Kenwood TK-780 Service Manual
  1. Manuals
  2. Brands
  3. Kenwood Manuals
  4. Transceiver
  5. TK-780 series
  6. Service manual
Kenwood TK-780 Service Manual

Kenwood TK-780 Service Manual

Hide thumbs Also See for TK-780:
Table of Contents

Advertisement

Quick Links

See also: Instruction Manual
Document Copyrights
Copyright 2006 by Kenwood Corporation. All rights reserved.
No part of this manual may be reproduced, translated, distributed, or transmitted in any
form or by any means, electronic, mechanical, photocopying, recording, or otherwise, for
any purpose without the prior written permission of Kenwood.
Disclaimer
While every precaution has been taken in the preparation of this manual, Kenwood
assumes no responsibility for errors or omissions. Neither is any liability assumed for
damages resulting from the use of the information contained herein. Kenwood reserves
the right to make changes to any products herein at any time for improvement purposes.

Advertisement

Table of Contents
loading

Related Manuals for Kenwood TK-780

Summary of Contents for Kenwood TK-780

  • Page 1 Kenwood. Disclaimer While every precaution has been taken in the preparation of this manual, Kenwood assumes no responsibility for errors or omissions. Neither is any liability assumed for damages resulting from the use of the information contained herein. Kenwood reserves...

  • Page 2: Table Of Contents

    VHF FM TRANSCEIVER TK-780 SERVICE MANUAL E version © 2000-4 PRINTED IN JAPAN B51-8523-00 ( N ) 553 Panel assy Cabinet (Upper) Key top (A62-0642-03) (A01-2165-13) (K29-5422-02) CONTENTS GENERAL ..............2 ADJUSTMENT ............45 OPERATING FEATURES ......... 3 PC BOARD VIEWS REALIGNMENT ............

  • Page 3: General

    TK-780 GENERAL 2-2. Testing INTRODUCTION The radio should be tested complete with all cabling and SCOPE OF THIS MANUAL accessories as they will be connected in the final installa- This manual is intended for use by experienced techni- tion. Transmitter frequency, deviation, and power output...
  • Page 4 4. INSTALLATION PLANNING – CONTROL STATIONS 1. Operation Features 4-1. Antenna system The TK-780 is a VHF FM radio designed in both 5-tone Control station. The antenna system selection depends model and DTMF/2-tone/DMS model. The programmable on many factors and is beyond the scope of this manual.

  • Page 5: Operating Features

    TK-780 OPERATING FEATURES 2-2. Programmable Keys Channel Name The FPU (KPG-60D) enables programmable keys to se- Press this key to switch between the "Channel name" lect the following functions. and "Grp #/Ch #" for the display. If no channel name is pro-...
  • Page 6 TK-780 OPERATING FEATURES Group Up/Down Operator Selectable Tone When this key is pressed each time, the group number to When this key is pressed, the "OST" appears and encode/ be selected is increased/decreased and repeats if held for decode QT/DQT is switched to the OST tone pair. If one second or longer.
  • Page 7 TK-780 OPERATING FEATURES Receive Entry (5-tone) Selcall List Press [Receive entry] key to enter the desired Selcall Press [Selcall list] key to enter Selcall list mode. code you want to receive. This function can be activated • 5-tone only when "RX address" is set to the channel and "selectable receive digit"...
  • Page 8 TK-780 OPERATING FEATURES Status Entry (5-tone) Function Table It allows the operator to input the status and transmit it to Function DTMF/2-tone/DMS 5-tone the base station. None Both TX address and "Selectable status digit" must be Auto dial programmed to perform the operation. Press [Status entry] Auto dial programming key to access Status entry mode.

