Codan Radio Communications VT-3A130-S-FSH Transmitter User Manual VHF AM Transmitter Instruction Manual

Codan Radio Communications Transmitter VHF AM Transmitter Instruction Manual

VHF AM Transmitter Instruction Manual

DANIELSELECTRONICS LTD.TMMT-3 RADIO SYSTEMSVHF AM TRANSMITTERINSTRUCTION MANUALVT-3AM118 - 138 MHzCovers Family Model: VT-3A130-SYD410Copyright © 2000 Daniels Electronics Ltd. All rights reserved. No part of this publication may bereproduced, stored in a retrieval system or transmitted in any form or by any means, electronic,mechanical, photocopying, recording or otherwise, without the prior written consent of DanielsElectronics Ltd.DE™ is a registered trademark of Daniels Electronics Ltd. registered in the United States Patent andTrademark Office.Issue: 2 Previous Issue: 1Issue Date: March 2000 Previous Issue Date: May 1997 Daniels Electronics Ltd.Printing Date: March 2000 Victoria, BC.Part No.: IM22-VT3A130 PRINTED IN CANADA
DE DANIELSELECTRONICSii VT-3A130 VHF AM Transmitter Instruction ManualReviewed By:Quality Assurance:Claudia Borman _________________Name Signature DateNOTE:The user's authority to operate this equipment could be revoked through anychanges or modifications not expressly approved by Daniels Electronics Ltd.The design of this equipment is subject to change due to continuousdevelopment. This equipment may incorporate minor changes in detail from theinformation contained in this manual.
DE DANIELSELECTRONICSVT-3A130 VHF AM Transmitter Instruction Manual iiiTABLE OF CONTENTSPage1 GENERAL..................................................................................... 1-11.1 Introduction.............................................................................. 1-11.2 Manual Organization.................................................................... 1-11.3 Performance Specifications ............................................................ 1-21.3.1 Transmitter Specifications........................................................... 1-21.3.2 Audio Specifications................................................................. 1-41.3.3 Physical Specifications .............................................................. 1-42 SYSTEM OVERVIEW....................................................................... 2-12.1 Transmitter Operation................................................................... 2-12.2 Frequency Selection .................................................................... 2-22.2.1 BCD Switch Option.................................................................. 2-22.2.2 Frequency Select Handle Option. .................................................. 2-22.3 Transmitter Assembly and Alignment ................................................ 2-32.3.1 Complete Transmitter Alignment................................................... 2-32.3.2 Output Power Adjustment........................................................... 2-32.4 Recommended Test Equipment List .................................................. 2-42.5 Repair Note .............................................................................. 2-42.6 Printed Circuitboard Numbering Convention........................................ 2-43 ILLUSTRATIONS ........................................................................... 3-13.1 MT-3 Transmitter Front Panel......................................................... 3-13.2 MT-3 Transmitter Case - Exploded View ............................................ 3-24 REVISION HISTORY ....................................................................... 4-1MODULE MANUALSMT-3 AM Transmitter Main Board Instruction Manual ............IM22-MT3AMTXMNVT-3A130 Amplifier Instruction Manual .............................IM22-VT3A130AMPEnhanced AM/FM Synthesizer Instruction Manual .......................... IM10-OS3AHVHF AM Transmitter Channel Designation Tables ................... IM12VRT3A130CTFrequency Select Handle Instruction Manual....................................IM12-FSH3
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DE DANIELSELECTRONICSVT-3A130 VHF AM Transmitter Instruction Manual 1-11 GENERAL1.1 IntroductionThe VT-3A130 Transmitter is a synthesized multichannel AM transmitter designed to interface withthe MT-3 Repeater Systems, while still maintaining MT-2 system compatibility. Both MT-3systems are characterized by dependable low maintenance performance under the most severeenvironmental conditions. All performance measurements comply with Industry Canada (IC)Standard Specification RSS 119 and 140, as well as the Federal Communications CommissionPart 87 for AM equipment. In addition, all units are burnt-in for 24 hours and are accompanied bya complete test report.The VT-3A130 Transmitter operates in the 118 - 138 MHz aviation band. The transmitter'sfrequency stability is controlled by an OST-3A128 Synthesizer. The synthesizer module can beprogrammed to have up to 16 channels. A channel programmer can preprogram the first 15channels; channel 16 can be programmed from the front panel and channel 1 can be programmedby the four BCD switches located on the MT-3 AM Transmitter Main Board.1.2 Manual OrganizationThe organization of this manual reflects the modular makeup of the VT-3 product line. Eachmodule is fully described within its respective submanual, all of which are contained within thisdocument. In general, each submanual contains:1. A functional description and specification summary.2. A detailed technical description (Theory of Operation).3. Assembly, setup and alignment procedures relevant to that particular module.* Note * Material presented in a given "sub-manual" may include information related to othermodule versions not directly applicable to the VT-3A130 transmitter family. The OS-3Hsynthesizer module is a prime example, having family members covering from 29 to 512 MHz.
