Operating instructions

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COMMUNICATIONS SERVICE MONITOR

2948B

Operating Manual

Document part no. 46892/692

Summary of content (265 pages)

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COMMUNICATIONS SERVICE MONITOR 2948B Operating Manual Document part no.
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COMMUNICATIONS SERVICE MONITOR 2948B © Aeroflex International Ltd. 2007 No part of this document may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, or recorded by any information storage or retrieval system, without permission in writing by Aeroflex International Ltd. (hereafter referred to throughout the document as ‘Aeroflex’). Printed in the UK Manual part no.
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About this manual This manual explains how to use the Communications Service Monitor 2948B. It applies to instruments fitted with main software version 5.xx or later and cellular software version 5.xx. Intended audience People who need to test mobile radio systems and associated equipment. People who need to test airborne avionics receivers. Structure Chapter 1 General information and performance specification. Chapter 2 Gives installation instructions, including connection of peripheral equipment.
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About this manual (continued) Associated publications Other manuals that cover specific aspects of this service monitor are:• Programming manual (46882/683) provides programming information for remote control of the Service Monitor using MI-BASIC and GPIB. • Maintenance Manual (46882/694) provides servicing information for the Communications Service Monitor 2948B. Operating manual supplements provide operating details for specific system test software.
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Contents PRECAUTIONS.......................................................................................................................... v Chapter 1 GENERAL INFORMATION ................................................................................................. 1-1 Performance data....................................................................................................... 1-7 Chapter 2 INSTALLATION .....................................................................................
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PRECAUTIONS Precautions These terms have specific meanings in this manual: WARNING information to prevent personal injury. information to prevent damage to the equipment. important general information. Hazard symbols The meaning of hazard symbols appearing on the equipment and in the documentation is as follows: Symbol Description Refer to the operating manual when this symbol is marked on the instrument. Familiarize yourself with the nature of the hazard and the actions that may have to be taken.
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PRECAUTIONS Fuses Note that the internal supply fuse is in series with the live conductor of the supply lead. If connection is made to an unpolarized supply socket, it is possible for the fuse to become transposed to the neutral conductor, in which case, parts of the equipment could remain at supply potential even after the fuse has ruptured. WARNING Fire hazard Make sure that only fuses of the correct rating and type are used for replacement.
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PRECAUTIONS WARNING Tilt facility When the equipment is in the tilt position, it is advisable, for stability reasons, not to stack other equipment on top of it. Suitability for use This equipment has been designed and manufactured by Aeroflex to generate, receive and analyze RF/audio signals If the equipment is not used in a manner specified by Aeroflex, the protection provided by the equipment may be impaired.
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PRECAUTIONS Precautions Les termes suivants ont, dans ce manuel, des significations particulières: WARNING contient des informations pour éviter toute blessure au personnel. contient des informations pour éviter les dommages aux équipements. contient d'importantes informations d'ordre général.
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PRECAUTIONS WARNING Sécurité électrique (tension d’alimentation alternative) Cet appareil est protégé conformément à la norme CEI de sécurité Classe 1, c’est-à-dire que sa prise secteur comporte un fil de protection à la terre. Pour maintenir cette protection, le câble d’alimentation doit toujours être branché à la source d’alimentation par l’intermédiaire d’une prise comportant une borne de terre.
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PRECAUTIONS WARNING Surfaces chaudes Faire attention ,lors de la manipulation d'un connecteur "N", après l'injection de haute puissance en continu sur l'entrée RF de ce connecteur: Si une puissance supérieure à 50 W est envoyée pendant une longue durée, la température du connecteur peut être très élevée. WARNING Danger RF Lors de la mesure de T.O.S. de valeur importante, des tensions dangereuses dues aux ondes stationnaires peuvent apparaître sur l’alimentation.
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PRECAUTIONS Vorsichtsmassnahmen Diese Hinweise haben eine bestimmte Bedeutung in diesem Handbuch: WARNING dienen zur Vermeidung von Verletzungsrisiken. dienen dem Schutz der Geräte. enthalten wichtige Informationen. Gefahrensymbole Die Bedeutung der Gefahrensymbole auf den Geräten und in der Dokumentation ist wie folgt: Symbol Gefahrenart Beziehen Sie sich auf die Bedienungsanleitung wenn das Messgerät mit diesem Symbol markiert ist.
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PRECAUTIONS Sicherungen Die interne Sicherung in der Spannungszuführung ist in Reihe mit der spannungsführenden Zuleitung (braun) geschaltet. Bei Verbindung mit einer nicht gepolten Steckdose kann die Sicherung in der Masseleitung liegen, so daß auch bei geschmolzener Sicherung Geräteteile immer noch auf Spannungspotential sind. WARNING Feuergefahr Es dürfen nur Ersatzsicherungen vom gleichen Typ mit den korrekten Spezifikationen entsprechend der Stromaufnahme des Gerätes verwendet werden.
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PRECAUTIONS Eignung für Gebrauch Dieses Gerät wurde von Aeroflex entwickelt und hergestellt um HF/Audio Signale zu erzeugen, zu empfangen und zu analysieren Sollte das Gerät nicht auf die von Aeroflex vorgesehene Art und Weise verwendet werden, kann die Schutzfunktion des Gerätes beeinträchtigt werden. Aeroflex hat keinen Einfluß auf die Art der Verwendung und übernimmt keinerlei Verantwortung bei unsachgemässer Handhabung.
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PRECAUTIONS Precauzioni Questi termini vengono utilizzati in questo manuale con significati specifici: WARNING riportano informazioni atte ad evitare possibili pericoli alla persona. riportano informazioni per evitare possibili pericoli all'apparec-chiatura. riportano importanti informazioni di carattere generale.
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PRECAUTIONS Fusibili Notare che un fusibile è posto sul filo caldo (marrone) del cavo di alimentazione. Se l'alimentazione avviene tramite una presa non polarizzata, è possibile che il fusibile vada a protezione del neutro per cui anche in caso di una sua rottura, l'apparato potrebbe restare sotto tensione. WARNING Pericolo d'incendio Assicurarsi che, in caso di sostituzione, vengano utilizzati solo fusibili della portata e del tipo prescritti.
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PRECAUTIONS Caratteristiche d’uso Questo strumento è stato progettato e prodotto da Aeroflex generare, ricevere ed analizzare segnali RF/audio Se lo strumento non è utilizzato nel modo specificato da Aeroflex, le protezioni previste sullo strumento potrebbero risultare inefficaci. Aeroflex non può avere il controllo sull’uso di questo strumento e non può essere ritenuta responsabile per eventi risultanti da un uso diverso dallo scopo prefisso.
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PRECAUTIONS Precauciones Estos términos tienen significados específicos en este manual: WARNING contienen información referente a prevención de daños personales. contienen información referente a prevención de daños en equipos. contienen información general importante. Símbolos de peligro El significado de los símbolos de peligro en el equipo y en la documentación es el siguiente: Símbolo Naturaleza del peligro Vea el manual de funcionamiento cuando este símbolo aparezca en el instrumento.
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PRECAUTIONS Fusibles Se hace notar que el fusible de alimentación interno está enserie con el activo (marrón) del cable de alimentación a red. Si la clavija de alimentación de red no tiene polaridad, el fusible puede pasar a estar en serie con el neutro, en cuyo caso existen partes del equipo que permanecerían a tensión de red incluso después de que el fusible haya fundido. WARNING Peligro de incendio Asegúrese de utilizar sólo fusibles del tipo y valores especificados como repuesto.
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PRECAUTIONS Idoneidad de uso Este equipo ha sido diseñado y fabricado por Aeroflex para generar, recibir y analizar señales de RF/audio Si el equipo fuese utilizado de forma diferente a la especificada por Aeroflex, la protección ofrecida por el equipo pudiera quedar reducida. Aeroflex no tiene control sobre el uso de este equipo y no puede, por tanto, exigirsele responsabilidades derivadas de una utilización distinta de aquellas para las que ha sido diseñado.
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Chapter 1 GENERAL INFORMATION Contents Purpose and features ...................................................................................................................... 1-2 Transmitter testing .................................................................................................................. 1-3 Receiver testing....................................................................................................................... 1-4 Duplex testing....................................
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GENERAL INFORMATION Purpose and features 2948B is a portable Communications Service Monitor for carrying out production, routine and maintenance testing on radio transmitters, receivers and two way radio communication equipment. The SYSTEM mode provides test facilities for ILS, VOR and SELCAL receivers.
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GENERAL INFORMATION Transmitter testing Service Monitor MODULATED RF SIGNAL Tx Under Test AF GENERATOR OUTPUT AF (MODULATION) INPUT C3240 Fig. 1-1 Transmitter test set-up The transmitter test procedure uses:The AF generators, to provide a source of modulation for the transmitter under test. The RF power meter, to measure the mean output power level of the transmitter. The RF counter, to obtain the mean RF frequency of the transmitter output.
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GENERAL INFORMATION Receiver testing Service Monitor MODULATED RF TEST SIGNAL DEMODULATED AF SIGNAL Rx Under Test C3241 Fig. 1-2 Receiver test setup The receiver test procedure uses:The RF generator and the AF generators, to produce a transmission with defined parameters. The AF voltmeter, to measure the level of the demodulated signal from the receiver. The distortion meter, to obtain signal-to-noise ratio, SINAD levels and distortion percentage figures.
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GENERAL INFORMATION Service Monitor MODULATED RF TEST SIGNAL MODULATED RF SIGNAL DEMODULATED AF SIGNAL Rx/Tx Under Test AF GENERATOR OUTPUT C5385 Fig. 1-4 Two port duplex test setup Using the Duplex test facility, parameters for transmitter testing and receiver testing can be set up and displayed on one screen. This gives the capability to study the performance of duplex transceivers. Both one port and two port units can be tested.
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GENERAL INFORMATION Operating instructions for each of the SYSTEM test options is given in separate supplements to this manual. These supplements are supplied, as appropriate, with Service Monitors fitted with SYSTEM testing options. Avionics systems The Avionics SYSTEM test facility is capable of carrying out functional testing and performance evaluation of airborne radio navigation and communication equipment. Appendix B, Avionics System, covers the operation of this facility.
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GENERAL INFORMATION Performance data Receiver measurements RF signal generator Frequency Range 400 kHz to 1.05 GHz Resolution 10 Hz Indication 10 digit display Setting Keyboard entry, delta increment / decrement function and rotary control Accuracy As frequency standard Output Level Range Rx Test: N-Type socket: −141 dBm to −21 dBm BNC socket: −115 dBm to +5 dBm (usable to +7 dBm) Resolution 0.1 dB Indication 4 digits plus sign (dBm, dBμV, μV, mV, PD/EMF).
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GENERAL INFORMATION Amplitude Modulation – Internal Frequency range 400 kHz to 1.05 GHz AM depth range 0 to 99 % Resolution 1% Indication 2 digits Setting Keyboard entry, delta increment / decrement function and rotary control Accuracy For carrier frequencies from 1.
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GENERAL INFORMATION Audio analyzer Audio Voltmeter Input Impedance Nominally 1 MΩ in parallel with 40 pF Frequency Range DC and 20 Hz to 50 kHz AC only 20 Hz to 50 kHz Polarized DC (below 1 Hz) Maximum Input Voltage 30 V RMS, 50 V DC Level Ranges 0-100 mV to 0-100 V RMS in a 1,3,10 sequence Resolution 1 mV or 1% of reading Indication 3 digits and barchart Accuracy (AC) ±3% ±3 mV ± resolution up to 30 V RMS Accuracy (DC) ±1% +50 mV up to 40 V Audio Frequency Meter Frequency Range 20 Hz to 5
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GENERAL INFORMATION Audio Oscilloscope Operating Modes Single or repetitive sweep Frequency Range DC to 50 kHz, 3 Hz to 50 kHz AC coupled Voltage Range 10 mV to 20 V per division in a 1,2,5 sequence Voltage Accuracy ± 5 % of full scale FM Ranges ±75, 30, 15, 6, 3 and 1.
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GENERAL INFORMATION Transmitter measurements RF Frequency Meter Frequency Range 400 kHz to 1.05 GHz (manual tune) 10 MHz to 1 GHz (auto-tune) Resolution 1 Hz or 10 Hz, selectable, <1050 MHz 0.1 Hz, 1 Hz, 10 Hz up to 999 MHz Indication Up to 10 digits Accuracy As frequency standard ±resolution Acquisition Time Less than 1 second (manual). Typically 3 seconds (autotune) Sensitivity Autotuned: 5 mW (N-Type) 0.
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GENERAL INFORMATION Modulation Meter Sensitivity Autotuned: 5 mW (N-Type) 0.05 mW BNC (antenna port) Manual Tuned: −34 dBm (N-Type) −60 dBm BNC (antenna port) Auto or manual control of input attenuator Audio Filters Lowpass Filters Four independently configurable Lowpass filters LP1, LP2, LP3, LP4 that can be set to any frequency cut-off point from 250 Hz to 20,000 Hz (excluding the band 1001 to 2999 Hz). A 50 kHz Lowpass (No filters applied). 750 µs de-emphasis.
