select Channel Plan: Press the Enter key to call up a list of existing channel plans. If the unit is being used for the first time, the only channel plan available will be the standard NCTA plan. Use the up and down arrow keys to scroll through the list.
SDA-5500/SDA-5510 Sweep Configuration: Forward Sweep Configuration (SDA-5500) • Channel Tuning Sequence: Use the up and down arrow keys to select either numeric order or frequency order for the channel tuning sequence. • Build Channel Plan: Press the Enter key to begin the Build Channel Plan sequence. This sequence allows the user to create a channel plan by "learning" the channels on a cable system. Ensure that the SDA-5500 is connected to the cable system.
SDA-5500/SDA-5510 Sweep Configuration: Forward Sweep Configuration (SDA-5500) 1. From the main CHANNEL PLAN menu, scroll to Edit Channel Plan and press ENTER. A listing of all the channels within the frequency range designated in the Build Channel Plan phase will appear on the screen. Notice that there are columns for enabled, channel type, channel number, label, frequency (video carrier), sweep, tilt, and scrambled. 2.
SDA-5500/SDA-5510 Sweep Configuration: Forward Sweep Configuration (SDA-5500) Single Carrier - Can be used for an FM or data carrier or CW. Sweep Insertion Point - Used to insert sweep points into vacant spectrum areas. Digital Carrier - Can be used for digital carrier power measurement. Only supported in the Level, Sweep, and Spectrum measurement modes. An RMS detection mode is used when measuring the level of a digital channel.
SDA-5500/SDA-5510 Sweep Configuration: Forward Sweep Configuration (SDA-5500) • Scrambled: Select Yes if the channel is scrambled. When a channel is designated as scrambled, the sweep will only look at the video carrier as a sweep reference, instead of both the video and audio carrier. Note: a diamond will appear to the left of the channel type indicator on most screens. • Audio Offset: Specifies the audio offset of the channel.
SDA-5500/SDA-5510 Sweep Configuration: Forward Sweep Configuration (SDA-5500) 827.63 to 827.87 lower to 827.62 882.63 to 882.87 lower to 882.62 938.13 to 938.37 lower to 938.12 • Specify Auto Measurements: Press the Enter key to specify the measurements to be taken during the performance of an Auto Test (see Fig. 14-7). This feature allows the user to specify which channels C/N, Hum, and Modulation measurements are made on. 14 Fig.
SDA-5500/SDA-5510 Sweep Configuration: Forward Sweep Configuration (SDA-5500) Fig. 14-8 The EDIT LIMITS Screen • Use the up and down arrow keys to select the limit to be edited. Use the numeric entry keys or the up and down arrow keys to enter a value. Once the value has been entered, press the Enter key to update the display. 14 • Copy Remote Plan: This selection allows you to copy a channel plan from one unit to another (Fig. 14-9). Fig.
SDA-5500/SDA-5510 Sweep Configuration: Forward Sweep Configuration (SDA-5500) Connect a special Acterna cable between the serial ports of two units. Ensure that the baud rate is set the same for each unit. A baud rate of 19.2K is recommended for uploading plans. Select Copy Remote Plan from the menu and press the Enter key. A list of plans located in the remote units memory will appear. Select the plan that you want to copy and press the Copy soft key.
SDA-5500/SDA-5510 Sweep Configuration: Configuring Reverse Sweep • Using the TX diagnostics menu of the SDA-5500, generate a CW signal at the same level and frequency that will be used for forward telemetry. Use the Frequency mode of the SDA-5000 to measure this telemetry level. It should be 10dB below video signal levels. Verify that when the CW transmission stops, the level drops by at least 20dB.
SDA-5500/SDA-5510 Sweep Configuration: Configuring Reverse Sweep sweeping in the forward direction will experience a slightly slower sweep time. Basic Reverse Sweep Procedure Sweeping the reverse path is a little different from sweeping the forward path. Because the system is designed with appropriate spacing for the forward high frequency range, the reverse path may not require amplification at each station. The lower frequencies aren’t attenuated in cable as much at the higher frequencies.
SDA-5500/SDA-5510 Sweep Configuration: Configuring Reverse Sweep Combining Network out SDA-5500 or SDA-5510 in Store a reference here before aligning field amplifiers Align forward and reverse at this test Check here to point make sure cable is good before aligning amplifier SDA-5000 Fig. 14-10 Single Cable – Split Band Network Reverse Sweep Configuration With Bi-Directional Test Points.
SDA-5500/SDA-5510 Sweep Configuration: Configuring Reverse Sweep Distribution Amplifiers Combining Network in in out out SDA-5500 or SDA-5510 SDA-5000 Fig. 14-11 Single Cable – Split Band Network Reverse Sweep Configuration With Bi-Directional Test Points. Systems with directional test points are set up as shown in Figure 14-11. The directional coupler on the input side should be designed for at least the frequency range of the forward bandwidth of the network under test.
Lasers or Distribution Amps IN SDA-5500 PAD OUT IN Optical Rcvr or Combiners OUT AD AD AD Combining Network SDA-5500/SDA-5510 Sweep Configuration: Configuring Reverse Sweep Forward Path Lines TP Reverse Path Lines TP IN OUT SDA-5510 SDA-5000 Note: Pads may be omitted if not required for proper levels. Reverse path ALC must be turned off. 14 Fig.
SDA-5500/SDA-5510 Sweep Configuration: Configuring Reverse Sweep NOTE: Reverse sweep should be disabled when no SDA5000 OPT1 units are being used. This will optimize the update rate of the forward sweep. It can also be disabled if you are using the SDA-5510 for reverse sweeping. Setting the Forward Telemetry Frequency (SDA-5510) Use the up and down keys to enter the forward telemetry frequency.
