NP88 Encoreâ PRO Encoreâ NP88 FLXä SERVICE MANUAL NP88 FLEX
NP88 FLEX Foreword Foreword Unication maintains a worldwide organization that is dedicated to provide responsive, full-service customer support. Unication products are serviced by an international network of company-operated product care centers as well as authorized independent service firms. Available on a contract basis, Unication's comprehensive maintenance and installation programs enable customers to meet requirements for reliable, continuous communications.
Foreword NP88 FLEX Computer Software Copyrights The Unication products described in this manual may include copyrighted Unication computer programs stored in semiconductor memories or other media. Laws in the United States and other countries preserve for Unicationcertain exclusive rights for copyrighted computer programs, including the exclusive right to copy or reproduce in any form the copyrighted computer program.
GENERAL
NP88 FLEX GENERAL Contents Contents About This Publication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-1 Audience . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1 Finding Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
NP88 FLEX GENERAL About This Publication About This Publication Using this manual and the many suggestions contained in it assures proper installation, operation, and maintenance of Unication products and equipment. Refer any questions about this manual to the nearest Customer Service Manager. Audience This Service Manual is provided to assist service personnel in the test and repair of Unication NP88 FLEX .
GENERAL NP88 FLEX About This Publication E Warning: Emphasizes information about actions which may result in personal injury. Revisions Any changes that occur after manuals are printed are described in Publication Revision bulletins.
NP88 FLEX GENERAL Specifications Specifications Paging Sensitivity: Refer to specific receiver information. Spurious & Image Refer to specific receiver information. Rejection: Frequency Stability: Refer to specific receiver information. EIA Selectivity: Refer to specific receiver information. Alert Tone Frequency: 2731 Hz standard alert with user selectable alerts Alert Tone Duration: 8 ± 0.
GENERAL NP88 FLEX Product Overview Product Overview The Unication NP88 FLEX pagers are miniature, microcomputer-controlled FM receivers that operate in the high-band 900 MHz range (929-932 MHz). Each pager has a 12-digit numeric display and is powered by a single AAA-size battery. These pagers use FLEX paging format. Refer to the applicable Receiver section in this manual for information about which format is used with each frequency range.
NP88 FLEX GENERAL Product Overview G uide listed in "R elated P ublications" for mor e infor mation about pr ogr ammable options. A ddres s ing E ach pager has memor y which can be pr ogr ammed for either one or two addr esses. T he memor y can be pr ogr ammed by using the appr opr iate P ager P r ogr amming S oftwar e and P ager M echanical I nter face. C ontrols and Indic ator T he pager contr ols ar e the thr ee buttons located on the fr ont of the pager (r efer to F igur e 1-1).
GENERAL NP88 FLEX Product Overview When a battery is first inserted into the pager, the pager powers up in the OFF state. In this cold start condition, the On/Read/Select button has priority over the Menu button, and the Menu button has priority over the Backlight button, respectively, if more than one button is pressed simultaneously. Menu Button The button is used to display and scroll through the menu. The button is also pressed to increment the digits when setting the time or an alarm.
NP88 FLEX GENERAL Product Overview The pager indicators (also known as icons) are listed in Table 1-1. Table 1-1. Indicators Icon D Meaning Description Alert Tone Enabled Incoming messages are indicated by an alert tone. Message Protected The displayed message is “locked” and protected from deletion. [ Silent Alert Enabled Incoming messages cause the pager to vibrate. An alert tone is not given. B Continued Message The message is continued on the next screen.
GENERAL NP88 FLEX Product Overview Table 1-2. Menu Prompts (Continued) Prompt Response pager off ? Press set alert ? Press to display selected alert type. Press to sample alert types. Press again to select an alert type and return to the Status screen. set alarm ? Press to select on/off sequence. on or off flashes. Press to turn alarm on or off. Press to select the hour. Press to change the hour. Press to select minutes. Press to change the first digit of minutes. Press .