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GENERAL INFORMATION RF spectrum analyzer Frequency Range 400 kHz to 1.05 GHz Spans Continuously variable, 1 kHz / division to 100 MHz / division 1,2,5,10 increments Start / Stop frequency entry Resolution Bandwidth 300 Hz, 3, 30, 300 kHz, 3 MHz Reference Level (top of screen) −50 dBm to +52 dBm, 0.
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GENERAL INFORMATION Audio generators Frequency Frequency Range 5 Hz to 33 kHz Wave shape Sine or square Setting Keyboard entry, delta increment / decrement function and rotary control Indication 5 digits Resolution 0.1 Hz below 3.25 kHz 1 Hz above 3.25 kHz Accuracy 0.01 Hz <180 Hz 0.1 Hz >180 Hz Level Range 0.1 mV to 4 V RMS Setting Keyboard entry, delta increment / decrement function and rotary control Indication 4 digits Resolution 0.
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GENERAL INFORMATION Cellular and trunking Test Modes Auto test/manual test Auto Test Programs (dependent upon which Call processing only system is in use) Call and RF testing Brief testing Comprehensive testing Parametric Auto Test Routines AF frequency FM deviation Rx distortion Rx sensitivity Rx S/N Tx distortion Tx level Tx limiting Tx noise Tx S/N AF Level Mod frequency Rx expansion Rx SINAD Tx compression Tx frequency Tx power level Tx mod level Tx SINAD Registration/roaming update Place call Page
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GENERAL INFORMATION General General features Keyboard and Display` Display size Logical color-coded keyboard with bright high resolution LCD 160 x 85 mm RS232C interface is provided for printing or remote Service Monitor control.
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GENERAL INFORMATION Options and accessories Options Option 1 Option 2 Option 4 Option 5 Option 6 Option 8 Option 9 Option 10 Option 11 Option 12 Option 13 Option 14 Option 15 Option 16 600 Ω Matching Unit Analog Systems Card Parallel Interface † GPIB Interface † Memory Card Drive and Date/Time Stamp SSB Demodulator Occupied Bandwidth NMT AMPS TACS MPT1327 Require Option 2 to be fitted PMRTEST EDACS Radio Test EDACS Repeater Test Option 22 Option 23 Option 24 Option 25 Option 26 Option 29 Option 30 Option
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GENERAL INFORMATION Parallel Interface (Option 4) Allows direct connection of a parallel printer. Additionally provides 4 software programmable output lines. Printer port Connector 25 way female D-type Printers supported 75,100,150 dots per inch laser printers FX80, FX100 Epson format. Accessory port Connector 9 way female D-type Outputs 4 independently programmable output lines, each one configurable as a logic line or as a relay contact closure. +5V supply available.
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GENERAL INFORMATION PMRTEST Software (Option 14) USER DEFINED PMR for FM radios EDACSTM Radio Test Software (Option 15) Provides Auto/Manual test capability for EDACS™ radios. Up to four user-defined variants can be created and stored, each with up to 24 spot-channel frequencies EDACSTM Repeater Test Software (Option Provides Auto/Manual test capability for EDACS™ repeaters. Up to four user defined variants can be created and stored, each with 16) up to 24 spot-channel frequencies.
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GENERAL INFORMATION Supplied Accessories 43138/755 46882/692 46882/683 AC Supply lead* DC Supply lead Operating Manual Programming Manual *The AC supply lead provided with the Service Monitor will depend on the destination country.
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GENERAL INFORMATION EC Declaration of Conformity Certificate Ref. No.: DC256 The undersigned, representing: Manufacturer: Aeroflex International Ltd. Address: Longacres House, Six Hills Way, Stevenage, Hertfordshire, UK SG1 2AN Herewith declares that the product: Equipment Description: Model No.
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Chapter 2 INSTALLATION Contents Introduction.................................................................................................................................... 2-2 Initial visual inspection of new Service Monitors.......................................................................... 2-2 Ventilation ..................................................................................................................................... 2-2 Operational case (46662/571) shoulder strap..........
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INSTALLATION Introduction This chapter deals with preparing the Service Monitor for use for the first time and with the checks to be made when the Service Monitor may have been used under unknown conditions. The latter situation could well apply where the Service Monitor is used by several users for differing tasks. Initial visual inspection of new Service Monitors After unpacking the Service Monitor and before making any connections to a power source, inspect for any signs of mechanical damage.
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INSTALLATION Bail arm option If the bail arm carrying handle is fitted, the Service Monitor will not fit into the optional operational case, 46662/571. Do not attempt to attach the shoulder strap supplied with this operational case to a Service Monitor fitted with a bail arm carrying handle. Power requirements The Service Monitor can be powered from both AC and DC power sources.
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INSTALLATION This equipment is provided with a 3-wire (grounded) cordset which includes a molded IEC 60320-1 connector for connection to the equipment. The cable must be fitted with an approved plug which, when plugged into an appropriate 3-terminal socket outlet, grounds the case of the equipment. Failure to ground the equipment may expose the operator to hazardous voltage levels.
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INSTALLATION Français Le câble d'alimentation d'Europe Continentale est muni d'un connecteur mâle à angle droit type CEI83, standard C4 (CEE 7/7), qui peut être utilisé dans une prise femelle à ergot de terre (standard C 3b) ou à clips latéraux (standard C 2b), cette dernière étant communément appelée prise “Schuko” allemande. De la même façon que les autres connecteurs de type Schuko, celui-ci n'est pas polarisé lorsqu'il s'adapte à une prise femelle Schuko.
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INSTALLATION Connecting to a DC supply If the Service Monitor is to be used from a DC voltage source it should be connected using the supplied DC connecting lead. The polarity of the connections must be correct, RED to POSITIVE, BLACK to NEGATIVE. The negative connection of the DC supply is directly connected to the chassis of the Service Monitor and therefore to all screen connections of input and output connectors. Note however, that the AF ports are isolated under some operating conditions.
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INSTALLATION Accessory socket connections The accessory socket located on the front panel, is of the 7 pin DIN, 45° configuration. The function of each of the pins on this socket is shown in the following table. The pin numbering is shown in Fig. 2-2 Accessory in/out socket pin numbers, and is as viewed from the front of the Service Monitor. Table 2-1 Accessory socket pin numbering, location and functions Din pin No Function 6 Logic 1 Mic input/PTT-logic 4 Forward power 2 12 V DC at approx.
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INSTALLATION Selection logic [or data signals] on pins 1, 3 and 6 enables the Service Monitor to recognize the connections of an external accessory.
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INSTALLATION SERVICE MONITOR PC SERVICE MONITOR PC 9-WAY 9-WAY 9-WAY 25-WAY SG 5 5 SG SG 5 7 SG RXD 2 2 RXD RXD 2 3 RXD TXD 3 3 TXD TXD 3 2 TXD DTR 4 4 DTR DTR 4 20 DTR NOT CONNECTED 1 1 DCD NOT CONNECTED 1 8 DCD DSR 6 6 DSR DSR 6 6 DSR RTS 7 7 RTS RTS 7 4 RTS CTS 8 8 CTS CTS 8 5 CTS NOT CONNECTED 9 NOT CONNECTED 9 C3383 Fig.
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INSTALLATION Self tests and acceptance tests The service monitor incorporates a self test program which allows users to verify its condition at any time. This program is described below. When it is necessary to prove that the performance of the Service Monitor meets the published performance data, the Acceptance tests, described in Chapter 5, should be carried out. Self tests The built in Self Test program measures the output parameters of the RF generator using the transmitter test functions.
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INSTALLATION Test No 15 FM deviation. 50 kHz This test checks the signal generator FM deviation against the modulation meter reading. Related set-ups. Frequency 10 MHz, level -26 dBm, IF bandwidth 300 kHz, audio bandwidth 0.3 - 3.4 kHz, FM demodulation. The functions verified by the above tests are:Signal generator FM accuracy, modulation meter FM accuracy, modulation generator (audio generator) level accuracy. Modulation frequency. 1 kHz.
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INSTALLATION Routine safety testing and inspection In the UK the ‘Electricity at Work Regulations’ (1989) section 4(2) places a requirement on the users of equipment to maintain it in a safe condition. The explanatory notes call for regular inspections and tests together with a need to keep records. The following electrical tests and inspection information is provided for guidance purposes and involves the use of voltages and currents that can cause injury.
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INSTALLATION 3. Insulation tests A 500 V DC test should be applied between the protective earth connection and combined live and neutral supply connections with the equipment supply switch in the ‘on’ position. It is advisable to make the live/neutral link on the appliance tester or its connector to avoid the possibility of returning the Service Monitor to the user with the live and neutral poles linked with an ad-hoc strap. The test voltage should be applied for 5 seconds before taking the measurement.
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Chapter 3 LOCAL OPERATION Contents About this chapter .......................................................................................................................... 3-3 Front panel layout .......................................................................................................................... 3-4 Rear panel controls and connectors ............................................................................................... 3-8 Getting started...................................
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LOCAL OPERATION CTCSS ......................................................................................................................................... 3-77 Output level .......................................................................................................................... 3-77 Tone selection ....................................................................................................................... 3-77 Tone frequency shift ............................................
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LOCAL OPERATION List of figures Fig. 3-1 Front panel. ..................................................................................................................... 3-4 Fig. 3-2 Typical displays............................................................................................................... 3-5 Fig. 3-3 Rear panel layout, (with optional GPIB fitted). .............................................................. 3-8 Fig. 3-4. AF Filter HELP/SETUP page. .................................
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LOCAL OPERATION Front panel layout 1 2 3 17 communications service monitor 2948B LOCAL HELP/ SETUP REMOTE ANTENNA Tx TEST FREQ 7 8 9 Rx TEST LEVEL 4 5 6 s Dx TEST D INC SYSTEM ON OFF Hz 3 2 1 ms SPEC ANA MEM AF TEST DISPLAY HOLD dB 0 DELETE * E # A SINGLE F mV C VOLUME MEMORY CARD 1W MAX dBm RF IN/OUT SELECT ! 150W MAX DC SQUELCH 5 % dBmV D AC REP SCOPE 1W MAX B ENTER SUPPLY 4 kHz mV ms 16 ! MHz V AF GEN ACCESSORY AF INPUT OUT 6 15 FREQ
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LOCAL OPERATION Fig. 3-2 Typical displays The various keys on the front panel are grouped according to their use or located adjacent to associated items. (2) Soft keys. To each side of the display screen are six unmarked keys. These are the ‘Soft’ keys referred to in the display description above. The specific function of each of these keys is defined by the Service Monitor software and is indicated by the legend on the label immediately adjacent to it on the display screen. (3) Data Input keys.
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LOCAL OPERATION (6) N type RF connector. This is dual function, input and/or output. A 20 dB Delta attenuator is incorporated within the Service Monitor. This interconnects the 'N type' connector with the RF generator output and the measuring receiver input, through the input/output selector switching. WARNING Hot surfaces Take care when touching the RF Input N Type connector after the application of high levels of continuous power.
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LOCAL OPERATION DISPLAY HOLD key. To the left of the variable control is the [DISPLAY HOLD] key. Pressing this key at any time will freeze the display and prevent any adjustment to parameters displayed on the screen. The soft key menu changes to show two keys, [Store] and [Print]. The [Store] key, gives access to the STORE/RECALL screen and menu. The use of this feature is explained on page 3-91 The [Print] key is used to start the Screen Print function.
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LOCAL OPERATION Rear panel controls and connectors 21 22 DC SUPPLY - 23 24 ! + 11-32VDC 100W MAX T10AH250V AC SUPPLY 100-240V ~ 50-60Hz 108-118V ~ 50-400Hz 190VA T2AL250V SERIAL PORT EXT MOD IN DEMOD OUT EXT. STD 1/2/5/10MHz C5901 20 29 28 27 26 25 Fig. 3-3 Rear panel layout, (with optional GPIB fitted). On the rear panel of the Service Monitor are:(20) AC power supply input connector. One range for all mains voltages. See the Performance data section in Chapter 1.
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LOCAL OPERATION Getting started (Applying power and selecting test modes) The power ON-OFF switch, located on the front of the Service Monitor, will power up the Service Monitor from either an AC or DC supply. With a power source connected, switching on the Service Monitor will cause the cooling fan to operate and one of the test mode menus to be displayed. Which screen is displayed will depend on which store is selected as the 'Power Up From' store on setup page 2. See Setup page 2 on page 3-13.
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LOCAL OPERATION HELP/SETUP Pressing the [HELP/SETUP] key, at any time, will display the screen shown in fold out diagram (1-0), or a variation of it. Displaying the HELP/SETUP screen does not interrupt any ongoing operation or test. The center panel of the screen lists the following information:Serial number of the Service Monitor. Software fitted, with the version codes and Aeroflex part numbers. Options fitted to the Service Monitor (except Option 3).
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LOCAL OPERATION Setup page 1 This page allows the following optional settings to be selected. RF Counter Resolution 0.1 Hz/1 Hz/10 Hz The RF counter resolution can be set to 0.1 Hz, 1 Hz or 10 Hz. Selecting 1 Hz will slow the screen update rate by a factor of 10:1, selecting 0.1 Hz will slow it by a factor of 100:1. The choice is made by stepping through the three options using the soft key adjacent to the text.