  • Page 9: Scan Operating

    TK-780 OPERATING FEATURES 2-3. Front Panel Displays and Indicators Handset indicator Sub display This icon is not used this transceiver. Displays the system, channel and group numbers. Also MAIL indicator displays various functions, such as TA. Flashes when a status message (5-tone or DMS) is re- P (Priority) indicator ceived.
  • Page 10 TK-780 OPERATING FEATURES Scan channel types Scan end 1) Priority channel is the most important channel for the When you reactivate the key programmed to the scan scan, and always detects a signal during scan and when function during scan mode, the scan ends.
  • Page 11 TK-780 OPERATING FEATURES Com port Radio password • Com 0 When the password is set in the transceiver, user can not use the transceiver unless enter the correct password. This function selects the external serila port function at This code can be up to 6 digits from 0 to 9 and input with the microphone jack (TXD/RXD).
  • Page 12 It is possible to use individual call, group call, stun, kill. The Alphanumeric Two-way Paging Function (DMS) is a Stun and kill are used with DTMF only. Kenwood proprietary protocol. It enables a variety of paging If the option signalling matches, a predetermined action functions.
  • Page 13 TK-780 OPERATING FEATURES Selective Call (SELCALL) Short Messase (Optional) This is a voice call to a particular individual or group of A maximum of 48 characters can be sent (External equip- stations. ment is required). Received Short Messages will be dis- played in the same manner as a Status Message.
  • Page 14 2) MAP HEADER KW1 ($PKLDS) Data TX Modulation Delay Time is the amount of time This is a Kenwood original sentence which consists of from the beginning of transmission to the beginning of a “$GPGLL + Fleet + ID + Status”. This item should be set data modulation.
  • Page 15 TK-780 OPERATING FEATURES Monitor Function Selectable Selcall Digit You can select either QT/DQT or 5-tone decoding to be Select the check box to change selcall code (maximum 8 canceled when [Monitor] or [Monitor momentary] key is digits) manually when transmitting encode code. You can- pressed.

  • Page 16: Audible User Feedback Tones

    TK-780 OPERATING FEATURES Decode Code 8. Audible User Feedback Tones When "Special setting" is disabled, you can select the The transceiver outputs various combinations of tones to decode code setting from #1 to #8. The transceiver tries to notify the user of the transceiver operating state. The main decode the selected decode code setting (maximum 8 dif- tones are listed below.

  • Page 17: Realignment

    PC test mode Used to check the radio using the PC. • Change the TK-780 to PC mode, then attach the interface This feature is included in the FPU. cable.

  • Page 18: Self Programming Mode

    3. Set the firmware to be updated by File name item. it has been disabled with the KPG-60D. 4. Turn the TK-780 Power ON with the [A] switch held down. Hold the switch down until the display changes to "PROG 57600". When "PROG 57600" appears, release your finger from the switch.
  • Page 19 TK-780 REALIGNMENT 7-2. Channel Setting Mode 7-3. Flow Chart Each channel can be setup in its action mode by using Self programming the panel keys. mode • Pressing [ ] while "SELF PROG" is displayed will change to channel setting mode.

  • Page 20: Installation

    TK-780 INSTALLATION 1-2. KCT-19 Accessory Port Function 1. Accessory Connection Cable No. (A) No. (B,C,D,E) Name Function Note (KCT-19 : Option) External hook input The KCT-19 is an accessory connection cable for con- Microphone ground necting external equipment. The connector has 15 pins and Speaker audio mute input the necessary signal lines are selected for use.
  • Page 21 TK-780 INSTALLATION 1-3. Data Equipment Connection 2. Accessory Terminal (TX-RX Unit) The jumpers must be set to either one for each function. 2-1. External Connector Accessory Terminal Method Otherwise, the radio will not work properly. Connector Function ME/AM name R12 (0Ω) R167 (0Ω) Function / Default O Detect signal output.
  • Page 22 TK-780 INSTALLATION Schematic diagram PC board view Connector Function name Name I/O Function Name Unit Serial data input 1. "Com1" port CODE3 Option code 1 (for voice TX-RX must be select "DATA"/"GPS" scrambler code 3) function in the KPG-60D. CODE4...
  • Page 23 2. Set jumper resistors (0Ω) R151 and R152 of the TX-RX 5-2. Voice Scrambler Board Connection unit (A/2) as shown in Table 1. • Modification 1. Remove the upper half of the case of the TK-780. Operation when KCT-18 is connected R151 R152 2.
  • Page 24 TK-780 INSTALLATION Scrambler board TK-780 6. PA/HA Unit (KAP-1 : Option) Code 4 (C4) (TX-RX PCB) 6-1. Installing the KAP-1 in the Transceiver Code 3 (C3) (TX-RX PCB) The Horn Alert (max. 2A drive) and Public Address func- Code 2 (C2)
  • Page 25 TK-780 INSTALLATION 7. Fitting the Control Panel Upside Down The TK-780/780H control panel can be fitted upside down, so the transceiver can be mounted with its internal speaker (in the upper half of the case) facing down in your car.

