Kenwood TK-780 Service Manual

[Page 1] Kenwood TK-780 series

© 2002-2 PRINTED IN JAPAN B51-8523-10 ( N ) 388 VHF FM TRANSCEIVER TK-780 SERVICE MANUAL GENERAL ................................................................. 2 OPERATING FEATURES ......................................... 3 REALIGNMENT.........

[Page 2] Kenwood TK-780 series

2 TK-780 GENERAL INTRODUCTION SCOPE OF THIS MANUAL This manual is intended for use by experienced techni- cians familiar with similar types of commercial grade com- munications equipment. It contains all required service in- formation for the equipme...

[Page 3] Kenwood TK-780 series

3 TK-780 4. INSTALLATION PLANNING – CONTROL STATIONS 4-1. Antenna system Control station. The antenna system selection depends on many factors and is beyond the scope of this manual. Your KENWOOD dealer can help you select an antenna sys- tem that ...

[Page 4] Kenwood TK-780 series

4 TK-780 2-2. Programmable Keys The FPU (KPG-60D) enables programmable keys to se- lect the following functions. ■ Auto Dial To transmit the stored DTMF code automatically. When you select DTMF encode in the “Auto dial mode” menu, Auto dial, R...

[Page 5] Kenwood TK-780 series

5 TK-780 ■ Group Up/Down When this key is pressed each time, the group number to be selected is increased/decreased and repeats if held for one second or longer. ■ Home Channel Press this key once, the channel switches to the preprogrammed home c...

[Page 6] Kenwood TK-780 series

6 TK-780 ■ Receive Entry (5-tone) Press [Receive entry] key to enter the desired Selcall code you want to receive. This function can be activated only when “RX address” is set to the channel and “select- able receive digit” has been entere...

[Page 7] Kenwood TK-780 series

7 TK-780 ■ Status Entry (5-tone) It allows the operator to input the status and transmit it to the base station. Both TX address and “Selectable status digit” must be programmed to perform the operation. Press [Status entry] key to access Stat...

[Page 8] Kenwood TK-780 series

8 TK-780 2-3. Front Panel Displays and Indicators 1 Sub display Displays the system, channel and group numbers. Also displays various functions, such as TA. 2 P (Priority) indicator The P indicator ( ) appears when a selected channel is programmed a...

[Page 9] Kenwood TK-780 series

9 TK-780 ■ Scan channel types 1) Priority channel is the most important channel for the scan, and always detects a signal during scan and when the scan stops temporarily. 2) Non-priority channels detects a signal during scan. For the channels that...

[Page 10] Kenwood TK-780 series

10 TK-780 ■ Com port • Com 0 This function selects the external serila port function at the microphone jack (TXD/RXD). PC programming is ac- cepted, regardless of this setting. • Com 1 This function selects the external COM1 pin serial port fu...

[Page 11] Kenwood TK-780 series

11 TK-780 ■ “TOT” pre-alert The transceiver has “TOT” pre-alert timer. This param- eter selects the time at which the transceiver generates “TOT” pre-alert tone before “TOT” is expired. “TOT” will be expired when the selected t...

[Page 12] Kenwood TK-780 series

12 TK-780 OPERATING FEATURES ■ Selective Call (SELCALL) This is a voice call to a particular individual or group of stations. • Example of call types; [100][ALL ] : <Group Call> All the units whose fleet number is “100” are called. [100...

[Page 13] Kenwood TK-780 series

13 TK-780 OPERATING FEATURES ■ GPS Report A NMEA-0183 GPS unit must be installed. • GPS Report Mode GPS data can be sent automatically or upon request. Manually sending GPS data works regardless of this setting. Auto : GPS data is sent both auto...

[Page 14] Kenwood TK-780 series

14 TK-780 ■ Monitor Function You can select either QT/DQT or 5-tone decoding to be canceled when [Monitor] or [Monitor momentary] key is pressed. When monitor function is activated, “MON” icon appears. When the transceiver is set up in “QT/D...

[Page 15] Kenwood TK-780 series

15 TK-780 ■ Decode Code When “Special setting” is disabled, you can select the decode code setting from #1 to #8. The transceiver tries to decode the selected decode code setting (maximum 8 dif- ferent settings) at the same time. When the cod...

[Page 16] Kenwood TK-780 series

16 TK-780 1. Modes REALIGNMENT User mode Panel test mode PC mode Firmware program- ming mode Panel tuning mode Data program- ming mode PC test mode PC tuning mode Self programming mode Clone mode Mode Function User mode For normal use. Panel test mod...