DE DANIELSELECTRONICS1-2 VT-3A130 VHF AM Transmitter Instruction ManualThe following sub-manuals are contained within this document cluster:AM Transmitter Manua l: This manual provides an overview of the complete transmitter, manualorganization and assembly in terms of the other modules.MT-3AM Transmitter Main Board: This manual pertains to the AM audio processor module,transmitter Main Board and Front Panel Board. Most of the user selectable options are accessedwithin the Transmitter Main Board module, including channel selection. Since all externalconnections (including power and signal lines) are made to the Transmitter Main Board, most ofthe material pertaining to transmitter operation and installation is found here.VT-3A130 Amplifier: The amplifier module provides the final stages of RF power amplificationand harmonic filtering for the transmitter. This manual is intended primarily as a reference forfrequency changes since the amplifier module is adjusted at the factory.Enhanced AM/FM Synthesizer: This manual provides information on alignment and operation ofthe Enhanced Synthesizer Module. Channel selection is described in the 'Transmitter Main Board”Manual.VHF AM Transmitter / Receiver Channel Designation Tables: This manual relates operatingfrequency to the transmitter channel number (see section 2.1).Frequency Select Handle Instruction Manual: This manual provides information on how toprogram the synthesizer channels from the front panel.1.3 Performance Specifications1.3.1 Transmitter SpecificationsType: MT-3 Series TransmitterFamily: VT-3A130Compatibility: MT-2 Series and MT-3 Series Radio SystemsFrequency Range: 118 - 138 MHzRF Power Output: 1.0 - 4.0 Watts adjustable (carrier only)Frequency Generation: Synthesized (internal plug-in module)Channel Spacing: 25 kHz (8.333 kHz)System Impedance: 50 Ω; Type N (Standard)
DE DANIELSELECTRONICSVT-3A130 VHF AM Transmitter Instruction Manual 1-3Duty Cycle: 100%; Continuous operation from -30°C to +60°C. (- 40°COptional)Spurious and Harmonic Emissions: More than 90 dB below carrierKey-On/Key-off Spectral Mask Transients are at least 80 dBc below for frequencies±400 kHz from carrier.Input VSWR: 2.8:1 Maximum.Load VSWR tolerance: Z load = 20:1:Modulation: 6K00A3 Amplitude ModulationTransmitted Noise More than 45 dBc below carrierOperating Temperature Range: -30˚C to +60˚C, optional - 40˚C temperature test.Operating Humidity: 95% Relative Humidity (Non-condensing) at+25°COperating Voltage: +13.8Vdc Nominal (range +10 Vdc to +17 Vdc)Active Current: +13.8 Vdc supply less than 1.5 A at Pout = 4 WattsChannel Selection: In 25kHz (8.333 kHz) increments selected by two frontpanel buttons. Preset capability for 15 channels selectablethrough external control.Frequency Stability: Standard: ±1ppm -30°C to +60°C (optional -40˚C)Standby Current (9.5Vdc) and Rise time: Typ. 20 mA/30ms MODE 1(Also see Transmitter Typ. 17 mA/50ms MODE 2Main Board Specification)FCC Type Approval: TBADOC Type Approval: TBAFront Panel Control: One 3 position switch• NORM (repeat mode)• OFF• KEY TXPTT Activation: • Active to ground with time-out timer• Active to ground without time-out timer• Microphone activated without time-out timer• Front Panel switch (KEYED) without time-outtimer, (NORM) with or without time-out-timer.PTT Time-Out-Timer: Selectable 1 seconds to 8 hours. (factory set 5min)