SDA-5500/SDA-5510 Sweep Configuration: Configuring Reverse Sweep During reverse sweeping using only the SDA-5500 in the headend, the level of the telemetry (the telemetry coming back upstream from the SDA-5000) needs to hit the input of the SDA-5500 at 0 dBmV +/-10 dB. You can verify this easily by checking the telemetry level in the lower right corner of the display. Again, if additional attenuation is required, you can use an in-line pad on the low side of the diplex filter.
SDA-5500/SDA-5510 Sweep Configuration: Configuring Reverse Sweep • The best way to set up the reverse sweep channel plan is to build a plan with 250 kHz sweep insertion points from 5 to 45 MHz and then delete points that fall within the service frequencies. A close look at the peak held scan, using a marker, may indicate frequencies within the bands specified above for insertion points (34.5 MHz, for example). 14 Fig. 14-13 Max-Held Spectrum Display Creating a New Reverse Sweep Channel Plan 1.
SDA-5500/SDA-5510 Sweep Configuration: Configuring Reverse Sweep Fig. 14-14 Creating a New Reverse Sweep Plan, Step 1 2. Enter the start frequency (see Figure 14-15). This will be the frequency of the first sweep point in the plan. Use the numeric keys followed by the ENTER key. Then press the OK soft key to continue. 14 Fig. 14-15 Creating a New Reverse Sweep Plan, Step 2 3. 292 Enter the interval (see Figure 14-16). This interval determines the spacing between sweep points.
SDA-5500/SDA-5510 Sweep Configuration: Configuring Reverse Sweep Fig. 14-16 Creating a New Reverse Sweep Plan, Step 3 4. Finally, enter the stop frequency (see Figure 14-17). There will be no sweep points generated beyond the stop frequency. Use the numeric keys followed by the ENTER key. Then press the OK soft key to continue. Fig.
SDA-5500/SDA-5510 Sweep Configuration: Configuring Reverse Sweep Sweep points are generated beginning at the start frequency and continuing until the stop frequency is reached. The frequency of each point is calculated by adding the step interval to the frequency of the previous point. After it has been created, the new plan will appear in the REVERSE SWEEP PLAN list. Selecting an Existing Reverse Sweep Plan The REVERSE SWEEP PLAN screen presents a list of all reverse sweep plans stored in memory.
SDA-5500/SDA-5510 Sweep Configuration: Configuring Reverse Sweep Fig. 14-18 The EDIT REVERSE PLAN Screen 3. Notice that the frequency of the selected sweep point also appears in the Edit Box below the list. You can change the frequency by using the numeric keys followed by the Enter key. The list will be updated when the Enter key is pressed. 4. To remove a sweep point, use the up or down keys to select the point, then press the Delete soft key. 5.
SDA-5500/SDA-5510 Sweep Configuration: Forward and Reverse Sweep (SDA-5500) 2. Set the reverse telemetry and sweep levels of the SDA-5000 so that, in the combining network, they will be about 10dB below the reverse path signal levels. Make sure that test point compensation is set to 0 for this test. 3. Using the TX diagnostics menu in the SDA-5000, generate a CW signal at the same level and frequency as the telemetry. Verify that the expected level reaches the SDA-5500 or SDA-5510 used for reverse sweep.
SDA-5500/SDA-5510 Sweep Configuration: Using Both Headend Units SDA-5500 Fig. 14-20 A Second Method of Connecting the SDA-5500 for Forward and Reverse Sweep 14 USING BOTH HEADEND UNITS The addition of the SDA-5510 to the Stealth sweep system takes the responsibility for reverse sweep away from the SDA-5500, and serves to speed both forward and reverse sweep rates.
SDA-5500/SDA-5510 Sweep Configuration: Sweep History and Theory Forward Combining Network out in Nodes Reverse Node Combiner SDA-5500 SDA-5000 out in SDA-5510 Fig. 14-21 Connecting an SDA-5510 in a System with an SDA-5500 14 SWEEP HISTORY AND THEORY What is sweep testing, and why do it? The most accurate way to align a cable network for either forward or reverse services is to ‘sweep’ the system.
SDA-5500/SDA-5510 Sweep Configuration: Sweep History and Theory A sweep transmitter injects a signal of a known level and frequency at the input of the network. At the output of the network, a receiver measures the level at the transmitter’s frequency and saves it in a table. Plotting the level at each frequency makes it possible to calculate the frequency response of the network. This is the most basic definition of sweep.
SDA-5500/SDA-5510 Sweep Configuration: Sweep History and Theory channel. The only element that must be configured to match receiver and transmitter prior to starting a sweep is the telemetry frequency. Stealth Sweep Early cable sweep systems worked by injecting sweep pulses at the points to be measured. Unfortunately, the pulses generated by sweep transmitters interfered with the video channels that customers were paying to watch.
SDA-5500/SDA-5510 Sweep Configuration: Sweep History and Theory Another difference between forward and reverse sweep alignment is that signals in a reverse path plant are TDMA digital channels: multiple transmitters are sending to one receiver at the headend. For these systems to work, the reverse carriers must be turned off when not in use. Accordingly, the sweep methodology that allows accurate forward path sweep without injecting any signal cannot be used here. Sweep pulses must be injected.
SDA-5500/SDA-5510 Sweep Configuration: Sweep History and Theory should be within N/10+X dB of flat at its output. Stealth sweep can automatically calculate whether an amplifier passes this test. X is set in the SWEEP configuration menu as the Sweep Limit Variable. Within the sweep display, entering the Limit Check mode allows the amplifier number (N) to be set. A limits check box appears with a check mark for a good amp, and an X for a bad one.
