Kenwood TK-780 - Service Manual

© 2002-2 PRINTED IN JAPAN
B51-8523-10
(
N
)
388
VHF FM TRANSCEIVER
TK-780
SERVICE MANUAL
GENERAL ................................................................. 2
OPERATING FEATURES ......................................... 3
REALIGNMENT...................................................... 16
INSTALLATION...................................................... 19
CIRCUIT DESCRIPTION ......................................... 26
SEMICONDUCTOR DATA ..................................... 31
DESCRIPTION OF COMPONENTS ....................... 32
PARTS LIST ............................................................ 34
EXPLODED VIEW .................................................. 43
PACKING ................................................................ 44
ADJUSTMENT ....................................................... 45
PC BOARD VIEWS
PLL/VCO (X58-4712-70) ................................... 54
SUB UNIT (X58-4850-10) : E3 .......................... 54
TX-RX UNIT (X57-6142-XX) (A/2) ................... 55
TX-RX UNIT (X57-6142-XX) (B/2).................... 61
SCHEMATIC DIAGRAM ........................................ 65
BLOCK DIAGRAM.................................................. 73
LEVEL DIAGRAM ................................................... 76
TERMINAL FUNCTION ......................................... 78
SPECIFICATIONS................................................... 79
CONTENTS
REVISED E·E3 versions
Cabinet (Upper)
(A01-2165-23)
Panel assy
(A62-0642-03)
Key top
(K29-9105-02)
This Service Manual was revised based on the service
manual as per parts No. B51-8523-00, in order to include
new variants with the following destination codes : E3.

Summary

GENERAL

Personnel Safety

Safety precautions for operators and technicians.

Pre-Installation Considerations

Steps before installing the transceiver, including planning and wiring.

OPERATING FEATURES

Transceiver Controls, Indicators, and Operation Modes

Front panel controls, indicators, and model types.

Programmable Keys and Core Functions

Explanation of programmable keys, channel entry, and emergency call.

Advanced Communication and GPS Features

COM ports, timers, PTT ID, GPS, data transmission, signalling, and tone descriptions.

INSTALLATION

Optional Functions Installation and Configuration

Voice scrambler, PA/HA unit, ignition sense, and speaker installation.

CIRCUIT DESCRIPTION

Frequency Configuration and Receiver System

How frequency is configured and receiver system overview.

Transmitter System and VCO;PLL Circuit

Description of transmitter system and VCO/PLL circuit.

ADJUSTMENT

Test Mode Operations and Controls

How to enter and use test mode, including controls and indicators.

Receiver and Transmitter Adjustments

SPECIFICATIONS

General, Receiver, and Transmitter Specifications

Kenwood TK-780 Specifications

General

Type	Mobile
Frequency Range	136-174 MHz
Channel Capacity	128
Modulation	16K0F3E / 11K0F3E
Channel Spacing	12.5 kHz, 25 kHz
Power Supply	13.8V DC ±15%