DE DANIELSELECTRONICS1-4 VT-3A130 VHF AM Transmitter Instruction Manual1.3.2 Audio SpecificationsAudio Input: -25 to 0 dBm into a 600Ω balanced loadAudio Response: Flat audio; +1/-3 dB: 300 Hz - 3 kHzAudio Distortion: Less than 3% -40˚C to +60˚C at 30% modulationLess than 5% -40˚C to +60˚C at 90% modulation1.3.3 Physical SpecificationsPhysical Dimensions: Width: Height: Depth:7.1 cm (2.8 in) 12.8 cm (5.05 in) 19 cm (7.5 in)Module Weight: 1.4 kg (3.0 lb.)Corrosion Prevention: Anodized aluminum construction. Stainless steel hardware.Selectively conformal coated glass epoxy 2 and 4 layerprinted circuitboards. Gold plated module connectors.Module Design: Compact Eurostandard modular design. Plug-in modulesmate with Daniels standard M3 repeater subrack. Subracks /modules comply with IEEE 1101, DIN 41494 and IEC 297-3 (mechanical size / modular arrangement).External Connections: RF Connection: type N connector located on the transmittermodule front panel. Motherboard Connections (Audio,Power, and Control) are made through a 48 pin, gold plated,type F connector on the rear of the transmitter module. Userconnection made through mated "mother board" assembly ofthe repeater subrack. Type F standard connector complieswith DIN 41612 Level 2 (200 mating cycles, 4 day 10 ppmSO2 gas test with no functional impairment and no change incontact resistance).
DE DANIELSELECTRONICSVT-3A130 VHF AM Transmitter Instruction Manual 2-12 SYSTEM OVERVIEW2.1 Transmitter OperationSeveral modules are integrated by the VT-3A130 Transmitter Main Board to provide the completetransmitter. The Front Panel Board and AM Audio Processor are soldered directly to theTransmitter Main Board and are treated collectively in the Transmitter Main Board Manual whilethe Power Amplifier and and the Frequency Synthesizer plug into the Transmitter Main Board andcan be changed with minimal effort. Circuitry and jumpers on the Transmitter Main Board controlthe operation of all modules and the operation of the transmitter, overall. Technical details and acomplete description of transmitter operation can be found in the Transmitter Main Board Manual.The VT-3A130 transmitter requires two power supplies; a regulated + 9.5 Vdc supply and+ 13.8 Vdc supply, the later of which is connected only to the Amplifier Module. The (nominally)+13.8 Vdc supply's range is +10.0 Vdc to +17.0 Vdc. The current drawn from the 9.5 Vdc supplyis (see MODE 1-2) while the current drawn from the +13.8 Vdc supply (while transmitting at therated power) varies between 500 ma to 1500mA with temperature, operating frequency and powersupply voltage. The current drawn by the 13.8Vdc line should not exceed 1500mA. The currentdrawn by the transmitter in its quiescent state depends on what modules are enabled during theinactive (PTT off) state. This aspect of transmitter operation is controlled by jumper settings on thetransmitter Main Board (refer to the Transmitter Main Board Manual). The minimum quiescentcurrent is under 17ma and occurs when the Audio Processor is disabled while the transmitter isoff. If Synthesizer and Audio Processor operation is maintained continuously, the quiescentcurrent is approximately 80 ma.The front panel depicted in Section 3.1 bears a DPDT toggle switch (mounted on the Front PanelBoard; see the Transmitter Main Board Manual) which controls the operation of the VT-3A130Transmitter. When in the 'OFF' position, the transmitter is turned off; however, the 13.8 Vdcremains on the Transmitter Main Board terminals and on the Amplifier module. When in the'KEYED' position, +9.5 Vdc is supplied to the transmitter circuitry and the transmitter iscontinuously transmitting. When this switch is in the 'NORM' position +9.5Vdc is supplied to thetransmitter circuitry although the transmitter remains quiescent until keyed from one of severalPush-To-Talk (hereafter PTT) inputs. The red indicator LED is illuminated during transmitting.Microphone, RF output and optional reference input are mounted on the front panel; power andother signal connections are provided by a type 'F' connector at the rear of Transmitter MainBoard. Details on their function can be found in the Transmitter Main Board Manual.