SDA-5500/SDA-5510 Sweep Configuration: Sweep History and Theory receiver used for later alignments also enables cancellation of absolute value meter errors. The absolute error at C will be almost the same as the error at B. If B is used as a perfect reference, then any absolute level error will be adjusted out. In order to maximize this effect, Acterna recommends that you frequently refresh the reference to be used in sweep testing (at least once a shift).
SDA-5500/SDA-5510 Sweep Configuration: Sweep History and Theory relative readings among several system test points and to allow referencing to cancel some errors. For this reason, sweep systems usually do not display absolute levels. Acterna’s Stealth sweep, however, has adapted the reverse sweep system to provide the right information for quick alignment of reverse gain and tilt. The screen displays absolute values for injection levels and headend receiver levels at high and low frequency tilt markers.
SDA-5500/SDA-5510 Sweep Configuration: Sweep History and Theory Another use for this information is to see whether noise is blocking the reverse telemetry. By checking the reverse telemetry frequency of the spectrum data, you can find out if a rogue signal has leaked into the network and disabled reverse sweep. You can also use the reverse spectrum display to be certain that the reverse connection is still intact. A CW signal can be injected at an unused frequency.
SDA-5500/SDA-5510 Sweep Configuration: Sweep History and Theory See Also ½ For more information about reverse path troubleshooting, see Chapter 5. • With both transmitters active, a different reverse sweep plan can be used with each. If different types of information are required, try the following procedure. The SDA-5510 can be set up for a sweep point every 1mHz of reverse bandwidth to get fast sweep updates.
Appendix A Application Notes FORWARD SWEEP AND BALANCE Step-by-Step Headend Setup for Forward Sweep Forward Sweep Setup A diplex filter is used to combine reverse signals into the rack mount unit instead of a splitter or DC-12 because of isolation issues, and the return fiber receiver is more than likely 5-200 MHz. This could cause jitter on the forward sweep if not properly set up.
Application Notes: Forward Sweep and Balance Tx=Stealth Headend Transmitter Rx=Multiple User Reverse Receiver Build Channel Plan (Configure; Channel Plan) If a channel plan has already been made, choose it from the list under "Select Channel Plan". NOTE: The newest Stealth field meter replaced many of the menus with icons. The "Setup" button has been replaced with a "Configure" mode, which can be accessed through the "Navigator" mode, or by pressing "func" (green key) and the number 3 key.
Application Notes: Forward Sweep and Balance d. Enter Tilt Channels (yes) 3. Edit Channel Parameters Enable or disable channels appropriately Enter tilt channels, sweep channels and/or scrambled channels Enter the type of channel (CW = Single, TV, Dual, Digital, Sweep Insertion Point) TIP: When making labels, the up and down diamond keys can be used to access special symbols.
Application Notes: Forward Sweep and Balance downstream spectrum. The factory default is 51 MHz on the Tx and 52 MHz on the Rx. NOTE: If diplex filters in the actives have a sharp roll-off, it may be wise to move the telemetry to a frequency that is more reliable. Forward Telemetry Level determines the level of the telemetry signal (FSK). This should be set 10 dB below the video reference level. The telemetry level is adjustable from 20-50 dBmV in 2 dB increments.
Application Notes: Forward Sweep and Balance cable pin configure). Also be sure that the Baud rate is identical on both pieces of equipment. NOTE: The headend unit’s channel plan does not have to be downloaded to the Stealth field unit to achieve sweep. Only the telemetry has to be the same. The channel plan affects the other measurement modes. NOTE: If a channel plan is made on the SDA field meter and copied to the Tx, the Tx will freeze up and must be shut off to reset.
Application Notes: Forward Sweep and Balance A forward sweep reference can also be taken at this time. Press “func” and “6” and enter a name for your reference. Some systems may want to use this reference for tap output responses. NOTE: Be careful with forward fiber optic transmitters in the headend. The test point may be aligned for the input to the "box" or the actual input to the laser diode. This could give a faulty reference. TIP: The Tilt mode is simple and makes selecting EQ very easy.
Application Notes: Forward Sweep and Balance NOTE: The "max/min" displays the peak-to-valley between the markers. The delta displays the difference in level and frequency at the markers. In forward sweep, the field unit has a max input of approximately 20 dBmV/ch for a fully loaded system. This is usually not a problem on the high loss test points, but could be an issue when connecting directly to a seizure screw. 256-QAM is a more complex modulation scheme and requires a higher C/N than 64-QAM.
Application Notes: Forward Sweep and Balance No Communication • Verify the appropriate telemetry; keep it high and located in the passband. Watch out for sharp diplex filter roll-off and old 550 MHz passives in a 750 MHz system. The minimum level for telemetry is approximately 15 dBmV and the max is approximately +12 dBmV. We sometimes lose communication on input test points because of the lack of gain from the active and the test point loss.
Application Notes: Forward Sweep and Balance • Disable all audio readings; only use single insertion points (CONFIGURE; SWEEP TRANSCEIVER.) • Place sweep points in the lower sideband of analog channels, especially sync suppressed scrambled channels, and in the guardband of digital channels. 1.1 MHz below the analog channels seems to be the "sweet spot”. Dwell times are set at 4 ms for a standard channel, 2.8 ms for a sweep point, and 158 ms for a scrambled or digital channel.
Application Notes: Forward Sweep and Balance • Balancing inactive plant; One could insert the receiver transmitter into the node where the optical receiver usually inserts. Store a reference at the Node output. Proceed to the next active in cascade and balance back to the same reference line and telemetry level, which was achieved at the node. This is assuming that the next amplifier will be running the same tilt and output levels as the node. Otherwise, offset accordingly.