[Page 17] Kenwood TK-780 series

17 TK-780 REALIGNMENT 5-5. Programming With IBM PC If data is transferred to the transceiver from an IBM PC with the KPG-60D, the destination data (basic radio informa- tion) for each set can be modified. Normally, it is not neces- sary to modify th...

[Page 18] Kenwood TK-780 series

18 TK-780 REALIGNMENT 7-2. Channel Setting Mode Each channel can be setup in its action mode by using the panel keys. • Pressing [■] while “SELF PROG” is displayed will change to channel setting mode. • Press [D] to select a setup item, the...

[Page 19] Kenwood TK-780 series

19 TK-780 1. Accessory Connection Cable (KCT-19 : Option) The KCT-19 is an accessory connection cable for con- necting external equipment. The connector has 15 pins and the necessary signal lines are selected for use. 1-1. Installing the KCT-19 in t...

[Page 20] Kenwood TK-780 series

20 TK-780 R6 R5 R84 R51 R13 R12 R167 R24 R94 R168 INSTALLATION 1-3. Data Equipment Connection The jumpers must be set to either one for each function. Otherwise, the radio will not work properly. ME/AM R12 (0Ω) R167 (0Ω) Function / Default Yes No...

[Page 21] Kenwood TK-780 series

21 TK-780 INSTALLATION 3. Optional Board Terminal Terminal is for mounting the option board are provided at the TX-RX unit (A/2) and TX-RX unit (B/2); Control section. The table below shows the correspondence between the board and terminals. Disconn...

[Page 22] Kenwood TK-780 series

22 TK-780 INSTALLATION 4. Ignition Sense Cable (KCT-18 : Option) The KCT-18 is an optional cable for enabling the ignition function. The ignition function lets you turn the power to the transceiver on and off with the car ignition key. If you use the...

[Page 23] Kenwood TK-780 series

23 TK-780 INSTALLATION 6-2. Modifying the Transceiver • Horn alert The signal from pin 4 of IC7 on the TX-RX unit (A/2) turns Q4 and Q6 on and off and drives KAP-1 HA relay to drive the horn with a maximum of 2A. The default output is HR1. The rel...

[Page 24] Kenwood TK-780 series

24 TK-780 INSTALLATION 2. Fold the flat cable ( 1 ) in the opposite direction ( 2 ). 3. Rotate the control section ( 3 ) 180 degrees ( 4 ). 4. Insert the flat cable into the control section connector, CN502 ( 5 ). 5. Mount the control section on the ...

[Page 25] Kenwood TK-780 series

25 TK-780 8. External Speaker 8-1. KES-3 : Option The KES-3 is an external speaker for the 3.5-mm-diam- eter speaker jack. • Connection procedure 1. Connect the KES-3 to the 3.5-mm-diameter speaker jack on the rear of the transceiver. KES-3 Fig. 12...

[Page 26] Kenwood TK-780 series

26 TK-780 Frequency Configuration The TX-RX unit (A/2) incorporates a VCO, based on a frac- tional N type PLL synthesizer system, that allows a channel step of 5, 6, and 25kHz to be selected. The incoming signal from the antenna is mixed with a firs...

[Page 27] Kenwood TK-780 series

27 TK-780 ■ AF Signal System The detection signal (DEO) from the TX-RX unit (A/2) goes to the audio processor (IC504) of the TX-RX unit (B/2). The signal passes through a filter in the audio processor to adjust the gain, and is output to IC502. IC...

[Page 28] Kenwood TK-780 series

28 TK-780 ■ Unlock Circuit During reception, the TR signal goes high, the KEY signal goes low, and Q10 turns on. Q11 turns on and a voltage is applied to the collector (8R). During transmission, the TR signal goes low, the KEY signal goes high an...

[Page 29] Kenwood TK-780 series

29 TK-780 ■ Display Circuit The CPU (IC511) controls the shift register (IC508) and display LEDs. When the LG line goes high when the trans- ceiver is busy, Q508 turns on and the green LED on D511 lights. In transmit mode, the LR line goes high, ...

[Page 30] Kenwood TK-780 series

30 TK-780 ■ Horn Control The horn switch, consisting of Q4, Q5, and Q6, controls the horn relay. It is supplied by the dealer to provide the external horn alert function. Q5 disables horn alert, turning on when its base is high, to inhibit the fun...