NP88 FLEX GENERAL Product Overview VIBRA-Page® Operation VIBRA-Page is a standard feature in NP88 FLEX pagers. The pager is equipped with a miniature motor causing the pager to vibrate when a message is received in the silent mode. Pagers operating in the silent mode do not produce a tone alert. Instead, when a page is received, only the vibrator and the alert lamp activate. The silent mode permits the pager to receive a paging call while inhibiting the tone alerting circuit.
GENERAL NP88 FLEX Product Overview Confirmation Alert When switched from tone-only to silent mode, the pager vibrates for a short period of time to confirm the pager is in the silent mode. When switched from silent to tone-only mode, a short beep is emitted to confirm the switch to tone-only. Page Alert/Unread Message Indicator When a message is received, the pager emits an alert (either tone or vibrate) and displays an unread message indication (i.e., 1 page, 2 pages, etc.).
NP88 FLEX GENERAL Product Overview Selective Message Erase The user can delete the message currently displayed. A single unprotected message is erased by pressing the Menu ( ) button while any portion of the message is displayed. If the user clears a message, all of the remaining messages are renumbered starting at slot 1. Battery Saver FLEX pagers use the advanced battery saving features of the FLEX paging protocol. The pager can be programmed to check for pages at intervals ranging from 1.
GENERAL NP88 FLEX Product Overview Automatic Reset The eight-second paging alerts automatically stop unless manually reset (halted) by pressing any one of the buttons before the alert ends. All alerts are changed to two-second alerts during the lo cell condition. Standard Options Battery NP88 FLEX pagers are designed to operate with a single AAA-size alkaline battery. N To ensure proper memory retention, turn the pager off before removing the battery.
NP88 FLEX GENERAL Product Overview Date Format The date can be shown in the U.S. style with the month followed by the day or in the European style with the day followed by the month. Alert Options Audible Low Battery Alert If the pager senses a low battery voltage, this option provides a low battery audio alert with a two second warble tone indicating the battery needs to be changed. Page Alert Duration This option allows you to select the alert time of 2 seconds, 8 seconds, or 16 seconds in length.
GENERAL NP88 FLEX Product Overview specific options that are available for group call, and the corresponding addresses that are active for that option or each option. Table 1-3.
NP88 FLEX GENERAL Product Overview FLEX-Specific Options Group Call/Independent Second Address The group call option allows multiple pagers to be alerted at the same time by using the second FLEX address programmed as a Group address. The individual is contacted in one of two ways: individually or as part of a group. Refer to Table 1-4 for a list of the options and the address combinations. Table 1-4.
GENERAL NP88 FLEX Product Overview Automatic Message Formatting This system-driven feature allows the user to view a 10 character numeric message formatted with hyphens. Upon receipt of a formatted message, the pager automatically inserts hyphens following the area code and the exchange. Automatic Reset The paging alerts automatically stop unless manually reset (halted) by pressing any one of the buttons before the alert ends.
NP88 FLEX GENERAL Theory of Operation Theory of Operation The NP88 FLEX pagers consists of a radio frequency (RF) receiver section and a microcomputer-controlled decoder section. A message is received via an RF carrier that is frequency modulated by a coded binary sequence utilizing FLEX paging protocol. The circuitry in the receiver performs the RF to intermediate frequency (IF) conversion.
GENERAL NP88 FLEX Theory of Operation General Circuit Description The following information describes the general theory of operation for the 352 pager. Refer to Figure 1-5 for a functional block diagram. Figure 1-5. Functional Block Diagram Power Operating power for both the receiver and the decoder boards is obtained from the battery. On the receiver board, a 1-volt regulator supplies the RF circuitry with power. The regulator is turned on and off by the decoder via the control lines.