  • Page 26: External Speaker

    TK-780 INSTALLATION 8-2. KES-4 : Option 6. Rotate the control panel 180 degrees and mount it on the transceiver. Refit the two halves of the case to complete The KES-4 is an external speaker used with the acces- installation. (Fig. 11) sory connection cable.

  • Page 27: Circuit Description

    TK-780 CIRCUIT DESCRIPTION an LPF and an attenuator to eliminate unwanted harmonics Frequency Configuration components and implement the optimum input level to the The TX-RX unit incorporates a VCO, based on a fractional mixer, then enters IC202. A DBM is used as a mixer to N type PLL synthesizer system, that allows a channel step achieve a high potential.
  • Page 28 VCO/PLL Circuit the D/A converter (IC5). The AFO output level is adjusted by The TK-780 has a VCO for the transmitter and a VCO for the D/A converter. The signal output from the D/A converter the receiver in a sub-unit (A-1). They are housed in a solid...
  • Page 29 TK-780 CIRCUIT DESCRIPTION Unlock Circuit Q17 turns the PC signal on or off using 8T so that the circuit works only during transmission. With stability at low During reception, the TR signal goes high, the KEY signal power in mind, Q29 turns off to optimize the detection volt- goes low, and Q10 turns on.
  • Page 30 Key Matrix Circuit through two low-pass filters of IC501, goes to LSDI of the The TK-780 front panel has ten keys. Each of them is CPU (IC511) to decode QT, DQT. The DTMF signal is de- connected to a cross point of a matrix of the KEY1 to KEY7 coded by a dedicated IC (IC507) and the resulting signal is ports of the microprocessor.
  • Page 31 TK-780 CIRCUIT DESCRIPTION Horn Control Power Supply Circuit The horn switch, consisting of Q4, Q5, and Q6, controls When the POWER switch on the control unit is pressed, the horn relay. It is supplied by the dealer to provide the the PSW signal goes low.

  • Page 32: Semiconductor Data

    TK-780 SEMICONDUCTOR DATA Microprocessor : 30620M8-394GP (TX-RX Unit IC511) Terminal function Pin No. Name Function Pin No. Name Function LSDOUT Low speed data output. PLL IC data strobe output. HSDOUT High speed data output. Flash memory chip enable. HSDIN High speed data input.
  • Page 33 TK-780 SEMICONDUCTOR DATA / DESCRIPTION OF COMPONENTS Terminal function (TX-RX unit IC8) DESCRIPTION OF COMPONENTS Pin No. Port Name Function Strobe TX-RX Unit (X57-6142-70) (A/2) DATA Ref. No. Use / Function Operation / Condition Clock DC amp FC, TCXO control Audio mute 1.

  • Page 34: Description Of Components

    TK-780 DESCRIPTION OF COMPONENTS Ref. No. Use / Function Operation / Condition Ref. No. Use / Function Operation / Condition W/N switch Wide time on IC504 Audio processor Compander, MIC amplifier, ALC, TOF switch Q22 on time on Modem, AF filter, IDC Inverter Power switch "L"...