[Page 31] Kenwood TK-780 series

31 TK-780 SEMICONDUCTOR DATA ■ Terminal function Pin No. Name I/O Function 1 LSDOUT O Low speed data output. 2 HSDOUT O High speed data output. 3 HSDIN I High speed data input. 4 DTMSTD I DTMF decode IC data detect input. 5 SELF I Self programming ...

[Page 32] Kenwood TK-780 series

32 TK-780 SEMOCONDUCTOR DATA / DESCRIPTION OF COMPONENTS DESCRIPTION OF COMPONENTS TX-RX Unit (A/2) Ref. No. Use / Function Operation / Condition IC1 DC amp FC, TCXO control IC2 DET amp External DEO, internal DEO IC3 Amp/Summing amp DI / DI and MO ad...

[Page 33] Kenwood TK-780 series

33 TK-780 Ref. No. Use / Function Operation / Condition Q24 W/N switch Wide time on Q25 TOF switch Q22 on time on Q26 Inverter Power switch “L” time on Q27 SB switch Q28 on time on Q28 SB SW control Q30 on and Q31 off time on Q29 H/L switch High ...

[Page 34] Kenwood TK-780 series

TK-780 PARTS LIST 34 * New Parts. indicates safety critical components. Parts without Parts No. are not supplied. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Teile ohne Parts No. werden nicht geliefert. L : Scandinavia K : U...

[Page 35] Kenwood TK-780 series

TK-780 PARTS LIST 35 Ref. No. Address Parts No. Description Ref. No. Address Parts No. Description New Desti- parts nation New Desti- parts nation TX-RX UNIT (X57-6142-XX) C74 C92-0719-05 ELECTRO 47UF 25WV C75 C92-0044-05 CHIP-ELE 47UF 10WV C76 CK73G...

[Page 36] Kenwood TK-780 series

TK-780 PARTS LIST 36 Ref. No. Address Parts No. Description Ref. No. Address Parts No. Description New Desti- parts nation New Desti- parts nation TX-RX UNIT (X57-6142-XX) C256 C93-0557-05 CHIP C 7.0PF D E3 C257 C93-0666-05 CERAMIC 24PF C258 C93-0668...

[Page 37] Kenwood TK-780 series

TK-780 PARTS LIST 37 Ref. No. Address Parts No. Description Ref. No. Address Parts No. Description New Desti- parts nation New Desti- parts nation TX-RX UNIT (X57-6142-XX) C593 CK73GB1H103K CHIP C 0.010UF K C594,595 CC73GCH1H270J CHIP C 27PF J C596 C...

[Page 38] Kenwood TK-780 series

TK-780 PARTS LIST 38 Ref. No. Address Parts No. Description Ref. No. Address Parts No. Description New Desti- parts nation New Desti- parts nation TX-RX UNIT (X57-6142-XX) R34 R92-1252-05 CHIP R 0 OHM J 1/16W R35 RK73GB1J223J CHIP R 22K J 1/16W R36 R...

[Page 39] Kenwood TK-780 series

TK-780 PARTS LIST 39 Ref. No. Address Parts No. Description Ref. No. Address Parts No. Description New Desti- parts nation New Desti- parts nation TX-RX UNIT (X57-6142-XX) R224 R92-1252-05 CHIP R 0 OHM J 1/16W R225 RK73GB1J820J CHIP R 82 J 1/16W R226...

[Page 40] Kenwood TK-780 series

TK-780 PARTS LIST 40 Ref. No. Address Parts No. Description Ref. No. Address Parts No. Description New Desti- parts nation New Desti- parts nation TX-RX UNIT (X57-6142-XX) R584 R92-1252-05 CHIP R 0 OHM J 1/16W R585,586 RK73GB1J473J CHIP R 47K J 1/16W...

[Page 41] Kenwood TK-780 series

TK-780 PARTS LIST 41 Ref. No. Address Parts No. Description Ref. No. Address Parts No. Description New Desti- parts nation New Desti- parts nation TX-RX UNIT (X57-6142-XX) PLL/VCO (X58-4712-70) PLL/VCO (X58-4712-70) IC9 TA78L05F MOS IC IC10 LA4422 BI...

[Page 42] Kenwood TK-780 series

TK-780 PARTS LIST 42 Ref. No. Address Parts No. Description Ref. No. Address Parts No. Description New Desti- parts nation New Desti- parts nation R114 RK73GB1J271J CHIP R 270 J 1/16W R115,116 RK73GB1J470J CHIP R 47 J 1/16W R117 RK73GB1J473J CHIP R 4...