NP88 FLEX GENERAL Theory of Operation Receiver The antenna receives the modulated RF paging signal and couples it to the amplifier/preselector to amplify and filter the RF signal. The mixer converts the RF signal to an intermediate frequency (IF). The crystal filter attenuates the signal above and below the RF carrier. The oscillator/multiplier supplies the appropriate injection signal to convert the RF paging signal to the correct IF.
GENERAL NP88 FLEX Paging Coding Schemes Paging Coding Schemes FLEX Paging Format, Code, and Code Capacity A FLEX transmission cycle is 4 minutes long and divided into 128 frames, numbered from 0 to 127. Fifteen FLEX cycles (numbered 0 through 14) occur in one hour. A single FLEX frame is transmitted at 1.875 seconds per frame (32 frames per minute) and consists of 1 sync block followed by 11 frame blocks (numbered 0 through 10). The structure of a FLEX frame is shown in Figure 1-8.
NP88 FLEX GENERAL Paging Coding Schemes Eleven message blocks containing interleaved data follow the sync block. Data is interleaved within the message blocks to provide signal fading protection for up to 10 msec. The message blocks contain frame and system information, addresses, vector and original data. Each address has an associated vector which specifies the message type and points to the beginning of the message data. The FLEX code provides five billion address combinations.
GENERAL NP88 FLEX Maintenance Maintenance G This product contains static-sensitive devices. Use anti-static handling procedures to prevent electrostatic discharge and component damage. Removing/Replacing the Battery 1. 2. Locate the ribbed battery door lock on the side of the pager. To unlock the battery door, slide the lock away from the battery door. Press on the indented, ribbed area of the battery door and slide the door in the direction indicated by the arrowhead as shown in Figure 1-9.
NP88 FLEX GENERAL Maintenance Figure 1- 10. Removing the Back Cover When performing the following step, ensurethe pager is not damaged when inserting the disassembly tool into the exposed battery end. Do not push the disassembly tool all the way inside of the pager. 1. 2. Hold the pager with t he back cover facing up .
GENERAL NP88 FLEX Maintenance 3. Twist the disassembly tool counterclockwise while lifting it up toward the back housing.. The latch should begin to unsnap . Separate the front and back housin g by liftin g the back housing up and away from t he front housing as shown in Figure 1-12. The back housing lip at t he LCD end will separate last. 4. Figure 1-12. Replacing the Back Cover 1. 2. 3. 4. 5. 6. 7.
NP88 FLEX GENERAL Maintenance Figure 1-13. Removing the Front Cover 1. 2. Remove the battery, battery cover, and back cover according to the earlier procedure. Hold the front housing down, pull the innerunit to the LCD end and lift it from front housing as shown in Figure 1-14. Figure 1-14.
GENERAL NP88 FLEX Maintenance Removing the Receiver Board 1. 2. Removing the battery, battery cover, and back and front cover according to the earlier procedures. Hold the decoder board down, grasp the receiver board and gently lift the receiver board away from the decoder board as shown in Figure 1-15. F igur e 1-15. R eplac ing the R ec eiver B oard 1. 2. 3. 1-26 Align the interconnect plug on the decoder board with the socket on the receiver board.
NP88 FLEX GENERAL Maintenance Removing the Light Guide and Snubber Pad 1. 2. Remove the battery, battery cover , back and front cover , and r eceiver boar d as described in the ear lier pr ocedur es. R emove the light guide as shown in Figur e 1-16. F igur e 1-16. 3. 4. Remove the snuvver pad as shown in Figure 1-17. The left is decoder board. F igur e 1-17.
GENERAL NP88 FLEX Troubleshooting Troubleshooting NP88 FLEX pagers combine leadless-component technology with a unique miniature design to provide a unit that lends itself well to serviceability. The pager’s circuitry is contained in two individual sections. One section is the receiver circuit board, and the other is the decoder circuit board. To disassemble the pager and remove the major assemblies, refer to the Maintenance procedures.