  • Page 35: Parts List

    TK-780 PARTS LIST CAPACITORS CC 45 TH 1H 220 J • Capacitor value Color* CC45 010 = 1pF 0 = 22pF 100 = 10pF 1 = Type … ceramic, electrolytic, etc. 4 = Voltage rating Multiplier 101 = 100pF 2 = Shape … round, square, ect.
  • Page 36 TK-780 PARTS LIST New Parts. indicates safety critical components. L : Scandinavia K : USA P : Canada Parts without Parts No. are not supplied. Y : PX (Far East, Hawaii) T : England E : Europe Les articles non mentionnes dans le Parts No. ne sont pas fournis.
  • Page 37 TK-780 PARTS LIST TX-RX UNIT (X57-6142-70) Desti- Desti- Ref. No. Address Parts No. Description Ref. No. Address Parts No. Description parts nation parts nation C92-0044-05 CHIP-ELE 47UF 10WV C149 CC73FCH1H020B CHIP C 2.0PF CK73GB1H102K CHIP C 1000PF C150 CK73GB1H221K CHIP C...
  • Page 38 TK-780 PARTS LIST TX-RX UNIT (X57-6142-70) Desti- Desti- Ref. No. Address Parts No. Description Ref. No. Address Parts No. Description parts nation parts nation C262-264 CC73GCH1H820J CHIP C 82PF C520 CC73GCH1H221J CHIP C 220PF C265 C93-0564-05 CHIP C 22PF C521,522...
  • Page 39 TK-780 PARTS LIST TX-RX UNIT (X57-6142-70) Desti- Desti- Ref. No. Address Parts No. Description Ref. No. Address Parts No. Description parts nation parts nation C603 CK73GB1C104K CHIP C 0.10UF L215 L34-0742-05 AIR-CORE COIL C604 C92-0566-05 CHIP-TAN 10UF 6.3WV L216 L34-4482-05...
  • Page 40 TK-780 PARTS LIST TX-RX UNIT (X57-6142-70) Desti- Desti- Ref. No. Address Parts No. Description Ref. No. Address Parts No. Description parts nation parts nation RK73GB1J122J CHIP R 1.2K 1/16W R141 RK73GB1J104J CHIP R 100K 1/16W RK73GB1J102J CHIP R 1.0K 1/16W...
  • Page 41 TK-780 PARTS LIST TX-RX UNIT (X57-6142-70) Desti- Desti- Ref. No. Address Parts No. Description Ref. No. Address Parts No. Description parts nation parts nation R248 RK73GB1J182J CHIP R 1.8K 1/16W R532 RK73GB1J394J CHIP R 390K 1/16W R250 R92-0670-05 CHIP R...
  • Page 42 TK-780 PARTS LIST TX-RX UNIT (X57-6142-70) Desti- Desti- Ref. No. Address Parts No. Description Ref. No. Address Parts No. Description parts nation parts nation R631 R92-1368-05 CHIP R 0 OHM D12-14 HSB123 DIODE R632 RK73HB1J102J CHIP R 1.0K 1/16W DAN235E...
  • Page 43 TK-780 PARTS LIST TX-RX UNIT (X57-6142-70) PLL/VCO (X58-4712-70) Desti- Desti- Ref. No. Address Parts No. Description Ref. No. Address Parts No. Description parts nation parts nation IC710,711 TA75S01F IC (OP AMP) C120 CC73GCH1HR75B CHIP C 0.75PF 2SK1824 C121 CK73GB1H102K CHIP C...

  • Page 44: Exploded View

    TK-780 EXPLODED VIEW Parts with the exploded numbers larger than 700 are not supplied.

  • Page 45: Packing

    TK-780 PACKING 36 Protection bag 37 Protection bag (H25-0103-04) (H25-0720-04) 5 Cap (B09-0235-05) 10 DC cord (E30-3339-05) 21 Fuse (F51-0016-05) 40 Bracket (J29-0627-23) 35 Inner packing case (H12-1391-03) 44 Screw set (N99-0395-05) 34 Polystyrene foamed fixture (B) (H10-6619-12) 7 Instruction manual...