Application Notes: Forward Sweep and Balance 8. The defacto standard is 2 dB/div for sweeping and 10 dB/div for spectrum analyzer viewing. 9. Version 9.3 firmware has added a few features worth mentioning. There is a hard key for Test Point Compensation (func. 7) a hard key to Select Previous Screen (func. 1) and Password Protection. Also, the spectrum analyzer is faster and has variable dwell times (only in the latest generation of Stealth and 4040D meters). 10.
Application Notes: Reverse Sweep and Balance REVERSE SWEEP AND BALANCE Step-by-Step Headend Set Up Reverse Sweep Setup A diplex filter is used to combine the reverse signals into the rack mount unit, instead of a splitter or DC-12, because of isolation issues and the return fiber receiver is more than likely 5-200 MHz. This could cause jitter on the forward sweep if not set up properly.
Application Notes: Reverse Sweep and Balance A TIP: When making labels, the up and down diamond keys can be used to access special symbols. Build Channel Plan (Configure; Channel Plan) NOTE: The newest Stealth field meter replaced many of the menus with icons. The "Setup" button has been replaced with a "Configuration" mode, which can be accessed through the "Navigator" mode or by pressing "func" (green key) and the number 3 key. Channel plan and file names are limited to 15 characters.
Application Notes: Reverse Sweep and Balance Sweep Transceiver (Configure; Sweep Transceiver). Forward Telemetry Frequency must be in the vacant spectrum and at least 500 kHz from any other carrier; must also be within the bandwidth of the downstream spectrum. The factory default is 51 MHz on the Tx and 52 MHz on the Rx. NOTE: If diplex filters in the actives have a sharp roll-off, it may be wise to move the telemetry to a frequency that is more reliable.
Application Notes: Reverse Sweep and Balance NOTE: Select “func” and “7” to enter the Test Point compensation. There is a toggle button to select forward or reverse Test Point compensation. Before You Leave the Headend On the receiver select (CONFIGURE; SWEEP RECEIVER) and set the forward sweep telemetry frequency to be the same as the Tx and/or Rx. Also set the reverse sweep insertion and telemetry levels as close to the system specifications as possible, taking into consideration insertion losses.
Application Notes: Reverse Sweep and Balance the sequence: (“func” and “6”). A name must be entered for your reference. Take a normalized reference at the node and at each leg if warranted. NOTE: It’s good to compare "apples" to "apples". Don’t change things like in-line pads and test leads once a reference has been stored. Store a new reference otherwise. If you use the internal, directional test point, it must be an injection test point.
Application Notes: Reverse Sweep and Balance into account extra accessory losses such as internal "feedermakers" and input pads if warranted. The reasoning behind constant inputs to the port vs. hybrid is beyond the scope of this application note. The reference line on the display should also be X dB. Look at M1 and M2 on the Stealth field unit display to verify. The "Ref" on the sweep display is the middle graticule line, not the actual sweep level.
Application Notes: Reverse Sweep and Balance Find the highest number and set the Sweep and Telemetry close to this. For instance, the highest number is 45.5 so they are set for 46 dBmV. Store a reference at the node with a 7 dB in-line pad installed. This will automatically knock down the sweep and telemetry level without having to change the generator output and the associated problems with doing that (explained later). Store a reference and record the telemetry.
Application Notes: Reverse Sweep and Balance • Use a plug-in test point, not a probe. Probes will always be bi-directional unless they are in series with the circuit and a directional coupler is used. • Keep all proceeding actives terminated for return sweeping. Don’t prestuff the reverse pad and EQ. The noise funneling may hamper your ability to sweep properly. A high value pad or terminator is recommended. • Terminate all low value tap ports.
Application Notes: Reverse Sweep and Balance noise floor level on the reverse input and compare with the reverse output. It should be higher by the amount of gain of the amplifier, but not necessarily. The noise reading could be affected by the test equipment noise floor. It may be warranted to inject a carrier and read the output to verify continuity. Use "Diagnostics" to send a CW carrier to the headend. Have someone in the headend use the Tx “Level” mode to read the reverse carrier level.
Application Notes: Reverse Sweep and Balance Faster Reverse Sweep • Make a bogus forward sweep plan on the Tx with only 1 sweep point. By sweeping the forward faster, the reverse will also be faster, but forward sweep will not be usable. • Use a Rx for up to 10 concurrent sweepers. This will decrease the probability of collisions with other sweepers off the same device. It also eliminates the chance of forward level overload.
Application Notes: Reverse Sweep and Balance NOTE: You must leave the field unit in this mode for the Tx to stay active. The cable must be attached to the "OPT" port on the field unit. A 2. The field unit is dc blocking to 200V peak-to-peak. This equates to approximately 100 Vac. 3. Once a trace is stored, you can alter the dB/div, start & stop freq., etc. To print this altered trace, hit "Func" & "Print". (Use the printer serial cable supported by Acterna.) 4.
Application Notes: Return Path Troubleshooting 14. The number of sweep points is limited to 500, but inserting too many points will make the refresh of the sweep display slower. The sweep update time is dependent on the setup. RETURN PATH TROUBLESHOOTING History of CPD CPD is created by non-linear mixing from a diode junction created by corrosion and dissimilar metal contacts. It’s caused not by just dissimilar metals, but also by dissimilar metal groups.
Application Notes: Return Path Troubleshooting down. The same thing can happen in customer installed passives unless they have voltage blocking capacitors installed. Troubleshooting CPD • Pull a forward pad to see if the return "cleans-up". This is definitely CPD, but very intrusive when doing this and may disrupt CPD temporarily. • Try not to disturb anything in this tracking process. Vibrations and movement can temporarily "break away" the diode/corrosion causing this CPD.
Application Notes: Return Path Troubleshooting The preamp is used to raise the signal above the noise floor of the test equipment. This is especially a problem on the return signals that are read from high loss test points. The SDA-5000 has a preamp built-in and compensates all measurements accordingly. If the problem is at the output of a tap when testing at the seizure screw, continue on. Some new probes from SignalVision and Gilbert create a good ground and quick connect.