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LOCAL OPERATION Low pass filters The four low pass preset filters can each be set to any frequency within the range 250 Hz to 1.0 kHz and 3.0 kHz to 20.0 kHz. The soft keys associated with the low pass filters are on the left of the setup page. To set the required frequency, first press the soft key relevant to the low pass filter to be set. The Freq: legend will become highlighted in reverse video. Use the Data Input keys to enter the required frequency and then press the appropriate termination key.
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LOCAL OPERATION Rx=Tx Offset Freq: Hz A setup option within the Tx TEST mode (Rx=Tx) will set the signal generator used for receiver testing to the measured frequency of a transmitter being tested. An Rx=Tx offset frequency entered here will cause the signal generator frequency to differ from the measured transmitter frequency by the offset frequency.
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LOCAL OPERATION Logic Lines The optional Accessory Port on the rear panel allows the control of external devices by logic control from the instrument. The use of this facility, how to make connections to it and how to set up the switching is explained under Accessory port (rear optional) starting on page 3-101 The state of the logic lines are set from the Set-up page accessed by pressing the [Logic Lines] soft key.
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LOCAL OPERATION Return Returns to the last screen displayed prior to the pressing of the Help/Setup mode key. Card Setup A section giving a detailed explanation of memory cards and their use will be found later in this chapter starting on page 3-94. This key displays the MEMORY CARD FORMAT screen and menu. The real time clock is also set from this screen. Return (on the HELP/SETUP screen) Returns to the last used main mode.
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LOCAL OPERATION Using the test modes Brief descriptions As the Service Monitor 2948 is a duplex instrument, the RF signal generator and the receiver circuits are able to operate simultaneously. This allows mobile transceivers to be tested under their normal operating conditions, with both their receiver section and transmitter section functioning. By selecting a particular test mode on the Service Monitor, one or both sections of the transceiver can be studied.
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LOCAL OPERATION AF TEST With AF TEST selected, the AUDIO TEST screen is displayed and access to the AF TEST features is available. See fold out diagram (7-0) at the end of this chapter. The RF generator is disabled. SYSTEMS The SYSTEM key gives access to the SYSTEM TEST mode. If any of the system test options have been provided on the particular Service Monitor, the user is able to carry out automatic and/or manual tests to pertinent equipment.
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LOCAL OPERATION Tx test (transmitter testing) Overview The Communications Service Monitor 2948 has been designed to test the performance of mobile communication equipment. This section explains the use of the Tx TEST mode. Typical uses are:• Performance checking following manufacture • Routine quality assurance testing • Workshop or field fault diagnosis etc. The operation of the Avionics SYSTEM function is explained in Appendix B, Avionics System.
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LOCAL OPERATION Connections AF VOLTMETER AF GEN 1 RF POWERMETER DISTORTION METER 20dB ATTENUATOR AF GEN 2 MODULATION METER AF FILTERS AF COUNTER TONES GEN RF COUNTER AF OSCILLOSCOPE SERVICE MONITOR AUDIO AMPLIFIER RF IN AF GEN OUT 'N' ANTENNA ALTERNATIVE CONNECTIONS Tx UNDER TEST C3373 Fig. 3-5 Transmitter test connections The transmitter and the Service Monitor are connected as shown in Fig. 3-5, Transmitter test connections.
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LOCAL OPERATION The Audio frequency input connection to the transmitter must be to the audio input, in place of the usual microphone input. This connection will vary for differing types of equipment. Points to note are:• The microphone must be disconnected, as any input from it would affect the performance of the test. • The microphone and its cable may complete the ‘keying’ circuit of the transmitter using a ‘press to talk’ switch, in which case an alternative arrangement must be provided.
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LOCAL OPERATION Manual frequency setting Range; 100 kHz to 1.05 GHz With the Tx FREQ legend highlighted, data can be entered from the keyboard to the Tx FREQ parameter. As the entry can only be a frequency setting, it is not necessary to select the orange [FREQ] key. Enter the required frequency by using the digit keys and the decimal point key if relevant.
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LOCAL OPERATION Tx power The [Tx Power] key gives access to RF power measurement functions or associated functions. Broad Band or Narrow Band power The [Broad/Narrow] key selects which of the RF power measurement methods is operative. The selected method is indicated on the display by the letters BB or NB to the right of the digital power reading. The use of this facility is explained under Making measurements later in this chapter. See page 3-27.
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LOCAL OPERATION Modulation meter, demodulation options setup Set up the demodulation options to be compatible with the transmission from the unit under test. Press the [Mod Meter] key. The soft keys change to the demod soft keys shown in fold out diagram (2-3). Modulation Type The Service Monitor can demodulate AM and FM signals. The demodulated signal is made available at the ‘DEMOD OUT’ connector on the rear of the Service Monitor. SSB signals can be demodulated if the SSB option is fitted.
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LOCAL OPERATION Audio frequency filtering The demodulated signal can be filtered using high pass, low pass or band pass audio filters and with weighting filters as required. Press the [AF Filter] key. The right hand soft keys change, to allow selection of AF filters as shown below. Press the [Return] key after selecting the required filter. High Pass † ‡ Low Pass CCITT† or C-MESS‡ Band Pass Deemph Only if option 23 (CCITT filter) is fitted. Only if option 24 (C-MESS filter) is fitted.
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LOCAL OPERATION SINAD Selects SINAD as the measurement method. The AF1 generator will be set to 1 kHz by this action, regardless of any previous setting. The distortion bar chart ranges available are 0 to 18 dB and 0 to 50 dB. The SINAD level is displayed as a digital readout above the bar chart. The TX TEST mode menu is recalled automatically after pressing this key. Dist’n Selects distortion percentage as the measurement method.
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LOCAL OPERATION Audio generator setup Freq. range 10 Hz to 20 kHz Level range 0.1 mV to 4 V RMS Shape option Sine or square To set up the audio generators in order to modulate the transmitter, press the [Audio Gen] key. This will display the audio setup menu shown in fold out diagram (2-4). Set up the audio generator(s) for the required frequency and output level by using the soft keys and data input keys:[Gen 1/Gen 2] to select AF1, then, [FREQ][n]....[n][kHz/Hz] [LEVEL][n]...
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LOCAL OPERATION Making measurements This section describes the actions needed to make measurements of each parameter associated with transmitter testing. All tests are described individually as ‘one off’ tests, but in practice, once set up, all active parameters will be measured simultaneously with continuous updating and the results displayed using the selected measurement units.
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LOCAL OPERATION The full-scale ranges of the RF power bar chart, are:10 mW to 100 kW in 15 steps of 1-3-10 sequence. 100 mV to 3 kV in 16 steps of 1-3-10 sequence. Directional power measurements Directional power and VSWR measurements can be made using the optional Directional Power Head accessory. The DIRECTIONAL POWER METER screen, accessed by pressing the [Dir Power] key, is used with these accessories.
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LOCAL OPERATION As the Spectrum Analyzer uses the same IF filters, the optimum filtering can be selected by examining the signal using the Spectrum Analyzer. Pressing the [Return] key will display the top level Tx TEST mode screen. If the operating mode of the Service Monitor is changed from Tx TEST mode with the harmonic analysis function selected, the harmonic analysis screen will be displayed again when Tx TEST mode is next selected.
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LOCAL OPERATION Marker A variable marker can be displayed, indicated by a fine dotted vertical line, with a read-out of the marker values displayed at the bottom of the screen. The marker reading provides two values: The absolute RF power level at the marker position (not the level relative to the Ref Level). A time difference of the position of the marker relative to the trigger point. If the marker, the Mkr legend and the relevant readings are not displayed, press the [Marker] key.
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LOCAL OPERATION Arming, triggering and storing The transient capture operation has three phases. The current phase is shown in inverse video at the bottom right of the display. The Armed phase is active when the transient analysis function is accessed. The level of any signal entering the selected RF input connector at the set transmitter frequency is displayed on the screen, if it is within the dynamic range currently being displayed.
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LOCAL OPERATION Fig. 3-8 Transient Analysis displays From this condition a permanent record can be made on a suitable printer by using the [DISPLAY HOLD], [Print], key sequence or stored to a memory card using the [DISPLAY HOLD], [Store], [Store Screen], key sequence. When the current display is no longer required, the Armed phase can be reset by pressing the [arm] key.
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LOCAL OPERATION Occupied Bandwidth This optional facility is used to evaluated the bandwidth occupied by the output from a transmitter. The display is a modified presentation of the spectrum analyzer display. For more information about the Spectrum Analyzer facility refer to the Spectrum Analyzer section of this chapter starting on page 3-55 . B5472 Fig.
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LOCAL OPERATION External attenuators Compensation for an external attenuator or test fixture included in the RF input path of the monitor can be programmed. The value, in dBs, of the attenuator should be entered in the RF Power Ext Atten: field of setup page 1. The value of the attenuator will then be included in power calculations and the power indicated by the power meter will be that at the input to the external attenuator. This feature makes use of the extended ranges of the power meter.
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LOCAL OPERATION Modulation characteristics Modulation frequency response and Companding/limiting The requirements of individual users will vary but the principle of the tests will be the same. A signal having a known level and frequency is applied to the AF input of the transmitter and the level of modulation produced is measured. To test the modulation characteristics of a transmitter with any degree of accuracy requires that the signal used to provide the modulation is accurately defined.
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LOCAL OPERATION *DUPLEX* All of the above information relating to modulation characteristics and frequency response testing also applies to tests made using the Dx TEST mode. The oscilloscope facility is not available when in Dx TEST mode. Modulation distortion dB dB Distortion Products Signal Filter Response Noise 1 a kHz Frequency 1 b dB Frequency kHz dB Filter Response Distortion Products Noise 1 c Noise kHz Frequency 1 d Frequency kHz C1640 Fig.
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LOCAL OPERATION The SINAD level is then calculated according to the formula:SINAD = 20 log = 20 log V1 dB V2 ( S + N + D) dB ( N + D) To obtain the distortion factor of a signal at the output of a transmitter the output level is measured and noted as for SINAD level measurement. A notch filter as used for SINAD measurement is used to make a second reading which will consist of the same values as for the second SINAD measurement.
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LOCAL OPERATION When in the Dx TEST mode, modulation distortion tests are not displayed.
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LOCAL OPERATION Rx test (receiver testing) Overview The Communications Service Monitor 2948 has been designed to test the performance of mobile communication equipment. This section explains the use of the Rx TEST mode. Typical uses are:• Performance checking following manufacture • Routine quality assurance testing • Workshop or field fault diagnosis etc. The dedicated Avionics SYSTEM function provides signals for testing ILS, VOR and SELCAL receivers.
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LOCAL OPERATION Connections MOD GEN 1 AF VOLTMETER AF FILTERS MOD GEN 2 DISTORTION METER RF GENERATOR 20dB ATTENUATOR AF COUNTER TONES GEN AF OSCILLOSCOPE RF OUT SERVICE MONITOR BNC 'N' AF IN ALTERNATIVE CONNECTIONS RF IN AF OUT Rx UNDER TEST C3374 Fig. 3-11 Receiver test connections Before making any connections between the Service Monitor and the receiver ensure that the RF generator of the Service Monitor is OFF.
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LOCAL OPERATION When testing the receiver section of a transceiver, ensure that the power output of the transmitter section will not exceed the power handling capability of the connector on the Service Monitor. Also ensure that the transceiver cannot be switched to ‘TRANSMIT’ inadvertently. The receiver and the Service Monitor should be connected as shown in Fig. 3-11 Receiver test connections. The block diagram of the Service Monitor shows the signal routing within it.
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LOCAL OPERATION Output level setting Range N-Type connector, -135 dBm to -15 dBm; 0.04 mV to 40 mV pd BNC connector, -115 dBm to +5 dBm; 0.4 mV to 400 mV pd (with uncalibrated overrange to +7 dBm) WARNING Hot surfaces Take care when touching the RF Input Type N connector after the application of high levels of continuous power. If 50 W is applied for a prolonged period, the temperature of the connector can become excessive. The signal generator output level is set using the data keys.
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LOCAL OPERATION Modulation generators Set up one or both of the modulation generators for the required frequency, level and shape by using the soft keys and data input keys. When these and the de-emphasis filter are set to the required settings press the [Return] key to restore the RECEIVER TEST menu. Modulation frequency and level The frequency range and level must not exceed the following limits:Modulating freq.
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LOCAL OPERATION Pre-emphasis filter The pre-emphasis filter can be switched in or out of circuit after pressing the [Mod Gen] key. Pressing the [Pre-emph] key will toggle the pre-emphasis filter into and out of circuit. The time constant of the filter is 750 µs, giving an increase with frequency of 6 dB/octave. The legend Pre-emph ON is displayed when the filtering is in circuit. No indication is given when the filtering is out of circuit.
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LOCAL OPERATION AF input level measurement The measured level of signals applied to the AF INPUT connector can be displayed in volts, dBm, dBV or mW. The selection is made from setup page 2, as described under Audio Level Measured in: on page 3-13. When the input level is displayed in dBm or mW, the signal is assumed to be measured across 600 Ω. The 600 Ω interface unit allows the Service Monitor to provide a 600 Ω termination. (See Audio Input Impedance: on page 3-13.