NP88 FLEX GENERAL Troubleshooting Self-Diagnostic Feature FLEX Pagers 1. With the pager in the OFF mode, press the button eight (8) times within 3 seconds to enter the Tuning Test mode and disable the battery saver. The LCD displays: -----------1 Figure 1-28. 2. To exit the test mode, press the the pager is on. button.
GENERAL NP88 FLEX Troubleshooting distortion), and timing of pulses. The input and output oscilloscope check easily isolates a defective IC. Circuit voltages are given in various key places on the schematic diagrams as an aid to the isolation process. Give particular attention to the dc voltages at the input and output pins of the circuit and its decoupling circuits. A low voltage, or a higher than normal voltage at the input or output should be investigated further before replacing the circuit.
NP88 FLEX GENERAL Troubleshooting START TURN POWER ON. NO BATTERY ALERT OK ? MEASURE BATTERY VOLTAGE. YES BATTERY VOLTAGE OK ? NO REPLACE BATTERY. YES REGULATOR VOLTAGE OK? NO REPAIR. YES PERFORM SENSITIVITY CHECKS ALIGNMENT OK? NO REALIGN OR REPAIR. YES PERFORM PAGER DECODING CHECKS. DECODES PROPERLY ? NO REPAIR. YES TURN POWER OFF. STOP Figure 1-29.
GENERAL NP88 FLEX Troubleshooting Paging Sensitivity Check N Paging sensitivity tests must be performed in a screen booth with a minimum of 80 dB attenuation. Pagers, especially FLEX pagers, lock onto the first identifiable signal regardless of the source. If a pager under test locks onto a signal from a source other than the signal generator it will not respond to the paging code from the encoder. Ensure the pager is not turned on until it is secured within the booth.
NP88 FLEX GENERAL Troubleshooting 9. Using the test encoder, initiate the paging code. The pager emits an interrupted alert tone each time the paging code is initiated. 10. Reduce the RF signal level from the FM signal generator to the lowest level that produces an alert tone on three successive tries. This level must be less than the level specified in the applicable receiver section.
GENERAL NP88 FLEX Troubleshooting ACPB-930353-A Figure 1-31. 10 dB Rise Measurement Circuit Checks Refer to the applicable receiver section in this publication for identification of the components and test points referenced in the following sections. Oscillator Warp Range The oscillator warp range is the difference between the highest and lowest IF frequencies obtained while varying the Oscillator Trimmer Capacitor. 1. Ensure a battery with a minimum output of 1.3 volts is installed in the pager. 2.
NP88 FLEX GENERAL Troubleshooting 3. 4. 5. 6. Refer to the applicable schematic waveform and voltage information in the appropriate supplement. Ensure the pager is in self-diagnostic mode 5 (refer to "Self-Diagnostic Feature"). Turn off the RF output of the signal generator. Monitor the collector of the First Mixer Transistor and note the maximum and minimum dc voltage levels as the oscillator is enabled and disabled.
GENERAL NP88 FLEX Troubleshooting 4. 5. 6. 7. Ensure the pager is in self-diagnostic mode 5 (refer to "Self-Diagnostic Feature"). Install the alignment back cover on the pager. Place the unit in the RTL-1005 Radiation Test Fixture, modified with the RPX4687 Nest and Contact Flip-down Assembly. Measure the ac voltage at M1 with no RF signal applied. The noise level reading must be between -48 dBm and -65 dBm for a properly aligned/tuned receiver.
NP88 FLEX GENERAL Troubleshooting 8. Check the RF takeover: a. Apply 1.3 Vdc to the battery contacts. b. Monitor M1 with ac voltmeter. c. Tune pager according to “Alignment Procedure” in the applicable receiver section. d. Turn the RF signal generator off and note the noise level at M1. e. Short the base of the RF Amplifier to ground and note the level drop. With a properly functioning RF amplifier, the noise drops 5 to 9 dB, which indicates the proper amount of gain in the stage.