Application Notes: Return Path Troubleshooting misleading. If there’s a reference carrier present, you can make a relative measurement, such as desired-toundesired ratio (D/U). The field unit has a "noise/ingress" feature, which can be used for troubleshooting. This displays the noise seen in the headend with optimum resolution of 280 kHz. This simplifies reverse troubleshooting and testing of headend reverse noise or ingress.
Application Notes: Return Path Troubleshooting Return Path Egress/Ingress Testing The FCC states that the maximum allowable limit for egress from dc up to 54 MHz is 15 µV/m at 30 meters. By utilizing forward path egress techniques, it may be possible to characterize the return path ingress points to some extent. Testing stringently at 5-10 uV/m everywhere, including the drops, is probably a better indication of return path integrity. Forward path leakage does not necessarily equal ingress, however.
Application Notes: Return Path Troubleshooting Fig. Reverse ingress spectrum trace after 30 sec. with traditional settings. A Fig. Reverse ingress spectrum trace after 6 sec. with dwell time = 20 ms. The "Zero Span" Mode In this mode, you can view desired-to-undesired ratios and see peak bursts of TDMA data.
Application Notes: Proofing and Testing periods & collisions, and see ingress in the data packet without taking the service off-line. Refer to the Feb. ’99 issue of Acterna’s bi-annual newsletter, Wavelengths. PROOFING AND TESTING FCC Title 47 Code of Federal Regulations, Subpart K, Section 76.605(a) Records must be kept on file for 5 years and they must be open to the FCC or the local franchiser upon request. Rule 76.
Application Notes: Proofing and Testing The video level for each channel at the end of a 100 foot drop will have: • > 3 dBmV [76.605(a)(3)]. • < 8 dB variation over 24 hours & 6 months [76.605(a)(4)]. • < 3 dB of variation between adjacent channels [76.605(a)(4)]. • < 12 dB of difference between any 2 channels in a 500 MHz system and 1 dB allotted for each 100 MHz above 500 MHz. This is tilt and peak-tovalley [76.605(a)(4)]. • A maximum level is stated that doesn’t overload the subscriber’s receiver [76.
Application Notes: Proofing and Testing Sweepless mode if using a function generator. Connect the Tx or function generator to the Video In port on the modulator that you are going to test. Next, connect your field unit to the modulator output and press the SWEEP button. Once you have adjusted your Start and Stop frequencies to match the particular channel plan, you will see the response of the channel under test. Press the “func” and “6” key to store this trace as a Sweep Reference.
Application Notes: Proofing and Testing range of the field unit is 52 dB. The FCC specification is for CNR > 43 dB. Most systems design for ~ 48 dB CNR at the end-of-line to account for house amps, bigger TV screens, and to allow some headroom for digital loading affects. Use a bandpass filter and lab amp otherwise, or when doing CSO and CTB. The FCC specifies that these coherent distortions should be > 51 dBc (below the reference carrier) for NCTA and > 47 for HRC systems.
Application Notes: Proofing and Testing NOTE: Measuring digital "haystacks" with a spectrum analyzer is very misleading. The level reading is based on the RBW of the analyzer and there are correction factors associated with this. A simple calculation is not adequate because of the shape of the "haystack." Refer to the "Digital vs. High Speed Data" article that was published in Communications Technology’s Dec. ’98 issue. Measure levels of both channels and calculate the difference. This is the S/ N.
Application Notes: Proofing and Testing Terminal Isolation [76.605(a)(9)] Terminal isolation shall be at least 18 dB. In reality, it’s usually much better than this. Depending on the source of the purchase! Ground Loops & Voltage Potential Differences Use a device called a 188A to test for dangerous voltage potentials before touching anything. You could also use a voltmeter in the ammeter mode. Connect one lead to the cable sheath/connector and another lead to a known good ground.
Application Notes: Proofing and Testing by power pack filter failure, bad solder connections, corroded connectors, impulse noise, etc. Diagnosis for 1 or 2 bars slowly scrolling up on the TV is as follows: If it’s one hum bar (50/60 Hz), check for bad connections where voltage is ac. If it’s 2 hum bars (100/120 Hz), check the dc power pack for proper ac input, check for power-pack ripple (possible filter cap or diode failure).
Application Notes: Proofing and Testing dipole". Leaks in excess of these strengths at respective distance and frequency must be repaired in a timely manner.
Appendix B Specifications Frequency Range: 5 to 1,000 MHz Accuracy: ±10 ppm at 25°C; ± 10 ppm drift over temp.; ± 3 ppm/year aging Resolution bandwidths: 30, 280 kHz and 2MHz (30 kHz for CTB/CSO only) Tuning resolutions: 10 kHz Sweep resolution: 250 kHz maximum Level Measurement Range: -40 to +60 dBmV Resolution: 0.1 dB Accuracy: ±1.0 dB from -20 to +50°C Log linearity: ±0.5 dB Flatness: ±0.
Specifications Uncertainty for digital carrier: Additional ±0.5 dB (digital types 16/32/64/256 QAM, QPR, QPSK, VSB, CAP-16, DVB/ ACTS and TDMA using zero-span spectrum mode) @ 280 kHz RBW Carrier-to-Noise In-service measurement. Non-scrambled channels only. No preselection required for 78 channels or less. Best dynamic range at +10dBmV or higher input. Range: ≥ 52 dB Resolution: < 0.5 dB Hum Measurement In-service measurement. Carrier > 0 dBmV. Non-scrambled channels only.