DE DANIELSELECTRONICS2-2 VT-3A130VHF AM Transmitter Instruction Manual2.2 Frequency Selection2.2.1 BCD Switch Option.For operation in this mode, the external channel select must be set to channel 01. Transmitterchannel selection is achieved by setting a decimal number on four BCD frequency select switches,FSW1 through FSW4. The switch settings are scanned by the synthesizer module when thetransmitter is first powered up, and the desired frequency is generated. Refer to the followingequations or the channel designation tables for simplified channel number and frequencyinformation.For VT-3A130 model 118-138 MHz:• 8.333 kHz channel increments (BCD settings from 0000 to 2400):CHNL#= Tx 118 MHz8.333 kHzfrequency −orTx = CHNL# .333 kHz 118 MHzfrequency ×[]+82.2.2 Frequency Select Handle Option.For operation in this mode, the external channel select must be set to channel 16. Transmitterchannel selection is achieved by pushing the buttons Ø (frequency increase) Œ and (frequencydecrease) on the Frequency Select Handle. The Frequency Select Handle is located on the FrontPanel. The user interface consists of an 8 digit display and 3 pushbuttons. On power up or keypress, the synthesizer is interrogated for the current channel number and channel frequencies. Thisinformation is used to generate the display, and update the synthesizer. The module communicateswith the synthesizer using a standard 2 wire serial interface (9600 Baud, 8 bits, no parity, 1 stopbit). The command protocols are simple ASCII, both to and from the synthesizer.The frequency value and the channel are displayed on the Front Panel for several seconds only, inorder to conserve the power. Another dedicated line allows the handle to temporarily wake up thesynthesizer if it has been powered down. (This is currently only used on the transmitters)For detailed information about changing frequency, see the "Frequency Select Handle InstructionManual".
DE DANIELSELECTRONICSVT-3A130 VHF AM Transmitter Instruction Manual 2-32.3 Transmitter Assembly and AlignmentAll modules are mounted on the Transmitter Main Board, which then forms a single assembly. Anenclosure is formed by an extruded aluminum shell that slides over the Transmitter Main Board (asillustrated in section 3.2). This shell also serves as a heatsink to remove heat from the Amplifiermodule and for this reason, it is important that the four screws that bond the shell to the amplifiermodule (Screws B in Section (3-2)) be installed before prolonged operation of the transmitter.Moreover, the surface of the Amplifier module that contacts the shell should be clean and free offoreign material. The enclosure is completed by the installation of front and rear plates, which arefastened to the Transmitter Main Board (see Transmitter Main Board Manual for parts lists).Transmitter alignment is performed on a module by module basis and detailed steps are provided inthe respective manuals. Alignment is simplified by using a SR-3 Subrack, SM-3 System Monitor,and RF extended cable to provide transmitter power and signal interconnection. Alternatively,+9.5 Vdc and +13.8 Vdc, as well as any required test signals may be applied directly to theindividual modules. Refer to the corresponding manuals for details.2.3.1 Complete Transmitter AlignmentA complete Transmitter Alignment is performed at the factory and should not be required undernormal circumstances. This operation requires that all the transmitter modules be aligned on a permodule basis in the following order. Sequence Module Manual Reference (1) Transmitter Main Board section 2.2 of Transmitter Main Board(2) Synthesizer Module Synthesizer Module(3) Amplifier Amplifier(4) Audio Processor Transmitter Main Board2.3.2 Output Power AdjustmentThe RF power output of the amplifier is to set to its rated value of 4.0Watts +/- 1dB at the factoryin the middle of the frequency range 118 MHz - 138 MHz. This should not require adjustmentunder normal circumstances. However, should it be necessary to correct the output power, theOutput Power Adjustment, which is described in the Amplifier Manual can be adjustedaccordingly.