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LOCAL OPERATION Off Disables any active distortion measuring function and removes the distortion bar chart from the display. Hint. By disabling this function, the time taken to measure the remainder of the measurement functions is shortened thereby reducing the update time. S/N Selects Signal to noise ratio as the measurement method.
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LOCAL OPERATION Making measurements (Examples of receiver tests). The procedure for making each of the tests listed in the receiver testing overview, above, follows. Some of the tests may require separate operations and others will only require a reading to be made. Sensitivity Receiver sensitivity is defined as the minimum RF level required at the antenna to produce an intelligible output of the modulated information. The problem with the above definition is that of defining ‘intelligible output’.
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LOCAL OPERATION 20 dB weighted SINAD sensitivity This test is very similar to the 12 dB SINAD sensitivity test The differences are firstly that the SINAD level specified is 20 dB and secondly that a psophometric weighting filter is included in the test path. This filter imposes a frequency response characteristic to the signal similar to that of the human ear response. There are two specifications of filter in common use. One is the European standard CCITT and the other is the American C-MESS.
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LOCAL OPERATION Basic sensitivity test To carry out a basic sensitivity test on an AM receiver: Set the RF generator frequency to that required by the test program. This setting can be entered using the data input keys or set using the Rx=Tx facility discussed under Tx mode. The RF generator can be switched off during the setup operation if required, by pressing the orange [ON OFF] function key. Select the ‘Mod Gen’ menu from the RECEIVER TEST screen. Set the modulation frequency and level.
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LOCAL OPERATION Selectivity 2041 Signal Generator 'ADJACENT CHANNEL' SIGNAL Coupler Service Monitor 'ON CHANNEL' SIGNAL DE MODULATED AF TEST SIGNAL Rx Under Test C3375 Fig. 3-12 Selectivity test setup Selectivity tests are measurements of the capability of a receiver to differentiate between a wanted signal and an unwanted signal, usually that transmitted on an adjacent channel.
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LOCAL OPERATION Blocking (or desensitization) Blocking (or desensitization) is an undesirable response by a receiver to a signal whose frequency is spaced from the wanted signal by a frequency difference greater than the adjacent channel spacing. The interfering signal will enter the IF pass band of the receiver with sufficient strength to cause the automatic gain control to operate. This will reduce the gain of the receiver and ‘block out’ weak signals.
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LOCAL OPERATION The procedure for measuring the IF rejection ratio is similar to that used to measure image frequency rejection and uses the same setup. The RF reference level is found at the RF frequency to which the receiver is tuned, then the RF generator is retuned to the IF frequency of the receiver under test. The RF output level is increased until a 20 dB SINAD level is obtained. The output level of the RF generator is noted.
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LOCAL OPERATION Dx test (duplex testing) TONES GEN RF GEN. ➤ ➤ MOD METER POWER METER MOD GEN 1 RF COUNTER AF COUNTER AF FILTERS DISTORTION METER SERVICE MONITOR MOD GEN 2 BNC RF OUT AF OUT AF VOLTMETER 20dB ATTEN. ANTENNA 'N' RF IN RF IN/OUT AF IN AF IN AF OUT TRANSCEIVER UNDER TEST C3376 Fig. 3-14 One port duplex test setup Overview With the Dx TEST mode selected, the screen and menu shown in fold out diagram (4-0) is displayed.
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LOCAL OPERATION RF GEN. ➤ ➤ TONES GEN MOD METER POWER METER MOD GEN 1 RF COUNTER AF COUNTER AF FILTERS DISTORTION METER SERVICE MONITOR MOD GEN 2 AF VOLTMETER 20dB ATTEN. AF OUT BNC RF OUT 'N' ANTENNA RF IN RF OUT AF IN RF IN AF OUT AF IN TRANSCEIVER UNDER TEST ➤ ➤ ➤ ➤ SERVICE MONITOR SERVICE MONITOR 20dB ATTEN. RF BNC OUT 20dB ATTEN. RF 'N' IN RF OUT RF BNC OUT ANTENNA RF IN RF OUT 'N' RF IN ANTENNA RF IN C3377 Fig.
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LOCAL OPERATION Systems The [SYSTEM] mode key gives access to dedicated options for testing mobile communications systems such as AMPS and TACS cellular mobile radio telephone systems and MPT 1327 mobile radio trunking systems. Supplementary operating manuals are provided with Service Monitors fitted with these options. The same key also gives access to systems specifically designed to test Avionics navigation and communication equipment. Appendix B, Avionics System, describes the use of this facility.
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LOCAL OPERATION Overview With the SPEC ANA mode selected, the screen and menu shown in fold out diagram (6-0) is displayed. In the SPEC ANA mode, the sweep generator causes the acceptance frequency of the analyzer input circuits to repeatedly sweep over the selected frequency range. The level of RF signal present at the active RF input connector is measured at regular points along the sweep and plotted progressively across the display, thus building up a graph of RF level against frequency.
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LOCAL OPERATION Start frequency Pressing the [Start Freq] key allows the required start point to be entered using the data entry keys. The variable control is active when the Start legend is highlighted. Note that when using the variable control the span of the display remains constant. Therefore the stop frequency will follow any change to the start frequency. This is not the case when entering a start frequency by using the data keys.
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LOCAL OPERATION Vertical scale The vertical scale can be displayed with a range of 10 dB/division or 2 dB/division. To select the vertical range, press the [Vert Scale] key which will cause the menu shown in fold out diagram (6-2) to be displayed. Repeated presses of the [10 dB/2 dB] key will switch the reference level between the options, with the current choice being shown in the display.
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LOCAL OPERATION Tracking generator facility The tracking generator facility uses the RF generator of the Service Monitor to provide a tracking signal source. This allows the spectrum analyzer to show the frequency response of frequency dependent circuits such as filters. The frequency response of any circuit connected between the tracking generator output and the spectrum analyzer input will be displayed.
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LOCAL OPERATION Look and Listen LOCAL OSCILLATOR ! I/O SWITCHING RECEIVER CIRCUITS SWEEP GEN. RF DET. LOG. AMP. AM/FM DEMOD AUDIO AMP. OSCILLOSCOPE ! 20 dB ATTEN. B1417 Fig. 3-18 Spectrum analyzer setup, Look and Listen function The Look and Listen facility allows the Service Monitor to be used for ‘OFF-AIR’ monitoring of transmissions while examining the area of radio spectrum on which the transmission being monitored is centered.
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LOCAL OPERATION The Span setting controls the sweep range covered by the spectrum analyzer. When in the Look and Listen mode the sweep span is selected from the Span menu accessible by pressing the [Span] key. Four span widths are available as listed below. 1 MHz 500 kHz 200 kHz 100 kHz Demod settings The ‘listen’ demodulator and its associated circuits are set to extract the information from the signal tuned to the center frequency of the display.
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LOCAL OPERATION Input sensitivity The input sensitivity of the Service Monitor in the Look and Listen mode is the same as for the normal spectrum analyzer input. The reference level can be set using the data input keys, or adjusted using the variable control. The LEVEL [×] and [Ø] keys adjust the reference level in either 2 dB or 10 dB steps depending on the setting of the reference level vertical range.
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LOCAL OPERATION AF test (audio frequency testing) Overview TONES GEN AF COUNTER AF GEN 1 AF FILTERS DISTORTION METER SERVICE MONITOR AF GEN 2 AF VOLTMETER AF OUT AF IN AF OUT AF IN AMPLIFIER UNDER TEST C3380 Fig. 3-19 Audio test setup To enter the AF TEST mode press the blue [AF TEST] key. This will cause the screen and menu shown in fold out diagram (7-0) to be displayed.
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LOCAL OPERATION To select and set up the audio generators press the[Audio Gen] key. This will display the audio setup menu shown in fold out diagram (7-2). Repeated presses of the [Gen1/Gen2] key will highlight the AF1 and AF2 legends in turn to indicate the selected generator. Set up the audio generator(s) for the required frequency and output level by using the soft keys and data input keys:[Gen 1/Gen 2] to select AF1, then, [FREQ][n]....[n][kHz/Hz] [LEVEL][n]...
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LOCAL OPERATION Input filtering The AF signal to the AF INPUT connector on the front panel can be filtered using high pass, low pass or band pass audio filters and with weighting filters as required. Press the [AF Filter] key. The right hand soft keys change, to allow selection of AF filters as shown below. Press the [Return] key after selecting the required filter. High Pass † ‡ Low Pass Band Pass CCITT† or C-MESS‡ Only if option 23 (CCITT filter) is fitted.
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LOCAL OPERATION SINAD Selects SINAD as the measurement method. The AF generator is set to 1 kHz and the 1 kHz distortion notch filter is switched alternatively in and out of circuit, with the signal level being measured by the AF voltmeter in each state. See Fig. 3-10 a, b, & c, Distortion level and signal to noise level measurements, on page 3-36.
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LOCAL OPERATION Dist’n Selects distortion percentage as the measurement method. The AF generator is set to 1 kHz and the 1 kHz distortion notch filter is switched alternatively in and out of circuit, with the signal level being measured by the AF voltmeter in each state. See Fig. 3-10 a, b, & c, Distortion level and signal to noise level measurements, on page 3-36.
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LOCAL OPERATION Incremental adjustment keys General This section provides information on the use of the incremental adjustment keys. Other sections of this chapter have specific references to these keys; this section gives general information. The incremental adjustment keys are located under the variable control, with one pair designated FREQ, [×] and [Ø], the other pair designated LEVEL, [×] and [Ø].
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LOCAL OPERATION Assigning The assignment of the incremental keys is shown in the display, along with the step value. To assign a parameter to a pair of keys, first select the parameter as if to change the value using the data input keys, but rather than entering a new value press the orange [ALT ∆] key. Now enter the value of the step to be incremented at each keypress, followed by the correct terminator key.
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LOCAL OPERATION Tones Tones sub-mode Audio tones and digital code signals are used for many purposes within radio communication systems. The Service Monitor has a TONES mode accessed from the Tx TEST, Rx TEST, Dx TEST and AF TEST modes. This gives facilities for testing tone calling and control systems of the following types. • Sequential Tones. A selective calling system using audio tones. • CTCSS (Continuous Tone Coded Squelch System). • DCS (Digitally Coded Squelch).
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LOCAL OPERATION Signal routing The tones sub-mode can be entered from either Tx TEST, Rx TEST, Dx TEST or AF TEST modes. The encoded signal produced by the Service Monitor can be routed to the equipment under test in two ways: • As a modulated RF signal from either of the RF output connectors. • As an AF signal from the AF GEN OUT connector.
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LOCAL OPERATION Sequential tones Overview Sequential tones signaling systems use sequences of audio tones to control various functions of a radio system. There are many systems in operation world-wide, all using up to 15 tones labeled with the hexadecimal digits 0 to E with ‘No Tone’ as F. Some systems make use of extended tones for certain functions. Each version has its own tone allocation tables for the 15 tones and its own timing for tone duration.
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LOCAL OPERATION Fig. 3-21 RF Sequential tones encoder display, main menu Setting the Tones mode The display is divided into three areas. • At the bottom of the display is a table listing the frequencies allocated to the 15 tones, 0 to E. Above the table is shown the system type, i.e. CCIR, ZVEI etc. • At the top of the display is a panel in which the tone sequence to be transmitted is assembled or edited. • The center of the display shows information relating to the parameters of the system.
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LOCAL OPERATION Creating the tone sequence To create the required tone sequence, first press the [Enter Sequ] key to display the cursor in the tone sequence panel. Enter the required sequence by using any of the data entry keys 1 to 9, zero and the Hex digits A to E. The [Extend Tone] key is used to convert a standard tone to an extended tone or an extended tone to a standard tone.
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LOCAL OPERATION Tone ON/OFF control When the RF SEQUENTIAL ENCODER screen or the AF SEQUENTIAL ENCODER screen is displayed, the sequential tones are turned on or off by the orange [ON/OFF] function key. If the sequential tones are ON and the Tx TEST, Rx TEST, Dx TEST or AF TEST mode selected, the tones will continue to be generated. If the tones out routing has been set to give RF tones, this is provided by modulation generator 1.
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LOCAL OPERATION The underlined tones are listed in the center of the display with an analysis of the parameters of each tone as below:• The measured frequency of each tone. • The percentage error from the true tone frequency. • The duration of each tone. By using the [ E ] or [ F ] keys, the analysis of all tones in the decoded sequence can be shown. The stored sequence can be cleared from the store by pressing the [Clear Sequ] key. Revertive tones Revertive tones signaling takes various forms.
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LOCAL OPERATION CTCSS The CTCSS tones system uses a continuous tone at a precise frequency, transmitted below the audio pass band, to unsquelch the receiver. Fig. 3-24 RF CTCSS encoder screen and menu Pressing the [CTCSS] key on the TONES selection screen will display the screen shown in Fig 3-24, RF CTCSS encoder screen and menu. The CTCSS function of the Service Monitor will generate a single AF tone, selected from those listed on the display.
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LOCAL OPERATION Tone ON/OFF control When the RF CTCSS ENCODER screen or the AF CTCSS ENCODER screen is displayed, the tone is turned on or off by the orange [ON/OFF] function key. If the CTCSS tone is ON and the Tx TEST, Rx TEST, Dx TEST or AF TEST mode selected, the CTCSS tone will continue to be generated. If the tones out routing has been set to give RF tones, this is provided by modulation generator 2. The legend --CTCSS-- will be displayed against MOD2 FREQ on the RECEIVER TEST or DUPLEX screens.