[Page 43] Kenwood TK-780 series

43 TK-780 EXPLODED VIEW Parts with the exploded numbers larger than 700 are not supplied. 1 2 A B C 25 1 28 26 46 14 30 23x2 12 11 8 29 17 18 IC400 26 27x2 J501 20 6 42 13 28 15 2 28 3 16x2 31 J1 TX-RX unit (A/2) Sub unit TX-RX unit (B/2) Cx2 704 70...

[Page 44] Kenwood TK-780 series

44 TK-780 PACKING Parts with the exploded numbers larger than 700 are not supplied. D E 1 2 3 37 Protection bag (H25-0720-04) 36 Protection bag (H25-0103-04) 5 Cap (B09-0235-05) 10 DC cord (E30-3438-05) 21 Fuse (F52-0...

[Page 45] Kenwood TK-780 series

45 TK-780 ADJUSTMENT Test Mode ■ Test Mode Operating Features This transceiver has a test mode. To enter test mode, press [B] key and turn power on. Hold [B] key until test channel No. and test signalling No. appears on LCD. Test mode can be inh...

[Page 46] Kenwood TK-780 series

46 TK-780 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). Use [D] button to select the adjustment item through tun- ing modes. U...

[Page 47] Kenwood TK-780 series

47 TK-780 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 –7d...

[Page 48] Kenwood TK-780 series

48 TK-780 ADJUSTMENT Adjustment Location ■ Switch MODULAR MIC JACK CALL CALL DC SOURCE BUSY/ TX LED VOLUME UP VOLUME DOWN CHANNEL UP CHANNWL DOWN SUB DISPLAY MONITOR PRIORITY SERVICE AUXILIAY HANDSET SCAN MAIL PROGRAMMABLE FUNCTION KEYS ALPHANUM...

[Page 49] Kenwood TK-780 series

49 ADJUSTMENT Measurement Test- equipment Unit Terminal Adjustment Unit Parts Method Specifications/RemarksConditionItem TK-780 Receiver Section 1. Discriminator 1) Set test mode SSG Rear ANT TX-RX L6 AF output voltage CH : CH1 - Sig1 panel (A/2) max...

[Page 50] Kenwood TK-780 series

ADJUSTMENT Measurement Test- equipment Unit Terminal Adjustment Unit Parts Method Specifications/RemarksConditionItem 50 TK-780 5. Squelch 1) Set test mode SSG Rear ANT Squelch must be (Tight) Select “nL SQLT” in tuning mode. panel closed once. S...

[Page 51] Kenwood TK-780 series

51 ADJUSTMENT Measurement Test- equipment Unit Terminal Adjustment Unit Parts Method Specifications/RemarksConditionItem TK-780 Transmitter Section 1. Frequency 1) Set test mode Power meter Rear ANT Check 160.100MHz±100Hz Select “FREQ” in tuning...

[Page 52] Kenwood TK-780 series

ADJUSTMENT Measurement Test- equipment Unit Terminal Adjustment Unit Parts Method Specifications/RemarksConditionItem 52 TK-780 7. Maximum 1) Set test mode Power meter Rear ANT 4.1kHz (Wide) +0Hz/–50Hz deviation Connect AG to the MIC Deviation pane...

[Page 53] Kenwood TK-780 series

53 ADJUSTMENT Measurement Test- equipment Unit Terminal Adjustment Unit Parts Method Specifications/RemarksConditionItem TK-780 11. DTMF 1) Set test mode Power meter Rear ANT 3.0kHz (Wide) ±0.2kHz (Wide/Semi-wide) deviation Select “n DTMF” in tu...

[Page 54] Kenwood TK-780 series

AC E BD 1 3 5 7 2 4 6 TK-780 PC BOARD VIEWS Component side Foil side CN101 ST HT E 9CL 8CL MD CV J72-0732-02 C107 C121 C103 C102 C117 C119 R110 C108 R102 C126 C115 L101 C105 R117 R106 R104 C113 R115 R113 L102 R114 R111 C130 D101 D102 R118 D104 C131 ...

[Page 55] Kenwood TK-780 series

A B C D E F G H I J K L M N O P Q R S 1 2 3 4 5 6 7 8 9 10 11 12 13 14 1 3 1 3 E LOK E DEO RD2 5C C4 C3 OP SQ RD1 TD2 TD1 FW C2 SQ2 C1 +B E BPO BP TP3 TP1 TP2 TV IC11 IC5 1 12 13 24 D32 D37 IC300 1 1011 20 D7 C101 R317 R315 R57 R413 Q403 Q402 C94 C91...