GENERAL NP88 FLEX Troubleshooting • If the bandwidth is still outside the prescribed limits, replace the IF Crystal Filter. • If the bandwidth is within the prescribed limits, replace the Ceramic IF Filter (Discovery I receivers). • If testing a Discovery II receiver or if the bandwidth is still outside the prescribed limits, replace the Backend Demodulation IC on the receiver circuit board. 11. Check data filter cutoff frequency: a.
NP88 FLEX GENERAL Troubleshooting a. If yes, the backend is properly aligned; no further action is needed. b. If no, realign the backend. 11. Replace and realign the Backend Demodulator IC if the problem persists.
DECODER
NP88 FLEX DECODER Contents Contents Model Numbers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-1 Related Publications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1 Operating Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
NP88 FLEX DECODER Model Numbers Model Numbers Refer to the applicable receiver section for a list of model numbers, their descriptions, and contents. Related Publications Decoder Supplement - NYN4858, NYN6473, NYN6665 6881104B18 Decoder Supplement -NYN4063 6881015B81 Refer to the GENERAL section and applicable receiver section of this manual for additional publications.
DECODER NP88 FLEX Operating Modes Operating Modes There are three basic modes of operation of the NP88 FLEX decoder: power-up, page search and page alert/display. Power-up Mode NP88 FLEX decoder operates in one of two power-up modes, depending on the condition (at or below minimum voltage or good) of the primary battery. If the primary battery is not present, the pager does not power up.
NP88 FLEX DECODER Operating Modes Data-decoding Interval - FLEX Pager When the pager powers up, the receiver is turned on, and the decoder begins to search for a valid FLEX frame. When a valid FLEX frame is detected, the pager performs the following sequence of operations: a. synchronizes to the channel b. searches for the pager’s FLEX address c. begins to operate at the desired collapse value d.
DECODER NP88 FLEX Circuit Description Circuit Description The decoder section consists of five functional blocks: • Power Circuits • Support Module • Microcomputer (µC) • LCD • Alert Circuits Refer to “ Theory of Operation” in the GENERAL section for a functional block diagram. Power The negative side of the battery is connected to circuit common. The positive voltage from the battery is applied to the Support Module where it is converted to 3 V operating voltage.
NP88 FLEX DECODER Circuit Description The µC controls all major functions of the decoder, including processing of receiver data passing through the Support Module and user interface functions via the alert circuits and LCD. The µC module consists of: • Read-Only-Memory (ROM) to store the executable program code. • Random Access Memory (RAM) to store all user messages and other key processing data. • A display driver to control the LCD.
DECODER NP88 FLEX Troubleshooting Troubleshooting If the pager failed the paging sensitivity check but passed the 10 dB rise measurement, and the receiver circuits have the required data output level, the fault is probably in the decoder circuits. The following table (Table 2-1) provides a quick, preliminary check of possible problem areas.
NP88 FLEX DECODER Troubleshooting FLEX Pagers No Power-Up 1. 2. Ensure battery contacts are good. Check Support Module pin 40 for a high to ensure the Support Module is not resetting the £gC. NO POWER-UP FAIL BATTERY VOLTAGE REPLACE BATTERY FAIL OK VOLTAGE AT SUPPORT MODULE U5Pin3 ≥1.
DECODER NP88 FLEX Troubleshooting No Display or Bad Display on Power-Up Check the solder connection between the circuit board and the Heat Seal Connector of the LCD. NO DISPLAY ON POWER-UP CHECK SUPPORT MODULE U5 PIN 2 OR TSP3 FOR 3V FAIL REPLACE SUPPORT MODULE OK CHECK SIGNALS AT µC PINS 24-27,2 24-27,29-52 FAIL REPLACE µC OK REPLACE HEAT SEAL CONNECTOR/LCD ASSEMBLY Figure 2-8.