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LOCAL OPERATION DCS Overview Digitally Coded Squelch signaling is a system for addressing mobile radio transceivers from their base station by transmitting a code unique to the addressed transceiver for the duration of the transmission. The principles and limitations of the system provide 104 uniquely identifiable codes for use on any one RF channel.
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LOCAL OPERATION Check the modulation polarity of the transceiver. For positive modulation the polarity should be set to Normal and for negative modulation, set to Inverted. The [Polarity] key toggles between these two options. To enter or change the DCS code for the transceiver to be tested, first press the [Code] key to highlight the legend DCS Code:. Key in the code using the data entry keys. The Service Monitor will accept any octal sequence in the range 0 to 777.
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LOCAL OPERATION DTMF Overview Dual Tone, Multi-Frequency. The DTMF tones function will generate and decode sequences, of up to 40 characters corresponding to the standard DTMF frequencies. The encoder allows the user to create characters sequences which are routed to the AF GEN OUTPUT connector or to the RF generator modulators. The decoder will accept up to 40 tone pairs, either from the modulation meter output or as AF signals from the AF INPUT connector.
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LOCAL OPERATION Rx test DTMF tones function In the Rx TEST mode, with [Tones Out] set to RF, the encoder output is fed to the RF generator and the tones used to modulate the RF signal. The DTMF decoder within the receiver under test can then be tested. When setting up the Service Monitor to test the DTMF decoder of a receiver, commence as for normal Rx tests.
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LOCAL OPERATION When the DTMF TONES functions are set, return to the Rx TEST mode and enable the RF generator. Return to the DTMF RF ENCODER function. Press the [Send Mode] key to display the Send Mode menu. The options available are:[Cont Tones] Generates the tone sequence repeatedly until the orange [ON/OFF] function key is pressed. [Tone Burst] Generates one sequence of the tones then stops. [Step Tones] The first press causes the first tone of the sequence to be generated for the duration specified.
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LOCAL OPERATION AF Tone Remote Overview The AF Tone Remote system is a remote control facility for controlling remote transceivers of two-way radio systems by sending AF tones over the dedicated fixed voice circuit from the control point to the transmitter. There are two formats in general use. The Sequential Tone format sends a Guard Tone of (usually) 2.175 kHz and 40 ms, followed by a function tone such as 1.950 kHz, 1.850 kHz or 1.
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LOCAL OPERATION POCSAG Overview The POCSAG system is an international standard for radio pager operation. The system operates by broadcasting digital messages on a common frequency, only alerting the addressed radio pager when the transmitted address matches that of the pager. The signal transmitted consists of two main elements, the address and the message. The POCSAG test facility within the Service Monitor generates a paging signal containing all elements of a ‘live’ signal.
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LOCAL OPERATION The radio identification code (RIC) of the radio pager is set by the user. This is entered into the Service Monitor as a seven digit decimal number corresponding to the 21 bit address code of the radio pager. The number is unique to the radio pager and will have a maximum decimal equivalent of 2097151. Leading zero can be omitted from the entry of RIC to save time.
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LOCAL OPERATION Testing a radio pager Radio pagers are self-contained units with no external antenna provision, therefore it is not possible to make a direct RF connection between the Service Monitor and the pager. The Service Monitor output can be taken from the BNC RF output connector using the telescopic antenna accessory (Aeroflex part no. 54421/001) or similar, where suitable screening is available. Alternatively, a TEM cell may be preferable.
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LOCAL OPERATION Decoding POCSAG type signals The POCSAG DECODE option allows signals containing data formatted to the POCSAG specification to be decoded and displayed. Decoding of either numeric or alpha-numeric messages is selectable. The decoder can be set to respond to and display:Only messages addressed to a specified RIC number. Only messages containing the sequence 12345. All messages.
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LOCAL OPERATION Oscilloscope The digital oscilloscope option is available from within the Tx TEST, Rx TEST and AF TEST modes. There are two display functions: The standard display with a viewing area of approximately 38 × 70 mm. The expanded display with a viewing area of approximately 63 × 96 mm. The oscilloscope display may or may not be shown when the Tx TEST, Rx TEST or AF TEST modes are selected.
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LOCAL OPERATION Expanded display With the expanded display selected, the area of the display available for digital readings is limited. The following table shows the data that can be displayed in each test mode. Tx Test Rx Test AF Test Tx FREQ OFFSET POWER MOD FREQ AUDIO FREQ AUDIO FREQ FM/AM LEVEL LEVEL LEVEL SINAD, S/N, DISTORTION SINAD, S/N, DISTORTION SINAD, S/N, DISTORTION Persistence The persistence of the scope trace can be selected to suit the user’s requirements.
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LOCAL OPERATION Stores, settings/results Overview A section of the non-volatile RAM in the Service Monitor is designated as a user store for Service Monitor settings and results. 'Power Down' and 'Factory Pre-set' settings are also held in this area of memory. The memory card option extends the 'User store' facility, by providing additional memory and by allowing screen bitmaps, 'SYSTEM' settings, 'SYSTEM' results and 'SYSTEM User Defined' test programs to be stored.
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LOCAL OPERATION Recalling Results When 'Results' are recalled, the RESULTS SCREEN is displayed. The test results are shown against each of the parameter headings. Results of tests made when in the Dx TEST mode are shown with the RECEIVER TEST results in the top half of the display and the TRANSMITTER TEST results in the bottom half.
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LOCAL OPERATION Deleting store contents To delete the contents of an unprotected store location, proceed as follows:Press the [Delete] key. The inverse video message, 'Delete Store No.' will be displayed. Key in the two digit address of the location to be deleted, using the data entry keys. The contents will be deleted as soon as the second digit is keyed and the location address list will show the location as 'Empty'. Once deleted, the contents cannot be retrieved.
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LOCAL OPERATION Memory card The optional memory card facility extends the scope of the memory facility by the use of a 'Smart Card' containing non-volatile static RAM with battery back-up. The card should have at least 128 k of memory. Information loaded onto a card is not unique to the source Service Monitor. The data on memory cards can be read onto other equipment using a suitable card reader. A memory card is loaded into the memory card port located on the front panel of the Service Monitor.
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LOCAL OPERATION Write-protecting cards The contents of memory cards can be protected from accidental overwriting or erasure by using the differing methods of protection available on the Service Monitor and the memory cards. Write protect card switch Setting the write-protect switch, on the non-contact end of the memory card, offers a physical method of protecting the card contents.
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LOCAL OPERATION Unlocking stores Insert the card in the Service Monitor and access the MEMORY CARD FORMAT screen as described above. The legend 'Locked' will be shown against the [Change Code] and [Lock Stores] keys. Press the [Lock Stores] key, which will cause the message Enter Code to be displayed. Key in the four figure code number and press the [ENTER] key. If the correct code number has been entered the 'Locked' legend will no longer be displayed.
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LOCAL OPERATION Storing system MI-BASIC programs User defined SYSTEM test programs, which are written in MI-BASIC, can be stored on memory cards as explained above. These must be down-loaded into the Service Monitor before they can be transferred onto a memory card. Printing from memory cards The contents of memory card store locations, with the exception of SYSTEM test results, can be sent directly to a printer, without recalling into the Service Monitor display.
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LOCAL OPERATION Error messages There are a number of error messages associated with the store facility, which will be displayed, for approximately 10 seconds, under certain conditions. These are listed below. *** ERROR Store Empty *** *** ERROR Card Not Formatted *** *** ERROR Store Protected *** *** ERROR No Card Present *** *** ERROR No Card Interface *** *** ERROR Card Directory Full *** The recalled store location is empty.
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LOCAL OPERATION Real time clock. Date and time stamping Purpose The memory card option also contains a real time clock, with date and time stamping facilities. The date and time is printed on all screen dump printouts. Data stored on memory cards also has date and time fields. This information is not visible on the Service Monitor, but is included so as to be visible when memory card files are viewed on a DOS style file display.
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LOCAL OPERATION Printer An RS232 printer can be driven by the Service Monitor when connected to the SERIAL PORT on the rear panel. Complete screen images and hard copy of stored test results can be printed. The serial port must be set to the printer option through ‘Setup Page 2’ and the [Remote Control] key. The port must be configured to match the requirements of the printer, using the port configuration menu, also accessible through ‘setup page 2’, and the [serial port] key.
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LOCAL OPERATION Accessory port (rear optional) As well as the parallel printer output, this option also provides an accessory port which allows the control of external devices by logic control from the Service Monitor. Fig. 3-32, Rear accessory port socket connections, shows the pin numbering of the socket and Table 3-2, Rear accessory port connections, shows the function of the socket connections. Fig. 3-31, Simplified diagram of rear accessory port switching shows the switching associated with the port.
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LOCAL OPERATION Pin Connections 5 1 9 6 Fig.
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LOCAL OPERATION Logic line control Additional control is provided to logic lines 0 and 1, from the two top soft keys on the left of the logic line setup menu. When set to ‘As setting’, the output will be as set by the right-hand soft keys. When the ‘Line 0 Mode’ is set to ‘Close for Transmit’, the state of this line will depend upon which operating mode the Service Monitor is set to.
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LOCAL OPERATION LOCAL HELP/ SETUP Tx TEST HELP/ SETUP Dx TEST SYSTEM SPEC ANA AF TEST SINGLE To Printer: ON/ CHARGE Trim A3 printed sheets by 0.75" (19mm) from right edge to clear binder. Rx TEST B5889 Test mode screen and menu (1.0). HELP/SETUP with next levels.
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LOCAL OPERATION Fold out diagram number 3-106 (1.
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LOCAL OPERATION LOCAL HELP/ SETUP Tx TEST Tx TEST Dx TEST SYSTEM SPEC ANA AF TEST SINGLE To Printer: ON/ CHARGE Trim A3 printed sheets by 0.75" (19mm) from right edge to clear binder. Rx TEST B5890 Test mode screen and menu (2.0). Tx TEST with next levels.
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LOCAL OPERATION Fold out diagram number 3-108 (2.
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LOCAL OPERATION LOCAL Rx TEST HELP/ SETUP Tx TEST Rx TEST SYSTEM SPEC ANA AF TEST To Printer: SINGLE Trim A3 printed sheets by 0.75" (19mm) from right edge to clear binder. Dx TEST B5891 Test mode screen and menu (3.0). Rx TEST with next levels.
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LOCAL OPERATION Fold out diagram number 3-110 (3.
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LOCAL OPERATION LOCAL HELP/ SETUP Tx TEST Dx TEST Rx TEST SYSTEM SPEC ANA AF TEST SINGLE To Printer: ON/ CHARGE Trim A3 printed sheets by 0.75" (19mm) from right edge to clear binder. Dx TEST B5892 Test mode screen and menu (4.0). Dx TEST with next levels.
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LOCAL OPERATION Fold out diagram number 3-112 (4.
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To Printer: Trim A3 printed sheets by 0.75" (19mm) from right edge to clear binder. LOCAL OPERATION Test mode screen and menu (5.0). SYSTEMS with next levels.
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LOCAL OPERATION Fold out diagram number (5.
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LOCAL OPERATION LOCAL HELP/ SETUP Tx TEST SPEC ANA Rx TEST SYSTEM SPEC ANA AF TEST SINGLE ON/ CHARGE To Printer: Peak Find Trim A3 printed sheets by 0.75" (19mm) from right edge to clear binder. Dx TEST B5893 Test mode screen and menu (6.0). SPEC ANA with next levels.
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LOCAL OPERATION Fold out diagram number (6.
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LOCAL OPERATION LOCAL HELP/ SETUP Tx TEST AF TEST Rx TEST SYSTEM SPEC ANA AF TEST SINGLE To Printer: ON/ CHARGE Trim A3 printed sheets by 0.75" (19mm) from right edge to clear binder. Dx TEST B5894 Test mode screen and menu (7.0). AF TEST with next levels.
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LOCAL OPERATION Fold out diagram number (7.
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Chapter 4 TECHNICAL DESCRIPTION Contents Overview........................................................................................................................................ 4-1 Power supply .......................................................................................................................... 4-2 The display.............................................................................................................................. 4-3 Tx test mode............................
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TECHNICAL DESCRIPTION Power supply CONTROL BOARD AC - DC CONVERTER DC - DC CONVERTER DC OUTPUT +24V -24V +12V +5V -12V 0V DC INPUT 11 - 32V COOLING FAN ON/OFF AC INPUT 90 - 264V 45 - 440Hz C5903 Fig. 4-1 Block diagram of power supply module. The power supply module is a switched mode design which will operate from an AC supply of either 100 to 240 V~ at a frequency of 50 to 60 Hz, or within the range 108 to 118 V~, at a frequency of 50 to 400 Hz; or from a DC supply of 11 to 32 V.
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TECHNICAL DESCRIPTION The DC output circuits producing the four output supplies are each fed from an individual winding on the DC-DC converter output transformer. Regulation is applied to the DC-DC converter from the output current and voltage sensing circuits. Current monitoring to provide regulation is obtained from the three common-return supplies and voltage monitoring from the +5 V supply. The 36 V output is generated by adding a 24 V floating supply onto the +12 V supply rail.