DE DANIELSELECTRONICS2-4 VT-3A130VHF AM Transmitter Instruction Manual2.4 Recommended Test Equipment ListAlignment of the transmitter requires the following test equipment or its equivalent.Dual Power Supply: Regulated +9.5 Vdc at 2 ARegulated +13.8 Vdc at 2 A - Topward TPS-4000Oscilloscope / Multimeter: Fluke 97 ScopemeterCurrent Meter: Fluke 75 multimeterRadio communications test set: Marconi Instruments 2955RVSWR 3:1 mismatch load: JFW 50T-035-3.0:1Alignment Tool: Johanson 8766It is recommended that the radio communications test set be frequency locked to an externalreference (WWVH, GPS, Loran C) so that the high stability oscillator may be accurately set towithin its ±1 ppm frequency tolerance.2.5 Repair NoteThe VT-3A130 Transmitter is mainly made up of surface mount devices which should not beremoved or replaced using an ordinary soldering iron. Removal and replacement of surface mountcomponents should be performed only with specifically designed surface mount rework and repairstations complete with ElectroStatic Dissipative (ESD) protection.When removing Surface Mount Solder Jumpers, it is recommended to use solder braid in place ofmanual vacuum type disordering tools when removing jumpers. This will help prevent damage tothe circuitboards.2.6 Printed Circuitboard Numbering ConventionTo ease troubleshooting and maintenance procedures, Daniels Electronics Limited has adopted aprinted circuitboard (PCB) numbering convention in which the last two digits of the circuitboardnumber represent the circuitboard version. For example:• PCB number 43-9120 10 indicates circuitboard version 1.0;• PCB number 50002- 02 indicates circuitboard version 2.0.All PCB's manufactured by Daniels Electronics are identified by one of the above conventions.
DE DANIELSELECTRONICSVT-3A130 VHF AM Transmitter Instruction Manual 3-13 ILLUSTRATIONS3.1 MT-3 Transmitter Front PanelMADE IN CANADAVT-3A130-SYD410MADE IN CANADAMADE IN CANADAAMTXM1BON / OFF SWITCHTYPE N RF OUTPUT JACKSMA REFERENCEINPUT JACKTRANSMIT INDICATOR LEDTRANSMITTER MODEL IDENTIFIERMICROPHONECONNECTORTRANSMITTERTXREFERENCEINPUTOFFNORMKEY TXMICRF OUTFREQUENCYDECREASE BUTTONFREQUENCY INCREASE BUTTONOPTIONS BUTTON*Daniels Electronics Ltd
DE DANIELSELECTRONICS3-2 VT-3A130VHF AM Transmitter Instruction Manual3.2 MT-3 Transmitter Case - Exploded View3 FINGER GASKET (2)Instructions1. Remove the four screws (A) in the Front panel.2. Remove the four screws (B) on the side of the Transmitter Case.AABBBBAMTXM2AAA
DE DANIELSELECTRONICSVT-3A130 VHF AM Transmitter Instruction Manual 4-14 REVISION HISTORYISSUE DATE DESCRIPTION AND (REASON) 1 May 97 •Issue 1.2 Mar 00 •The transmitter is now capable of working over the whole AM frequencyband (118 –138 MHz) without being re-tuned.
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