Specifications Sweep Mode (Forward sweep not available on SDA-5510) Frequency range: 5-1000 MHz Display span: user definable Display scale/range: 6 vertical divisions 1, 2, 5, or 10dB/ division Sweep pulse occupied bandwidth: 30 kHz Stability: +/- 0.
Specifications Zero-Span Mode Video BW: >1MHz, 100 kHz, 10 kHz, 100 Hz Resolution BW: 2 MHz, 280 kHz, 30 kHz Measurement BW compensation: programmable 1 kHz - 99 MHz Pulse measurement accuracy: Sweep times: nominal level in 10 µs +/- 2 dB from nominal in 5 µs (>1 MHz VBW, 280 kHz RBW) 100 µs to 20 s (1, 2, 5 settings) Intermodulation Distortion (CSO/CTB) Range: ≥ 60 dB Resolution: 0.
Specifications Data Storage Files stored: Autotests, tilt, channel plans, scan, and forward sweep. Also reverse sweep and reverse amp alignment. Spectrum mode (regular with max hold and CSO/CTB). Zero-span. Allocated on demand. Storage capability: Simultaneous- more of one file Reference Storage type can be "traded" for less of another. All files stored as database, not as screen picture.
Specifications AC line (SDA 5000) Charger input: 100-250 VAC 50 - 60 Hz, 0.
Specifications MER (Modulation Error Ratio): 64 QAM / Option 4A: Accuracy: 22-35 dB ±2.0 dB (typical, see chart below) 64 QAM / Option 4B: Accuracy: 21-35 dB ±1.5 dB 256 QAM / Option 4A: Accuracy: 28-35 dB ±2.0 dB (typical, see chart below) 256 QAM / Option 4B: Accuracy: 28-35 dB ±1.5 dB MER Accuracy Worse Case Condition, QAM 64, Annex A, 6.
Specifications EVM (Error Vector Magnitude): 64 QAM / Option 4A: Accuracy: 1.2% - 5.2% ± 0.5% (1.2% - 2.0%) ± 1.0% (2.1% - 4.0%) ± 1.4% (4.1% - 5.2%) 64 QAM / Option 4B: Accuracy: 1.2% - 5.8% ± 0.5% (1.2% - 2.5%) ± 1.1% (2.6% - 5.8%) 256 QAM / Option 4A: Accuracy: 1.1% - 2.5% ± 0.6% 256 QAM / Option 4B: Accuracy: 1.1% - 2.5% ± 0.
Specifications Power Source: Battery: Extended life nickel metal hydride 12V / 3.5A-hr Charge time: ~4 hours Operating Time: 2.5 hours continuous use (typical) in QAM View mode Universal AC Charger/Adapter: Input: 100-250 VAC, 50-60 Hz, 0.
Specifications B 352
Appendix C Status Indicators and Icons Status Indicators The following status indicators are displayed in the title bar: Unlocked Low Battery Function Key Pressed Alpha Entry Mode Numeric Entry Mode Arrow Key Selection Mode Backlight On (Manual Operation) Backlight On (Auto Operation)
Status Indicators and Icons Video Carrier Audio Carrier Single Carrier DUAL Carrier Band Pass Filter (Hum screen) Low Pass Filter (Hum screen) Noise (C/N screen) Soft Key Icons C Amplifier / Low Pass Filter Submenu Sweep Enable Video Enable Offset Submenu Level Submenu Bandwidth Submenu Noise Scan Enable Limit Check Submenu Frequency Submenu 354
Status Indicators and Icons Enable / Disable Start Zero Span Check Limits A or B Marker Toggle Maximum Hold Start CSO/CTB Test Reference Level Select High Tilt Pilot Channel Tilt Compensation Submenu Select Low Tilt Pilot Channel Hysteresis Autoscale Video Bandwidth Scan Time Resolution Bandwidth Restart Maximum Hold C 355
Status Indicators and Icons C Measurement Bandwidth Demodulation Toggle Scale Volume Up Return to Last Mode Volume Down Audio Enable Cancel Restart Center Frequency 60 Hz Filter Enable / Disable Desired / Undesired Marker Toggle 120 Hz Filter Enable / Disable Low Pass Filter Enable Log / Linear Toggle Pre-Amp Enable 356
Status Indicators and Icons <1 KHz Filter Enable Marker to Peak Dwell Span Save this Channel BW Stop Frequency Save BW to All Channels Start Frequency Trigger On/Off Manual Trigger Additional Option-Specific Icons SDA Option 2 -- Portable Sweep Transmitter This option uses icons already listed above.
Status Indicators and Icons View Node List Toggle Node SDA Option 4 -- QAM In addition to many of the icons listed above, Option 4 uses the following icons: Edit Modulation Format Edit Symbol Rate Display Digital Detail Zoom Submenu Zoom-In One Level Zoom-Out One Level Zoom-Out to Largest View Frequency Response Screen Group Delay Screen QAM Level C 358
Appendix D User and Error Messages Introduction The SDA is equipped with helpful messages that may appear to indicate improper operation or unit malfunction. This appendix provides an explanation of the condition causing a message to appear and the suggested response. ERROR... No STEALTH telemetry! Condition: No telemetry established between Transmitter and Receiver Response: Check connection and ensure telemetry frequencies are matched. SORRY...
User and Error Messages ERROR... The noise frequency is out of range! Condition: The noise offset frequency plus the carrier frequency exceeds the range of the unit. Response: Choose a smaller noise offset frequency value. ERROR... Insufficient signal level to perform the measurement! Condition: A minimum carrier level is required for C/N and HUM measurements. Response: Choose another channel or frequency with greater than the minimum level. SORRY... This is an illegal name and cannot be used.