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To Printer: Trim A3 printed sheets by 0.75" (19mm) from right edge to clear binder. TECHNICAL DESCRIPTION Fig.
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TECHNICAL DESCRIPTION Tx test mode When operating in the Tx TEST mode the Service Monitor has to provide a source of modulation for the transmitter being tested, and also analyze the RF output signal from the transmitter. Modulation sources The modulating signal is provided by one or both of the audio generators or the data generator and is taken from the AF GEN OUT connector on the front panel. A B A.F.
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TECHNICAL DESCRIPTION Instruction as to the frequency of the required signal is latched into a programmable array device, which generates a repetitive digital output sequence recurring at the required frequency. The digital output from the programmable array is transferred as a stream of 13 bit parallel data into an EPROM. This holds look-up tables containing shape details of sine wave and square wave signals.
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TECHNICAL DESCRIPTION Receiver circuits Input switching TO OVERLOAD WARNING CIRCUIT BNC RF OUT OVERLOAD DETECTOR FROM RF GENERATOR VIA ATTENUATOR ➤ ’N’ TYPE RF IN/OUT TO FIRST FREQUENCY CHANGER VIA ATTENUATOR 0/10dB ATTEN. 25kHz POWER LEVEL 9mV FOR +7dBm AT ’N TYPE’ INPUT TO OVERLOAD WARNING CIRCUIT 20dB ATTEN. ➤ 0/10dB ATTEN. AGC AMPLIFIER 25kHz 1V RMS 25kHz DETECTOR - INTEGRATOR + BNC ANTENNA RF IN OVERLOAD DETECTOR LIMITER RF DETECTOR TO OVERLOAD WARNING CIRCUIT C1411 Fig.
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TECHNICAL DESCRIPTION Overload detection An overload detection circuit is activated if power in excess of 1.0 W is applied to the BNC antenna connector or to the BNC RF output connector. The overload detect lines are activated and trigger the overload warning message from the microprocessor. A temperature sensor is in physical contact with the 20 dB pad on the ‘N type’ connector. This triggers the overload circuit in the event of excessive power being applied to that connector.
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TECHNICAL DESCRIPTION Third frequency changer/mixer A 3rd frequency change is made to the signal to achieve a final IF of 10.7 MHz. The local oscillator signal for the 3rd mixer is provided by the voltage controlled oscillator on the 2nd and 3rd oscillator board A10. This oscillator runs at 90 MHz and for normal transmitter testing is locked to the output of a 90 MHz reference oscillator on the 2nd and 3rd oscillator board A9/1. Bandwidth filters The 10.7 MHz output from the 3rd mixer passes to the 10.
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TECHNICAL DESCRIPTION After leaving the gain control circuit, the signal is then mixed in a double balanced mixer with a 10 MHz signal from the reference oscillator. The output from the mixer will contain a 625 kHz component. This is passed through a 625 kHz low pass filter to one input of another double balanced mixer. The second input is fed with a reference signal of 625 kHz derived from the 10 MHz reference through a ‘divide by 16’ circuit.
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TECHNICAL DESCRIPTION Rx test mode The Rx TEST mode requires a modulated RF signal to be fed to the receiver. The AF signal produced by the demodulator within the receiver, is analyzed to produce results of the test. Selecting the Rx TEST mode does not disable the functions of the Tx TEST mode. The receiver circuits remain active at their last settings. The AF generators will also continue operating at their last settings unless either is enabled as a modulation generator.
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TECHNICAL DESCRIPTION C5 0.4 - 72 MHz 1280 MHz 320 MHz f f/4 C4 0.4 - 1050 MHz C3 576 - 1152 MHz 288 - 576 MHz 144 - 288 MHz f f/N 72 - 144 MHz C2 576 - 720 MHz 720 - 912 MHz C1 f f/2 912 - 1155 MHz AF3 Σ f Frac N f/N ➤ 2.5 MHz Ι f f/N FM MODULATION INPUT (ANALOGUE) 10 MHz REF FM 1 BIT MODULATION C3260 Fig.
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TECHNICAL DESCRIPTION Modulators The Rx TEST signal can be either AM or FM modulated. The selected modulation signal, is obtained from either or both of the AF generators, from the data generator or from an external source. It is conditioned and level corrected within the modulation control circuits on the audio processor board (B1/1 or B1/2). Frequency modulation is applied by injection into the fractional N control loop, thereby influencing the generated frequency.
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TECHNICAL DESCRIPTION Oscilloscope function When used in the Rx TEST mode, the oscilloscope displays the AF input signal fed to the AF input connector. The signal is passed through a sensitivity control circuit for scope calibration before following the same path as used in the Tx TEST mode. Dx test mode The Dx TEST mode uses all the circuit elements described in the proceeding sections. The technical description is valid for all three modes.
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TECHNICAL DESCRIPTION Systems mode The systems mode of the Service Monitor allows it to test communications equipment which is designed for operation on dedicated systems such as cellular mobile radio telephone systems and trunking radio telephone systems. Automatic testing is performed using various test programs. These can be made to check all functions of the system, the signaling only or any intermediate choice of functions, depending on the user's requirements.
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Chapter 5 ACCEPTANCE TESTING Contents Introduction.................................................................................................................................... 5-2 Results tables .......................................................................................................................... 5-2 Before starting ........................................................................................................................ 5-2 Test equipment............................
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ACCEPTANCE TESTING Introduction Test procedures described in this chapter may be simplified and of restricted range compared with those that relate to the generally more comprehensive factory test facilities which are necessary to demonstrate complete compliance with the specifications. Performance limits quoted are for guidance and should not be taken as guaranteed performance specifications unless they are also quoted in the section Performance data in Chapter 1.
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ACCEPTANCE TESTING Test equipment Description Minimum specification Example Frequency counter 400 kHz to 1.05 GHz 1 Hz resolution, external standard In/Out IFR* 2440 or EIP 25B RF power meter ± 0.1 dB from 10 MHz to 1 GHz IFR* 6960/A/B + 6912 and 6920 sensor Measuring receiver −21 dBm to −127 dBm, 2.
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ACCEPTANCE TESTING RF output tests Carrier frequency accuracy This check provides a conventional method of checking the signal generator's frequency locking circuitry. It will confirm correct operation of phase lock loop and dividers. Overall accuracy is determined by the instrument's internal reference standard. Specification Frequency range: 400 kHz to 1.
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ACCEPTANCE TESTING Table 5-1 Carrier frequencies Frequency UUT area checked 2440 range 400.000 kHz Oscillator, bottom A 1050.00000 MHz Oscillator, top C 500.00000 MHz Oscillator, middle B 188.88888 MHz 177.77777 MHz 166.66666 MHz 155.55555 MHz 144.44444 MHz 133.33333 MHz 122.22222 MHz 111.
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ACCEPTANCE TESTING RF output level Specification Level range: −141 dBm to −21 dBm (N-type socket) Accuracy: ± 2 dB up to 1 GHz Test equipment Description Minimum specification Example RF power meter ± 0.1 dB from 10 MHz to 1 GHz IFR 6960/A/B + 6920 sensor Measuring receiver −21 dBm to −127 dBm, 2.5 MHz to 1 GHz HP 8902A + 11772A sensor Spectrum analyzer Noise floor < −127 dBm IFR 2383 UUT RF power meter N TYPE OUTPUT 6920 SENSOR INPUT C2581 Fig.
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ACCEPTANCE TESTING BNC output mode No claim is made on the output level accuracy of the BNC socket. The following is a functional check to ensure correct internal operation. (1) Connect the 6920 sensor to the BNC output, as shown in Fig. 5-2. (2) Set the UUT to [Rx TEST], RF IN/OUT [SELECT] BNC output, [RF Gen], [LEVEL] −21 dBm, [FREQ] 10 MHz. All modulation and noise measurements should be switched OFF. (3) Check that the power meter indicates −21 dBm ± 4 dB.
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ACCEPTANCE TESTING Alternative attenuator functional check Spectrum analyzer UUT N TYPE OUTPUT C2583 Fig. 5-4 Attenuator functional check (1) Connect the test equipment as shown in Fig. 5-4. (2) Set the UUT to [Rx TEST], RF IN/OUT [SELECT] N-type output, [RF Gen], [LEVEL] −27 dBm, [Δ INC] 10 dB, [FREQ] 251 MHz. All modulation and noise measurements should be switched OFF. (3) Tune the Spectrum analyzer to the signal from the UUT.
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ACCEPTANCE TESTING Spectral purity Harmonics, spurious, RF carrier leakage, residual FM Specification Carrier range: 400 kHz to 1.05 GHz Harmonics: Better than −25 DBE Spurious signals Better than −30 dBc Residual FM Less than 12 Hz RMS (0.3 to 3.
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ACCEPTANCE TESTING (7) To confirm the low residual FM of the UUT, the use of an extremely low-noise FM demodulator is necessary; this is achieved by using the IFR 2041 Low-noise signal generator as the local oscillator for the 2305. Connect the test equipment as shown in Fig. 5-6 (8) Refer to Results table 5-8 on page 5-34. Set the UUT to [Rx TEST], RF IN/OUT [SELECT] BNC output, [RF Gen], [LEVEL] 0 dBm, [ FREQ], 1000 MHz. Switch all modulation generators and noise measurements off.
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ACCEPTANCE TESTING Amplitude modulation Specification Carrier range: 400 kHz to 1.05 GHz Resolution: 1% Accuracy ±5% of setting ± 1 digit for modulation frequency 1 kHz, 50% Test equipment Description Modulation meter Minimum specification Example RF I/P 500 kHz to 400 MHz AM Measurement accuracy up to 85% depth:- ±1% of reading at 1 kHz mod rate IFR 2305 Modulation meter UUT BNC OUTPUT RF INPUT C2587 Fig. 5-7 Internal AM accuracy checks (1) Refer to Results table 5-9 on page 5-34.
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ACCEPTANCE TESTING Frequency modulation Specification Carrier range 400 kHz to 1.05 GHz Accuracy† ±7% ± 10 Hz at 1 kHz modulating frequency † At low modulation levels the residual AM/FM may become significant Test equipment Description Modulation meter Minimum specification Example RF I/P 500 kHz to 1.05 Ghz. FM measurement accuracy ±0.5% of reading ±1 least significant digit at 1 kHz mod rate for deviation > 5 kHz. IFR 2305 Modulation meter UUT BNC OUTPUT RF INPUT C2587 Fig.
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ACCEPTANCE TESTING AF output tests Audio generator output level Specification Level range: 0.1 mV to 4 V RMS Accuracy: ±5% ± resolution 50 Hz to 15 kHz Test equipment Description Minimum specification DVM Example 1 % accuracy 50 Hz to 15 kHz Solatron 7150+ UUT DVM AF GEN OUTPUT VOLTMETER INPUT TERMINALS C2588 Fig. 5-9 Audio generator level accuracy checks (1) Refer to Results table 5-12 on page 5-35. Connect the test equipment as shown in Fig.
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ACCEPTANCE TESTING Audio generator distortion Specification Less than 0.5% at 1 kHz Distortion: Less than 1% from 50 Hz to 15 kHz Test equipment Description Minimum specification Distortion analyzer Example Capable of measuring distortion from 1 kHz to 15 kHz down to 0.1%. IFR 2965 or HP8903B Distortion analyzer UUT AF GEN OUTPUT AF INPUT C2589 Fig. 5-10 Audio generator signal purity checks (1) Refer to Results table 5-14 on page 5-36.
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ACCEPTANCE TESTING Audio generator frequency This is a functional check only. The Audio generator frequency is derived digitally and provided that the hardware is operational its accuracy will be maintained. The instrument’s internal reference frequency is checked elsewhere. This check is listed at this point as it is one of the AF generator tests, but it should be carried out after the UUT audio frequency meter has been checked (see AF input tests; AF frequency meter).
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ACCEPTANCE TESTING AF input tests Audio frequency meter This test confirms the accuracy of the audio counter hardware. Overall accuracy is governed by the instrument reference frequency. The reference is checked independently elsewhere. Note: If the LF generator is not available then the Audio generator frequency check will confirm that the audio frequency meter is functional. Specification Frequency range: 20 Hz to 50 kHz Resolution: 0.
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ACCEPTANCE TESTING Audio voltmeter Specification Level accuracy: ±3% ±3 mV ± resolution 20 Hz to 50 kHz, AC ±1% ±50 mV ± resolution, DC Resolution: 1 mV or 1% of reading Test equipment Description Minimum specification Example LF generator 50 Hz to 50 kHz 30 mV to 5 V RMS DC power supply 0 to 50 V IFR 2965 DVM DC measurement and AC measurement 20 Hz to 50 kHz Solatron 7150+ LF generator UUT AF INPUT AF GEN OUTPUT DVM VOLTMETER INPUT TERMINALS C2591 Fig.
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ACCEPTANCE TESTING (5) This step is a functional check only and confirms that the audio filters switch in correctly with minimal insertion loss. Press [HELP/SETUP], [Setup], [AF Filters], [Factory Preset], [Return], [Return], [Return]. • Set the UUT AF filter to 15 kHz LP and check that the UUT voltmeter indicates within ±6% ±3 mV ± resolution of the level measured with the 50 kHz LP. • Repeat with the 300 to 3.4 kHz BP filter. • Repeat with the 50 to 15.0 kHz BP filter.