NP88 FLEX DECODER Troubleshooting No Audible Alert Ensure the following before initiating this troubleshooting procedure: a. Verify the pager is in the audio mode and not in the silent alert mode (check for the speaker icon). b. Check the options set with the Pager Programming Software to ensure the “Completely Silent” pager option is not set. c. Verify the transducer contacts are okay.
DECODER NP88 FLEX Troubleshooting No Vibrator Alert Ensure the following before initiating this troubleshooting procedure: a. Verify the pager is in silent mode. b. Check the options set with the Pager Programming Software to ensure vibrator alerts are enabled and the “Completely Silent” pager option is not set. c. Verify that there is no flux or other residue on either the circuit board or vibrator contacts. NO VIBRATOR ALERT APPLY 1.
NP88 FLEX DECODER Troubleshooting No Backlighting Ensure the following before initiating this troubleshooting procedure: a. Verify the low cell indicator is not activated. If it is, change the primary battery. b. Verify the backlighting is activated correctly by pressing any of the buttons. NO BACKLIGHTING CHECK SIGNAL AT µC PIN 57 FAIL OK CHECK SIGNAL AT D5 FAIL REPLACE LED DRIVE CIRCUIT FAIL OK REPLACE DECODER BOARD Figure 2-11.
DECODER NP88 FLEX Troubleshooting Good Power-up Alert, but DOES NOT Page 1. 2. Ensure receiver connection is clean and free of debris. For waveform checks: a. Place the pager in receiver diagnostic mode. b. Connect the decoder to a known-good receiver with a receiver/decoder interconnect cable. DOES NOT PAGE CHECK CODEPLUG AND ENCODER HAVE PROPER CODE AND DATA POLARITY. SEE NOTE.
RECEIVER
NP88 FLEX 578 and 584 6881020B80 3VHF RECEIVER RECEIVER Contents 3VHF RECEIVER Contents Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1 Circuit Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2 Antenna and RF Amplifier . . . . . . . . . .
578 and 584 6881020B80 3VHF RECEIVER 3VHF RECEIVER NP88 FLEX RECEIVER Specifications Specifications FLEX Frequency Stability ±2.5 PPM from -10°C to +50°C (+25°C ref.
RECEIVER NP88 FLEX Circuit Description The following information describes the circuitry specific to the NP88 Flex 900MHz pager with a synthesizer receiver board. RF circuit structure of NP88 Flex 900MHz is as RF diagram. RF signal is received by antenna circuit, then get into RF-amplifier circuit which is low noise and high gain, signal is amplified about 20dB, afterwards pass through band pass filter to filter out noise.
NP88 FLEX RECEIVER Mixer Circuit Mixer is to mix RF signal (Fr) and first local oscillator signal (Flo), and it will bring the first intermediate frequency which is lower frequency (45MHz), the circuit composed of Q3, C17, R5, L3, C13, R4, R6 is bias. L3, C13 are Tank circuit. Q3 mixes Fr and Flo, then take out 45MHz first intermediate signal (IF1) by L3 and C13. IF1 = Fr – Flo. IF1 signal will couple to Crystal filter by through F1.
RECEIVER NP88 FLEX Tuning Synthesized receivers are tuned to the middle of the bandsplit at the factory for optimal performance across the band. To ensure optimal performance is maintained,execute the tuning download from the PPS to put the pager in the middle of the band. This frequency is called the “ tuning frequency” and is different for every band split. Alignment Procedure The NP88 Flex 900MHz pagers is aligned at the factory to provide peak performance over a long period of time.
NP88 FLEX RECEIVER Oscillator Frequencies Oscillator Frequencies- FLEX Pager Table 3-1. First and Second Oscillator Frequencies for FLEX 900MHz CARRIER FREQ. (MHz) :3:/1111.:43/1111 1ST OSC. FREQ. RANGE (MHz) 2ND OSC. FREQ. (MHz) 332.332/86 !!55/656 fc = 4fo + 45MHz (929.0000-932.