User and Error Messages SORRY... Not enough sweeps have occurred to store an accurate reference. Please allow more time in SWEEP. Condition: An attempt to store a reference without sufficient sweeps. Response: Allow more time in Sweep Mode. ERROR... A system error has occurred! Condition: A system error has been detected. Response: Restart the unit and try again. ERROR... There is no Response: from the printer! Condition: The printer is not responding to the unit.
User and Error Messages ERROR... A system error has occurred! Please select another mode. Condition: A system error has been detected. Response: Select another measurement mode or restart the unit and try again. ERROR... At least two tilt channels must be programmed and enabled! Please select another mode. Condition: Tilt mode is selected with less than two tilt channels programmed. Response: Edit channel plan to program at least two tilt channels. WARNING... The selected plan will be deleted.
User and Error Messages SORRY... This cannot be completed due to a system error. Condition: A system error was detected. Response: Restart the unit and try again. WARNING... This channel will be deleted! Condition: A channel is about to be deleted. Response: Press OK to delete, STOP to cancel. SORRY... The last channel cannot be deleted! Condition: An attempt was made to delete the last channel of a plan. Response: A channel plan must contain at least one channel. If desired, delete the entire plan.
User and Error Messages ERROR... Hum cannot be measured on a scrambled channel! Condition: A channel that has been programmed as scrambled in setup has been selected in Hum mode. Response: Select a channel that is not scrambled. Hum measurements are not possible on a scrambled channel. SORRY... No more tilt channels can be programmed. Condition: The maximum number of tilt channels has been reached.
Appendix E Glossary This glossary covers terminology used in the manual, as well as other terms, that will help to clarify discussion and procedures in the manual. Sources include Acterna proprietary documents; the Jones Dictionary for Cable Television and Information Infrastructure, 4th Edition; and the IEEE Standard Dictionary of Electrical and Electronic Terms, 4th Edition, and other electronics authorities.
Glossary lowest frequencies carried by a channel. Also the speed (bit-rate velocity at which data can be transferred and presented. E C/N; also CNR Carrier-to-Noise ratio, normally expressed in dB: the ratio of peak carrier power to root mean square (RMS) noise power (noise floor at video bandwidth) adjacent to the carrier. ½ See Noise Offset. CATV Community Antenna Television, commonly used to refer to Cable Television.
Glossary Edit Box On many LCD screens you are required to make changes, or have the option of making changes to system parameters. In these instances the Edit box appears as the last line of the LCD screen. It also carries instructions, when appropriate. such as “Press ENTER….” Equalization Reducing distortion of frequency and/or phase by compensating for attenuation and/or time-delay at frequencies within the transmission band.
Glossary Level Level is a measurement of signal and reference voltages in the cable system, expressed in dBmV or as a ratio expressed in dB E LPF Low Pass Filter Modem Modem” is a contraction of Modulator-Demodulator. A Modem converts computer digital signals to analogue for data transmission, or demodulates upon receipt, for use within a computer.
Glossary Pilot Channel The Lowest and Highest of the channels (9 max total) selected as criteria for TILT. E Pilot Level Level in dBmV of Pilot Channel used for TILT. Pixel A Pixel (Picture Element) is the smallest area of a television picture capable of being delineated by a signal passing through the system. PSK Phase-Shift Keying modulation: shifting the carrier frequency plus or minus 90- degrees in phase to represent “0” and “1”, respectively, for digital transmissions.
Glossary E Suck-Out Excessive cable transmission loss that affects or several channels acutely as a function of frequency due to sharp kinks or bends, or to minor imperfections regularly spaced in the line. Sweeping Injecting into the cable and transmitting downstream in a CATV system at selected points in the spectrum a series of output signals that vary in frequency between preset or adjustable limits, at a rate that is also adjustable.
Index Symbols and Numbers 13 dB amplifier, enabling (Spectrum Analyzer mode) 135 16 QAM modulation 104 24-hour reports (Autotests) 192-193, 261-265 reading 193 24-hour tests, FCC regulations 335-336 256 QAM, modulation 313 50 MHz low-pass filter, enabling (Spectrum Analyzer mode) 135 A absolute carrier levels 15 advanced services, reverse path troubleshooting 96-98 AGC (Automatic Gain Control) 115 alignment reverse amplifiers 303-304 reverse sweep 7 alignment mode 19 alpha entry mode 221 alphanumeric keys
Index results file names 188 saving locations 185 selecting probe points 186 temperature 190 test point compensation 188 test types 189 voltage measurements 187 headend units 252-259 measurements, failure indicator 192 performing tests 184-191 results 24-hour reports 192-193, 261-262 displaying 191 displaying intervals 194-195, 264265 interval information 192 location information 192 printing 191 reading 193 test locations creating/editing 182-184 deleting locations 183 location types 180-181 new locations
Index editing SDA-5500 283 editing, SDA-5500 277-283 files, storing 198 Inverted Spectrum 50 Stealthware 53 parameters 38-57 editing 46-49 reference files 203 remote, copying 56 reverse sweep creating 291-294 editing 294-295 headend units 290-295 selecting 294 setup, headend units 227 softkey QAM channel 52-53 tilt compensation 312 video signal type 39 Channel Tuning Sequence 40 Channel Tuning Sequence option 277 Channel Type option 278 channels audio levels 15 deleting, unused 53 overlapping 368 pilot chan
Index D D/U (Desired/Undesired) 366 date format 24 Date Format option 223 Date option 224 dBc values 161 DC-12 307, 318 decibels with respect to the carrier levels 161 decision boundaries, constellation display 166 Default to Factory Settings option 224 Delete Unused Channels option 280 deleting channels, unused 53 sweep reference files 202 depth of modulation 366 Desired/Undesired (D/U) 366 Detail display 155-157 diagnostics configuration 29 Diagnostics mode 25 Diagnostics option 224 diamond keys 220 digit
Index Error Vector Magnitude (EVM) 27, 154 errors, Autotests 263 external losses, test points 62 F factory settings, defaulting to 29 fast scan rate 116 fast scanning, reverse path troubleshooting 99 FCC 24-hour tests 335-336 audio/video tests 335 carrier to noise ratio readings 337-339 egress limits 333 headend proofing 341 hum measurements 340-341 in-channel response measurements 240 in-channel sweeping 336-337 leakage measurements 341-342 proofing and testing regulations 335-342 record keeping regulatio
Index parameters 47 Sweep key 15 telemetry frequency 370 transmitter 31 tuning step sizes 26 frequency adjustments Scan mode 233 Spectrum Analyzer mode 240 Sweep mode 246 Frequency Modulation (FM) 367 Frequency option 279 frequency response identification 315 Frequency screen, forward SWEEP 77 Frequency Submenu icon 88 frequency tuning QAM 52 QAM measurement mode 52 Frequency Tuning Step Size option 226 Function keys QAM 14 screen contrast 11 fundamental hum frequency 26 Fundamental Hum Frequency option 226
Index hum modulation 15 Hybrid Fiber Coax.