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ACCEPTANCE TESTING RF input tests Modulation analyzer - FM Specification Frequency range: 400 kHz to 1.05 GHz Modulation frequency range: 10 Hz to 15 kHz Deviation range: 0 to 75 kHz Resolution: 10 Hz below 2 kHz deviation 1% above 2 kHz deviation Accuracy (see Note 1) ±5% ± resolution at 1 kHz modulation frequency Demodulation scope accuracy ±10% Demodulation output socket 200 mV peak to peak ± 10% per 1 kHz deviation Demodulation filters 300 Hz LP, 3 kHz LP, 0.3 to 3.
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ACCEPTANCE TESTING Signal generator RF OUTPUT Modulation meter UUT ANTENNA INPUT RF INPUT Splitter C2592 Fig. 5-13 Modulation meter FM (5) Check that the deviation level indicated on the UUT is within ±5% ± resolution of the deviation indicated on the external Modulation meter. (6) Repeat steps 4 and 5 for RF carrier frequencies of 500 MHz and 1000 MHz. (7) Refer to Results table 5-22 on page 5-39. On the UUT select an AF filter of 0.3 to 3.4 kHz and an IF filter of 3 kHz.
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ACCEPTANCE TESTING (20) Check that the deviation reading on the UUT drops by approximately half, i.e. to 37.5 kHz. (functional check). (21) Press [Deemph] to switch the de-emphasis filter off and then [Return], [Scope/Bar], [Bar Chart], [Return], to switch the oscilloscope off. (22) Remove the splitter and Modulation meter and connect the RF signal generator directly to the UUT antenna input.
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ACCEPTANCE TESTING Modulation analyzer - AM Specification Frequency range: 400 kHz to 1.05 GHz Modulation frequency range: 10 Hz to 15 kHz AM depth range: 0 to 99% (manually tuned) Resolution: 1% AM Accuracy (see Note 1) ±5% ±1 digit at 1 kHz ±8.5% ±1 digit, 50 Hz to 10 kHz Residual AM: Less than 1% (0.3 to 3.4 kHz) Note: (1) At low modulation levels, the residual AM/FM may become significant. Test equipment Description Minimum specification Example RF signal generator 500 kHz to 1 GHz.
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ACCEPTANCE TESTING (2) Set the Modulation meter to monitor AM in a 50 Hz to 15 kHz bandwidth, Noise averaging on. Press [HELP/SETUP], [Setup], [AF Filters], [Factory Preset], [Return], [Return], [Return]. (3) Set the UUT to [Tx TEST], RF IN/OUT [SELECT] antenna input socket, [Mod Meter]. Press the [AM/FM] soft key to set the UUT to demodulate AM. From the power up default, the instrument should already have an IF filter of 30 kHz and AF filter of 0.3 to 3.4 kHz selected.
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ACCEPTANCE TESTING RF frequency meter Specification Frequency range: 400 kHz to 1.05 GHz Resolution: 0.1 Hz, 1 Hz or 10 Hz selectable Accuracy As frequency standard ± resolution Sensitivity autotuned 5 mW (N-type), 0.05 mW (antenna port) Sensitivity manual tuned −34 dBm (N-type), −60 dBm (antenna port) Test equipment Description Minimum specification Example RF signal generator 400 kHz to 1.05 GHz IFR 2965 or IFR 2041 RF power meter ±0.
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ACCEPTANCE TESTING (8) Disconnect the external reference from the UUT and connect an external reference with an accuracy of 1 part in 10 9 or better to the RF signal generator. (9) Refer to Results table 5-31 on page 5-41. Set the RF signal generator to provide a frequency of 1000 MHz at a level of 0 dBm. (10) Check that the UUT indicates a frequency between 999.999750 MHz and 1000.000250 MHz.
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ACCEPTANCE TESTING RF spectrum analyzer Specification Frequency range: 400 kHz to 1.0 GHz Resolution bandwidth 300 Hz, 3, 30, 300 kHz, 3 MHz Display dynamic range: 80 dB Noise floor Typically 75 dB below top of screen On screen linearity: Typically ± 2 dB ± resolution (10 dB/div) (10 dB above the noise floor) Resolution: 0.1 dB on 2 dB/ division 0.
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ACCEPTANCE TESTING (7) Reduce the RF signal generator RF level until the trace sits on the graticule line 2 divisions down from the top line. Check that the level set on the RF signal generator is 20 dB down from reading 1 ±3 dB (functional test only). (8) Reduce the RF signal generator RF level until the trace sits on the graticule line 3 divisions down from the top line. Check that the level set on the RF signal generator is 30 dB down from reading 1 ±3 dB (functional test only).
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ACCEPTANCE TESTING RF broadband power meter Specification Frequency range: 200 kHz to 1.05 GHz Accuracy: ± 10% ± resolution (N-type) Resolution: 0.1 dB Test equipment Description Minimum specification Example Calibrated RF power source consisting of:- Accuracy better than 3.
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ACCEPTANCE TESTING (3) Set the calibrated power source to provide a signal at 11 MHz and 100 mW(+20 dBm) to the UUT input. Note the level on the UUT broadband power meter and check that it is within the stated specification. Repeat at 100 MHz and then in 100 MHz steps up to and including 1000 MHz. (4) Set the calibrated power source to provide 100 MHz and 100 mW. Press [SELECT] on the UUT to select N-type input/output, i.e. both LEDs above the N-type socket on.
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Acceptance Test Results Tables For 2948B [ ] , serial number _ _ _ _ _ _ / _ _ _ Results table 5-1 Carrier frequency accuracy Frequency Lower limit 400.000 kHz Upper limit 399.999 400.001 Result _______ 1050.00000 MHz 1049.999999 1050.000001 _______ 500.00000 MHz 499.999999 500.000001 _______ 188.88888 MHz 188.888879 188.888881 _______ 177.77777 MHz 177.777769 177.777771 _______ 166.66666 MHz 166.666659 166.666661 _______ 155.55555 MHz 155.555549 155.555551 _______ 144.
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ACCEPTANCE TESTING Results table 5-3 ALC linearity at 10 MHz Level (dBm) Lower limit Upper limit Result −21 −23.0 −19.0 _______ −22 −24.0 −20.0 _______ −23 −25.0 −21.0 _______ −24 −26.0 −22.0 _______ −25 −27.0 −23.0 _______ −26 −28.0 −24.0 _______ −27 −29.0 −25.0 _______ −28 −30.0 −26.0 _______ −29 −31.0 −27.0 _______ −30 −32.0 −28.0 _______ −31 −33.0 −29.0 _______ −32 −34.0 −30.0 _______ −33 −35.0 −31.0 _______ −34 −36.0 −32.0 _______ −35 −37.
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ACCEPTANCE TESTING Results table 5-5 ALC linearity at 1000 MHz Level (dBm) Lower limit Upper limit Result −21 −23.0 −19.0 _______ −22 −24.0 −20.0 _______ −23 −25.0 −21.0 _______ −24 −26.0 −22.0 _______ −25 −27.0 −23.0 _______ −26 −28.0 −24.0 _______ −27 −29.0 −25.0 _______ −28 −30.0 −26.0 _______ −29 −31.0 −27.0 _______ −30 −32.0 −28.0 _______ −31 −33.0 −29.0 _______ −32 −34.0 −30.0 _______ −33 −35.0 −31.0 _______ −34 −36.0 −32.0 _______ −35 −37.
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ACCEPTANCE TESTING Results table 5-8 Residual FM test points UUT RF generator frequency (MHz) Local oscillator frequency (MHz) Limits (Hz) Result 1000 55.63889 12 _______ 925 54.50000 12 _______ 730 52.25000 12 _______ 502 55.94444 12 _______ 240 48.30000 12 _______ 12 _______ 20 Results table 5-9 AM versus carrier frequency (50% depth at 1 kHz rate) Carrier frequency (MHz) Lower limit (%) Upper limit (%) Result (%) 1.5 46.5 53.5 _______ 50 46.5 53.5 _______ 100 46.
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ACCEPTANCE TESTING Results table 5-11 FM linearity checks (at 600 MHz carrier frequency 1 kHz rate) Deviation frequency (kHz) Lower limit (kHz) Upper limit (kHz) Result 75 69.74 80.26 _______ 50 46.49 53.51 _______ 25 23.24 26.76 _______ 5 4.64 5.
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ACCEPTANCE TESTING Results table 5-14 Audio generator 1 distortion AF generator 1 frequency (Hz) Level (mV) Distortion upper limit (%) 1000 4000 0.5 _______ 0.5 _______ 1000 100.0 Result 2000 4000 1.0 _______ 5000 4000 1.0 _______ 15000 4000 1.0 _______ Results table 5-15 Audio generator 2 distortion AF generator 2 frequency (Hz) Level (mV) 1000 4000 1000 Distortion upper limit (%) 100.0 Result 0.5 _______ 0.5 _______ 2000 4000 1.0 _______ 5000 4000 1.
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ACCEPTANCE TESTING Results table 5-17 Audio generator 2 frequency (functional) AF generator 2 setting Lower limit Upper limit Result 10 Hz 9.9 Hz 10.1 Hz _______ 500 Hz 499.9 Hz 500.1 Hz _______ 1.0000 kHz 1.1111 kHz 999.9 Hz 1.1110 1000.1 Hz kHz 1.1112 kHz _______ _______ 2.2222 kHz 2.2221 kHz 2.2223 kHz _______ 3.333 kHz 3.3328 kHz 3.3332 kHz _______ 4.444 kHz 4.4438 kHz 4.4442 kHz _______ 5.555 kHz 5.5548 kHz 5.5552 kHz _______ 6.666 kHz 6.6658 kHz 6.
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ACCEPTANCE TESTING Results table 5-19 Audio voltmeter accuracy Frequency DVM reading (mV) UUT * upper limit (mV) † UUT * lower limit (mV) ‡ 25.1 34.
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ACCEPTANCE TESTING Results table 5-22 FM measurement versus deviation level (1 kHz rate) Deviation level IF bandwidth Lower limit (kHz) † Upper limit (kHz) † 250 Hz ‡ 3 kHz 0.2275 0.2725 10 kHz 30 kHz 50 kHz 300 kHz 47 53 _______ 75 kHz 300 kHz 70.5 79.5 _______ † ‡ 9.4 10.6 Result _______ _______ The upper and lower limits in Results table 5-21, and Results table 5-22 are calculated on the assumption that it was possible to set the exact level on the external Modulation meter.
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ACCEPTANCE TESTING Results table 5-27 AM measurement versus AM depth (1 kHz rate) Depth (%) Lower limit (%) † 5 Upper limit (%) † 3.75 20 6.25 Result _______ 18 22 _______ 50 46.5 53.
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ACCEPTANCE TESTING Results table 5-29 RF frequency meter (at −60 dBm antenna input, manual tuned) Carrier frequency (MHz) Offset lower limit (Hz) Offset upper limit (Hz) Result 10 −1 1 _______ 500 −1 1 _______ 1050 −1 1 _______ Results table 5-30 RF frequency meter (at −13 dBm (0.05mw) antenna input autotuned) Carrier frequency (MHz) Lower limit (MHz) Upper limit (MHz) Result 1000 999.999999 1000.000001 _______ 500 499.999999 500.000001 _______ 10 9.999999 10.
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ACCEPTANCE TESTING Results table 5-33 RF broadband power meter (N-type input) Frequency (MHz) Input level (dBm) Lower limit (dBm) Upper limit (dBm) Result N-input 11 20 19.4 20.5 _______ 100 20 19.4 20.5 _______ 200 20 19.4 20.5 _______ 300 20 19.4 20.5 _______ 400 20 19.4 20.5 _______ 500 20 19.4 20.5 _______ 600 20 19.4 20.5 _______ 700 20 19.4 20.5 _______ 800 20 19.4 20.5 _______ 900 20 19.4 20.5 _______ 1000 20 19.4 20.5 _______ 100 20 19.
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Appendix A DIRECTIONAL POWER HEADS Contents Features......................................................................................................................................... A-7 Performance data - power head only............................................................................................. A-8 Performance data - in conjunction with 2948B .......................................................................... A-10 Additional parts associated with directional power head......
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DIRECTIONAL POWER HEADS Precautions These terms have specific meanings in this manual: WARNING information to prevent personal injury. information to prevent damage to the equipment. important general information.
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DIRECTIONAL POWER HEADS Précautions Les termes suivants ont, dans ce manuel, des significations particulières: WARNING contient des informations pour éviter toute blessure au personnel. contient des informations pour éviter les dommages aux équipements. contient d'importantes informations d'ordre général.
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DIRECTIONAL POWER HEADS Vorsichtsmaßnahmen Diese Hinweise haben eine bestimmte Bedeutung in diesem Handbuch: dienen zur Vermeidung von Verletzungsrisiken. WARNING dienen dem Schutz der Geräte. enthalten wichtige Informationen. Gefahrensymbole Die Gefahrensymbole auf den Geräten sind wie folgt: Symbol Gefahrenart Hochfrequenz Warnung vor giftigen Substanzen Sicherheit Dieses Gerät wurde in Übereinstimmung mit BS4743 und IEC 348 entwickelt und geprüft.