[Page 56] Kenwood TK-780 series

S R Q PONML KJ IHG FE DCB A 1 2 3 4 5 6 7 8 9 10 11 12 13 14 C150 R71 R72 R73 R65 C95 R63 R70 R25 R150 C115 D17 D4 D1 R10 R11 D5 D3 D2 1 33 Q27 B E C D28 C24 C51 C119 + O G I R67 C127 R21 C22 C18 C64 C57 C56 C60 C58 Q18 R133 C84 C103 C114 + C113 R132...

[Page 57] Kenwood TK-780 series

A B C D E F G H I J K L M N O P Q R S 1 2 3 4 5 6 7 8 9 10 11 12 13 14 1 3 1 3 E LOK E DEO RD2 5C C4 C3 OP SQ RD1 TD2 TD1 FW C2 SQ2 C1 +B E BPO BP TP3 TP1 TP2 TV IC11 IC5 1 12 13 24 D32 D37 IC300 1 10 11 20 D7 C101 R317 R315 R57 R413 Q403 Q402 C94 C9...

[Page 58] Kenwood TK-780 series

S RQP O NMLK J IHGF E D CB A 1 2 3 4 5 6 7 8 9 10 11 12 13 14 C503 R513 IC512 8 5 1 4 IC511 R520 R506 IC504 1 11 1222 + + 23 33 34 44 X501 R666 1 100 25 26 50 51 75 76 R665 R664 R670 R663 R675 R662 R661 R660 R659 R658 D504 R657 D505 R505 R656 R655 R6...

[Page 59] Kenwood TK-780 series

A B C D E F G H I J K L M N O P Q R S 1 2 3 4 5 6 7 8 9 10 11 12 13 14 C503 R513 IC512 8 5 1 4 IC511 R520 R506 IC504 1 11 1222 + + 23 33 34 44 X501 R666 1 100 25 26 50 51 75 76 R665 R664 R670 R663 R675 R662 R661 R660 R659 R658 D504 R657 D505 R505 R65...

[Page 60] Kenwood TK-780 series

TRPNLJHFDB SQ OMKIGECA 1 3 5 7 2 4 6 SCHEMATIC DIAGRAM TK-780 Note : Components marked with a dot (·) are parts of layer 1. 68 ...

[Page 61] Kenwood TK-780 series

69 ACEGI KMOQS BD F H J L N P R T 1 3 5 7 2 4 6 TK-780 SCHEMATIC DIAGRAM Note : Components marked with a dot (·) are parts of layer 1. ...

[Page 62] Kenwood TK-780 series

TK-780 TK-780 TK-780 BLOCK DIAGRAM 75 ...

[Page 63] Kenwood TK-780 series

7776 LEVEL DIAGRAM –118.0dBm –121.0dBm –109.0dBm –106.5dBm –120.5dBm –110.0dBm W/SW/N 16mVrms W/SW/N 820mVrms W/SW/N 820mVrms W/SW/N 30mVrms W/SW/N 62mVrms 0.45Vrms W –95.0dBm SW –94.0dBm N –88.0dBm W –99.5dBm SW –98.0...

[Page 64] Kenwood TK-780 series

78 TK-780 TERMINAL FUNCTION CN7 (TX-RX Unit A/2) ←→ CN502 (TX-RX Unit B/2) Pin No. Name Function 1 W/N Wide/Narrow. H : Wide 2 T/R TX/RX switch. H : Receive 3 MO Modulation signal. 4 TO Low speed data signal. 5 BEEP Beep. 68R NC 7 PSW Power swi...

[Page 65] Kenwood TK-780 series

79 TK-780 SPECIFICATIONS GENERAL Frequency Range ................................ 146 to 174MHz Number of Channels ........................... Maximum 250 channels Channel Spacing ................................. Narrow : 12.5kHz Wide 4k : 20kHz ...

[Page 66] Kenwood TK-780 series

KENWOOD CORPORATION 14-6, Dogenzaka 1-chome, Shibuya-ku, Tokyo 150-8501, Japan KENWOOD SERVICE CORPORATION P.O. BOX 22745, 2201 East Dominguez Street, Long Beach, CA 90801-5745, U.S.A. KENWOOD ELECTRONICS CANADA INC. 6070 Kestrel Road, Mississauga, O...