  • Page 46: Adjustment

    TK-780 ADJUSTMENT Frequency and Signalling Test Mode The set has been adjusted for the frequencies shown in Test Mode Operating Features the following table. When required, re-adjust them follow- This transceiver has a test mode. To enter test mode, ing the adjustment procedure to obtain the frequencies you press [B] key and turn power on.
  • Page 47 TK-780 ADJUSTMENT • Tuning flow Press [A], now in tuning mode. Use [C] button to write tuning data through tuning modes, and [Channel Up/Down] to adjust tuning requirements (1 to 256 appears on LCD). FREQ xxx Use [D] button to select the adjustment item through tun- ing modes.
  • Page 48 TK-780 ADJUSTMENT Test Equipment Required for Alignment Test Equipment Major Specifications 1. Standard Signal Generator Frequency Range 136 to 174MHz (SSG) Modulation Frequency modulation and external modulation Output –127dBm/0.1µV to greater than –7dBm/100mV 2. Power Meter Input Impedance 50Ω Operation Frequency...
  • Page 49 Repair Jig (Chassis) • EEPROM Use jig (Part No. : A10-4010-02) for repairing the TK-780. The tuning data (Deviation, Squelch, etc.) for the The jig facilitates the voltage check when the voltage on the EEPROM, is stored in memory. When parts are changed, component side TX-RX unit is checked during repairs.
  • Page 50 TK-780 ADJUSTMENT Receiver Section Measurement Adjustment Item Condition Specifications/Remarks Test- Unit Terminal Unit Parts Method equipment 1. Discriminator 1) Set test mode Rear TX-RX L6 AF output voltage CH : CH1 - Sig1 panel (A/2) maximum. SSG output : –53dBm AF VTVM AF : 1.4V/4Ω...
  • Page 51 TK-780 ADJUSTMENT Measurement Adjustment Item Condition Specifications/Remarks Test- Unit Terminal Unit Parts Method equipment 5. Squelch 1) Set test mode Rear Squelch must be (Tight) Select "nL SQLT" in tuning mode. panel closed once. SSG freq' : 146.050MHz AF VTVM Then adjust for SSG output : –109dBm...
  • Page 52 TK-780 ADJUSTMENT Transmitter Section Measurement Adjustment Item Condition Specifications/Remarks Test- Unit Terminal Unit Parts Method equipment 1. Frequency 1) Set test mode Power meter Rear Check 160.100MHz±100Hz Select "FREQ" in tuning mode. F. counter panel PTT : ON ± 0.5W 2.
  • Page 53 TK-780 ADJUSTMENT Measurement Adjustment Item Condition Specifications/Remarks Test- Unit Terminal Unit Parts Method equipment 7. Maximum 1) Set test mode Power meter Rear 4.1kHz (Wide) +0Hz/–50Hz deviation Connect AG to the MIC Deviation panel 3.3kHz (Semi-wide) (Wide/Semi-wide/Narrow) terminal. meter 2.05kHz (Narrow) Select "MAX"...
  • Page 54 TK-780 ADJUSTMENT Measurement Adjustment Item Condition Specifications/Remarks Test- Unit Terminal Unit Parts Method equipment ± 0.2kHz (Wide/Semi-wide) 11. DTMF 1) Set test mode Power meter Rear 3.0kHz (Wide) ± 0.1kHz (Narrow) deviation Select "n DTMF" in tuning mode. Deviation panel 2.4kHz (Semi-wide)

  • Page 55: Pc Board Views

    TK-780 PC BOARD VIEWS PLL/VCO (X58-4712-70) Component side view J72-0732-02 CN101 L110 L103 R101 C122 L105 C134 C104 R105 L106 C136 R116 Q105 C127 R107 Q106 C138 R108 Q101 R109 C114 R103 C135 C129 Q104 C111 C125 C110 C113 L104...

  • Page 56: Tx-Rx Unit (X57-6142-70) (A/2)

    TK-780 PC BOARD VIEW TX-RX UNIT (X57-6142-70) (A/2) Component side view Ref. No. Address Ref. No. Address Ref. No. Address Ref. No. Address Ref. No. Address Q403 IC10 IC11 D206 IC14 Q300 D207 Component side IC400 IC202 Q301 D208 Pattern 1...