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DIRECTIONAL POWER HEADS Precauzioni Questi termini vengono utilizzati in questo manuale con significati specifici: WARNING riportano informazioni atte ad evitare possibili pericoli alla persona. riportano informazioni per evitare possibili pericoli all'apparecchiatura. riportano importanti informazioni di carattere generale.
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DIRECTIONAL POWER HEADS Precauciones Estos términos tienen significados específicos en este manual: contienen información referente a prevención de daños personales. WARNING contienen información referente a prevención de daños en equipos. contienen información general importante.
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DIRECTIONAL POWER HEADS Features This accessory is produced by IFR Ltd for use with certain of their Radio Test Sets and Communications Service Monitors. It is used to measure forward power, reverse power and VSWR in coaxial RF transmission lines and antenna systems. There are two versions as follows:Frequency range Part no. 1 to 50 MHz (HF) 25 to 1000 MHz (UHF) 54421/002 54421/003 There are no controls fitted to the Directional Power Head.
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DIRECTIONAL POWER HEADS Performance data - power head only HF version UHF version Frequency range: 1 MHz to 50 MHz 25 MHz to 1000 MHz Power measurement (either direction) See Fig. A-2 See Fig.
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DIRECTIONAL POWER HEADS RF connectors Type: N sockets N sockets Characteristic impedance: 50 Ω nominal 50 Ω nominal Insertion SWR: <1.1:1 (return loss >26.4 dB) at 1 to 50 MHz <1.1:1 (return loss >26.4 dB) at 25 to 1000 MHz Insertion loss: <0.05 dB <0.35 dB at up to 520 MHz, <0.
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DIRECTIONAL POWER HEADS Performance data - in conjunction with 2948B When the Power Head is used in conjunction with the Communications Service Monitor 2948, the performance is identical to that of the Power Head alone with the exceptions and additions given below. HF version UHF version Power measurement Resolution: 1 mW or 0.
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DIRECTIONAL POWER HEADS CW POWER CW POWER MAX SAFE POWER 1000W MA 1000W X S AFE PO WE R CW INDICATION ONLY 100W 100W 10W 10W 1W 1W 100mW 100mW 10mW 10mW CW INDICATION ONLY CW INDICATION ONLY 1mW 1mW 1 10 20 30 40 50 FREQUENCY MHz 25 = PEP INDICATION RANGE = CW FULL SPEC. RANGE 200 400 600 800 1000 FREQUENCY MHz = PEP INDICATION RANGE = CW FULL SPEC. RANGE C1377 Fig. A-1 Power range of HF directional power head Fig.
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DIRECTIONAL POWER HEADS VSWR CURVE BETWEEN POINTS A & B REPRESENTS MINIMUM POWER REQUIRED FOR ACCURATE VSWR MEASUREMENTS 100:1 FULL SPEC. LIMIT OF HF POWER HEAD AND MAX. INDICATION LIMIT OF UHF POWER HEAD UP TO 520 MHz. SEE NOTE. FULL SPEC. LIMIT OF UHF POWER HEAD. EXTENDS TO 200 W UP TO 200 MHz. SEE NOTE. INDICATION ONLY FOR THESE SIGNAL LEVELS 3:1 A NOTE REFER TO FIG. 1-2 FOR INDICATION RANGE AND MAX.
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DIRECTIONAL POWER HEADS Table A-1 Conversion of VSWR to return loss VSWR Return loss (dB) VSWR Return loss (dB) VSWR Return loss (dB) VSWR Return loss (dB) 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 1.11 1.12 1.13 1.14 1.15 1.16 1.17 1.18 1.19 1.20 ∞ 46.1 40.1 36.6 34.2 32.3 30.7 29.4 28.3 27.3 26.4 25.7 24.9 24.3 23.7 23.1 22.6 22.1 21.7 21.2 20.8 1.21 1.22 1.23 1.24 1.25 1.26 1.27 1.28 1.29 1.30 1.32 1.34 1.36 1.38 1.40 1.42 1.44 1.46 1.48 1.50 1.52 20.4 20.1 19.7 19.4 19.1 18.
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DIRECTIONAL POWER HEADS Using the directional power head accessory General The supplied accessory consists of the Power Head together with the 3 metre Cable Assembly. Power supply No additional power supply is required. 12 V DC is supplied to the Power Head from the Service Monitor, through the cable assembly. Procedure WARNING RF HAZARD. No attempt should be made to connect the Directional Power Head to an RF line until the "Operating Precautions" on page v have been noted.
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DIRECTIONAL POWER HEADS The bar charts can be set for auto-ranging or manual range selection. Repeated presses of the [Bchart Select] key selects each bar chart in turn. The selected bar chart is indicated by an A or H being shown in inverse video at the left end. Pressing the [Autorange] key will switch the selected bar chart to auto-ranging, indicated by an inverse video A.
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DIRECTIONAL POWER HEADS Technical description Directional coupler assembly The directional coupler is connected in series with the RF line under test and senses forward and reverse RF power. The coupler has two outputs, one for forward power and the other for reverse power. Because the coupler can be connected in either direction on the RF line, either output could represent forward or reverse power. Each output from the coupler is routed to an RF detector.
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DIRECTIONAL POWER HEADS DIRECTIONAL COUPLER CH. 1 +12V FROM TEST SET RF LINE UNDER TEST CH. 2 TO CHANNEL 2 RF DETECTOR AND CHANNEL 2 CIRCUIT HYBRID POWER SUPPLY & OSCILLATOR CIRCUIT HYBRID CONTROL CIRCUIT HYBRID CONTROL FROM TEST SET 1 kHz RF DETECTOR (CHANNEL 1) CW PATH INTEGRATOR CW AGC ➤ CHANNEL 1 POWER LEVEL TO TEST SET PEP LF DETECTOR (CHANNEL 1) DIRECTIONAL COUPLER ASSEMBLY PEAK BUFFER PEP PATH CHANNEL 1 CIRCUIT HYBRID C1363 Fig.
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Appendix B AVIONICS SYSTEM Contents Avionics system overview ........................................................................................................... B-2 General description ....................................................................................................................... B-2 ILS ................................................................................................................................................ B-2 Marker beacons............................
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AVIONICS SYSTEM Avionics system overview General description The Avionics system test mode produces test signals which simulate the ground transmissions of VHF Omnidirectional Range (VOR) air navigation beacons, Instrument Landing System (ILS) aircraft blind landing equipment and Selective Calling (SELCAL) aircraft communication systems.
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AVIONICS SYSTEM The simulated localizer signal B2142 Fig. B-1 ILS screen and menu The simulated localizer signal from the Service Monitor can be set to any of the ILS localizer carrier frequencies between 108 and 112 MHz The carrier is amplitude modulated by signals of 90 Hz and 150 Hz. The Service Monitor ILS display screen and menu gives a graphic and digital readout of the parameters relating to the simulated signal.
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AVIONICS SYSTEM ILS frequency pairing International agreements specify the carrier frequency pairings that can be used for localizer and glideslope frequencies on ILS installations. A look-up table held within the Service Monitor software contains spot frequencies from 108.10 MHz to 111.95 MHz, to provide the localizer signal. A second table, cross-referenced to the first, contains the corresponding glideslope frequencies. (See the ILS frequency pairings table at the end of this chapter.
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AVIONICS SYSTEM VOR In the VOR mode the Test Set simulates the transmissions from VHF OMNIDIRECTIONAL RADIORANGE beacons. These beacons mark the ‘air corridors’ used by aircraft and are situated at strategic locations throughout the world airways network. The transmission from VOR beacons, provide information to determine the direction of the beacon from the receiver installed in the aircraft.
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AVIONICS SYSTEM SELCAL In the SELCAL mode the Test Set simulates the selective calling tones signals used on HF/VHF channels to alert a selected aircraft. The SELCAL system is typically used by commercial aircraft operators for their company communications systems. The codes are regulated and issued by the government aviation authority. The tones are designated in two pairs of two, in the form ‘BK-FB’ or ‘CP-AD’ or ‘BH-FB’. The first pair of tones from the call signal are transmitted simultaneously, i.e.
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AVIONICS SYSTEM Avionics system operation The System mode of operation is activated by pressing the blue [SYSTEM] key. If any of the cellular or trunked radio test systems are fitted, the Cellular/Avionics selection screen will be displayed. See Fig. B-5 Cellular/Avionics selection menu. Pressing one of the Avionics test keys - [SELCAL], [Marker Beacon], [ILS] or [VOR] -will cause the selected test screen to be displayed.
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AVIONICS SYSTEM RF frequency and level The RF frequency and RF level for each of the Avionics modes is set in the same way as for the RX test and Dx test modes. After selecting the parameter to be changed, a new value can be entered using the data input keys or the current value can be adjusted using the variable control. The RF level can be displayed in dBm, in Volt (V, mV or µV) or in dBµV by using the appropriate terminator key.
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AVIONICS SYSTEM Note With the localizer screen displayed, using the FREQ [⇑] or [⇓] increment keys will step the carrier frequency up or down to the next allocated localizer frequency. The corresponding glideslope frequency will be set if the glideslope screen is selected With the glideslope screen displayed, using the FREQ [⇑] or [⇓] increment keys will step up or down the localizer frequency table, but with the glideslope frequency displayed.
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AVIONICS SYSTEM The [Supp Tone] key allows each tone to be suppressed to simulate the Beam Lost’ flag alarm. Repeated presses will step through the following sequence:90 Hz tone suppressed 150 Hz tone suppressed, 90 Hz tone restored 150 Hz tone restored. (neither tone suppressed) Using the [Preset DDM] key A choice of four preset DDM levels is available by pressing the [Preset DDM] key. These are shown in the following table.
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AVIONICS SYSTEM Selecting the marker beacon tone frequency When the [Outer Beacon], [Middle Beacon] or [Inner Beacon] key is pressed, the AF generator will set to 400 Hz, 1.5 kHz or 3 kHz respectively. The tone frequency is shown in the display alongside the appropriate marker designation. The marker tone can be set to a frequency other than one of the three dedicated frequencies.
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AVIONICS SYSTEM Using the Bearing Left and Bearing Right facility The [Bearing Left] and [Bearing Right] keys step the bearing in the selected direction through each 10° point. Using the Bearing To/From facility VOR indicators can show the bearing to and from the beacon being received. Pressing the [Bearing To/From] key cause the indication on the Service Monitor display to change by 180° and show either Bearing to Beacon or Bearing from Beacon as appropriate.
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AVIONICS SYSTEM The test signal is an amplitude modulated RF carrier, set to the required frequency, level and modulation depth. The selected tone sequence can be applied as a continuous reoccurring signal or as a one shot tone burst Setting the RF frequency The RF frequency of the SELCAL test signal can be set to any frequency within the range of the RF generator (400 kHz to 1050 MHz).
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AVIONICS SYSTEM ILS localizer/glideslope pairings The following tables show the pairings of ILS localizer and glideslope transmitter frequencies. The first table is in order of increasing localizer frequency, the second in order of increasing glideslope frequency. ILS frequency pairings. Localizer (MHz) Glideslope (MHz) Glideslope (MHz) Localizer (MHz) 108.10 108.15 108.30 334.70 334.55 334.10 329.15 329.30 329.45 108.95 108.90 110.55 108.35 108.50 108.55 333.95 329.90 329.75 329.60 329.75 329.
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Index A D AC power supply input......................................... 3-8 Acceptance tests ................................................... 5-2 Accessory connector, front panel ......................... 3-6 Accessory port, rear optional............................ 3-101 Accessory socket connections .............................. 2-7 Accessory socket logic ......................................... 2-8 AF GEN OUT,connector...................................... 3-6 AF input coupling option.............
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INDEX G M General Description, Avionics ............................ B-2 General information......................................A-1, 1-1 Getting started ...................................................... 3-9 Glideslope signal ................................................. B-3 Glideslope testing ................................................ B-8 GPIB address ...................................................... 3-14 GPIB connections.................................................
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INDEX Systems testing..................................................... 1-5 Systems mode..............................................1-3, 4-17 Systems testing..................................................... 1-5 R Ranging circuits, measurements ......................... 4-12 Real time clock ................................................... 3-99 Receiver circuits ................................................... 4-9 Receiver test measurements................................
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AEROFLEX INTERNATIONAL LTD. SOFTWARE LICENCE AND WARRANTY This document is an Agreement between the user of this Licensed Software, the Licensee, and Aeroflex International Limited, the Licensor. By opening this Software package or commencing to use the software you accept the terms of this Agreement. If you do not agree to the terms of this Agreement please return the Software package unopened to Aeroflex International Limited or do not use the software. 1.
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AEROFLEX INTERNATIONAL LTD SOFTWARE LICENCE AND WARRANTY 6 The above Warranty does not apply to: 6.1 Defects resulting from software not supplied by Aeroflex, from unauthorised modification or misuse or from operation outside of the specification. 6.2 Third party produced Proprietary Software which Aeroflex may deliver with its products, in such case the third party Software Licence Agreement including its warranty terms shall apply.
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