Index Scan mode 234 Lines/Page option 224 Local measurement trace 142 Loopback sweep 19, 93-94 Low Pass Filter State, C/N measurement 123 low pass filters, CPD analysis 101 M maintenance 207-209 Maximum Hold Function, QAM Ingress 165 Measurement Bandwidth (MHz) 48 Measurement Bandwidth Adjustments option 279 Measurement Bandwidth, C/N measurement 123 measurement files printing 200, 248 viewing 200, 248 measurement hold, PathTrak mode 147 Measurement menu 116 measurement mode keys 13-14 Measurement mode, di
Index Node List option 142 nodes 368 noise accumulation, forward path 96 headend 7 impulse, troubleshooting 333 reverse broadcast 304-305 reverse noise 68 reverse path troubleshooting 96-97 segmented 327 Spectrum Analyzer mode, cautions 331 troubleshooting 331-332 Noise Enable 88 noise offset 368 Noise Offset (MHz) 48 noise offset frequency adjustments C/N mode 236 Noise Offset Frequency Adjustments option 279 noise trace 88 normal scan rate 116 NTSC (National Television System Committee) 368 numeric entry
Index probe points (Autotests), selecting 186 proofing and testing, FCC regulations 335-342 proof-of-performance tests 19-20 proof-of-performance, automatic tests 179 PSK (Phase-Shift Keying) modulation 369 Pulse Amplitude Modulation (PAM) 368 pulse modulation 104 Q QAM (Quadrature Amplitude Modulation) 52, 149, 155, 158, 369 channel plans softkey 52-53 digital stream 46 channel, configuration 51-52 Function keys 14 Ingress Mode 160-166 modulation 49 modulation format 155 signal lock errors 151 symbol rate
Index SDA-5510 284-290, 291 dual cable networks 73 efficiency considerations 327-329 field unit settings 320 headend considerations 321 increasing speed 327 ingress, preventing 324 insertion level 69 levels 72-74 procedure 321-324 SDA-5500 285-288 SDA-5510 285-288 procedures 324 references 322 resistive test points 62 setup headend units 318 SDA-5500 288-290 SDA-5510 288-290 split band networks 72 transmitter, testing 295-296 wiring 72-74 wiring connections SDA-5500 285, 287 SDA-5510 285, 287 Reverse Sweep
Index PathTrak Field View 141 signal level considerations 71 test points, connecting to 70 troubleshooting, reverse path 95 SDA-5500 alphanumeric keys 220-221 C/N mode 219 CDP analysis 101 channel plan setup 227 channel plans creating 274-283 editing 277-283 configuration forward sweep 267-284 general 222-228 reverse sweep 284-290, 291 features 5-6 Hum mode 219 Level mode 219 measurement mode keys 218-220 measurements setup 225-227 Mod mode 219 modes, basic operation 228-246 printing, measurement mode scree
Index spectrum analyzer display 15 Spectrum Analyzer mode 131 Amplifier submenu 135 Amplifier/Low-Pass Filter submenu 137 Bandwidth submenu 137, 139 files 198 Frequency submenu 134-135 headend units 239-243 Level submenu 134, 138 noise level readings, cautions 331 SDA-5500 220 SDA-5510 220 setting dwell time 135 spectrum range 133 Timebase submenu 138 Zero Span 131 Zero Span submenu 136 spectrum range 133 Spectrum screen 131-133 spikes 325 troubleshooting 313 split band networks reverse sweep 72 wiring conn
Index SDA-5510 219 Sweep References 302-303 Sweep References menu 202 sweep speeds 49 Sweep telemetry 31 Sweep Telemetry On/Off option 225 Sweep Transceiver setup headend units 227 Sweepless Mode 370 Sweepless Sweep 19 Sweepless sweeps 92-93 Symbol Rate 49 symbol rate Constellation 171 QAM Ingress 163-164 Symbol Rate, digital analysis 159 digital analysis, symbol rate 155 symbol rates, QAM 169 system information 32 T tabs Nav support key 10 Navigator Interface 11 TASO (Television Allocation Study Organizat
Index time 24 Time Division Multiple Access, see TDMA Time option 223 time-out period 23 title bar 370 transmission loss, coaxial cable 112 transmitter calibration 31 forward sweep, testing 283-284 frequency 31 reverse sweep, testing 295-296 Transmitter Attenuator option 225 Transmitter Diagnostics option 225 Transmitter Frequency option 225 Transmitter On/Off option 225 troubleshooting bad response 314, 326 CPD 329-330 forward sweep 314-315 impulse noise 333 ingress, identifying source 332 ingress/egress,
Index 386