  • Page 57: Tx-Rx Unit (X57-6142-70) (B/2)

    TK-780 PC BOARD VIEW TX-RX UNIT (X57-6142-70) (A/2) Foil side view Ref. No. Address Ref. No. Address Ref. No. Address Ref. No. Address Ref. No. Address Ref. No. Address Ref. No. Address IC13 Q26 10C IC15 IC201 6M Q15 12K...
  • Page 58 TK-780 PC BOARD VIEW Ref. No. Address Ref. No. Address Ref. No. Address Ref. No. Address Ref. No. Address Ref. No. Address Ref. No. Address Ref. No. Address TX-RX UNIT (X57-6142-70) (A/2) Component side view + Foil side IC13 IC14...
  • Page 59 TK-780 PC BOARD VIEWS TX-RX UNIT (X57-6142-70) (B/2) Component side view J72-0724-12 B/2 D512 R514 D517 R710 C712 R517 R510 C527 C710 C518 C583 R526 R713 L507 IC710 R525 R682 IC502 C524 R572 D511 IC501 IC508 C592 R531 R714 R502...
  • Page 60 TK-780 PC BOARD VIEW TX-RX UNIT (X57-6142-70) (B/2) Component side view + Foil side J72-0724-12 B/2 D512 R520 R514 D517 R710 C607 C712 R517 MPTT C516 R518 R510 C515 C527 C710 C518 C583 R525 RXAO R680 R521 R526 R713 L507...

  • Page 61: Schematic Diagram

    TK-780 SCHEMATIC DIAGRAM Note : Components marked with a dot (·) are parts of patterun 1.
  • Page 62 TK-780 Note : Components marked with a dot (·) are parts of patterun 1. SCHEMATIC DIAGRAM...

  • Page 63: Block Diagram

    TK-780 TK-780 TK-780 BLOCK DIAGRAM...

  • Page 64: Level Diagram

    TK-780 TK-780 LEVEL DIAGRAM Receiver Section –95.0dBm –99.5dBm SW –94.0dBm SW –98.0dBm –94.5dBm –88.0dBm W/SW/N W/SW/N W/SW/N W/SW/N W/SW/N –118.0dBm –121.0dBm –109.0dBm –106.5dBm –120.5dBm –110.0dBm 62mVrms 30mVrms 0.45Vrms 820mVrms 820mVrms 16mVrms SG input level for 12dB SINAD are obtained measured by AF VTVM connecting SG to each point via a 0.01µF capacitor.

  • Page 65: Terminal Function

    TK-780 TERMINAL FUNCTION CN7 (TX-RX Unit) ← → CN502 (Control Unit) CN101 (VCO) ← → TX-RX Unit Pin No. Name Function Pin No. Name Function Wide/Narrow switch. H : Wide Switched transmit input. H : Transmit TX/RX switch. H : Receive RF output.

  • Page 66: Specifications

    TK-780 SPECIFICATIONS GENERAL Frequency Range ........ 146 to 174MHz Number of Channels ......Maximum 250 channels Channel Spacing ......... 12.5/20/25kHz Input Voltage ........13.2V DC negative ground Current Drain ........0.4A on standby 1.0A on receive 8A on transmit Temperature Range ......–30°C to +60°C Frequency Stability ......
  • Page 67 Mechelsesteenweg 418 B-1930 Zaventem, Belgium KENWOOD ELECTRONICS FRANCE S.A. 13, Boulevard Ney, 75018 Paris, France KENWOOD ELECTRONICS U.K. LIMITED KENWOOD House, Dwight Road, Watford, Herts., WD1 8EB United Kingdom KENWOOD ELECTRONICS EUROPE B.V. Amsterdamseweg 37, 1422 AC Uithoorn, The Netherlands KENWOOD ELECTRONICS ITALIA S.p.A.

Table of Contents