Kenwood TK 760G Service Manual

The Kenwood TK 760G is a VHF mobile transceiver designed for professional communications applications. This service manual provides comprehensive technical information, specifications, alignment procedures, circuit descriptions, and troubleshooting guidelines for qualified service technicians. The radio operates in the 136-174 MHz frequency range with 45W output power and features programmable channels, CTCSS/DCS, and robust construction for demanding environments.

1. Technical Specifications 2. Installation Procedures 3. Circuit Description 4. Alignment Procedures 5. Disassembly/Reassembly 6. Test Equipment Requirements 7. Troubleshooting Guide 8. Parts List 9. Schematic Diagrams 10. PCB Layouts 11. Service Notes

Technical Specifications

Complete technical specifications and performance characteristics of the Kenwood TK 760G mobile transceiver.

Parameter	Specification
Frequency Range	136-174 MHz VHF
Output Power	45W (High), 25W (Mid), 5W (Low)
Channel Capacity	64 channels programmable
Modulation	16K0F3E (FM)
Power Supply	13.8V DC ±15% negative ground
Current Consumption	Receive: 0.8A (max audio), Transmit: 12A (45W)
Dimensions	160(W) × 50(H) × 185(D) mm
Weight	Approx. 1.5 kg
Temperature Range	-30°C to +60°C
Frequency Stability	±2.5 ppm (-30°C to +60°C)

Installation Procedures

Proper installation guidelines for mounting and connecting the TK 760G mobile transceiver.

Mounting: Secure unit using mounting bracket in vehicle with adequate ventilation.
Power Connection: Connect red wire to positive terminal, black wire to negative ground.
Antenna Installation: Use appropriate VHF antenna with proper SWR (1.5:1 or better).
Microphone Connection: Plug microphone into front panel connector securely.
External Speaker: Connect optional external speaker if required.

WARNING! Ensure proper fuse protection (15A recommended) and correct polarity to prevent damage.

Circuit Description

Detailed description of major circuit blocks and their functions.

Receiver Section: Double conversion superheterodyne with 45.05 MHz and 455 kHz IF
Transmitter Section: PLL controlled synthesis with 45 MHz IF modulation
PLL Circuit: TC5082P with 12.8 MHz reference oscillator
Power Amplifier: 2SC2879 final transistor with thermal protection
Audio Processing: Compander circuit for improved audio quality
Control Circuit: Microprocessor-based control system

Alignment Procedures

Step-by-step alignment procedures for proper performance adjustment.

Receiver Alignment: Adjust RF amplifier, mixer, and IF stages for optimal sensitivity.
Transmitter Alignment: Set deviation, power output, and modulation characteristics.
PLL Adjustment: Verify reference oscillator and VCO alignment.
Squelch Adjustment: Set squelch thresholds for proper operation.
CTCSS/DCS Alignment: Adjust tone encoder/decoder circuits.

CAUTION! Use specified test equipment and follow procedures exactly. Improper alignment may degrade performance.

Disassembly/Reassembly

Proper procedures for disassembling and reassembling the transceiver.

Remove top and bottom covers by removing specified screws.
Detach front panel assembly carefully from main unit.
Remove main circuit board for component-level service.
Exercise caution with ribbon cables and connectors.
Reassemble in reverse order, ensuring all connections are secure.

Note: Document screw locations and cable orientations during disassembly.

Test Equipment Requirements

Recommended test equipment for proper service and alignment.

Equipment	Specifications
RF Signal Generator	136-174 MHz range, FM modulation
Frequency Counter	9-digit minimum, high impedance probe
Power Meter	50W capacity, 50 ohm impedance
Oscilloscope	20 MHz bandwidth minimum
DC Power Supply	0-15V, 15A capacity with current limiting
Audio Generator	20Hz-20kHz range
Digital Multimeter	High impedance input

Troubleshooting Guide

Systematic troubleshooting procedures for common problems.

Symptom	Possible Cause	Corrective Action
No power	Blown fuse, power cable fault	Check fuse F1 (15A), verify power connections
No transmit	PTT circuit, final PA	Check microphone PTT, test PA stage
No receive	RF stages, squelch circuit	Verify RF amplifier, check squelch settings
Poor sensitivity	Front end alignment, RF amp	Realign receiver front end, check RF transistors
Low power output	PA bias, driver stages	Adjust PA bias, check driver transistors
Frequency error	PLL circuit, reference osc	Check VCO alignment, verify reference oscillator

Parts List

Complete listing of components with part numbers and descriptions.

Main Board: X67-1530-XX (varies by version)
Final Transistor: 2SC2879 (replace as matched pair if required)
PLL IC: TC5082P
Microprocessor: HD404364F
Power Supply Fuse: 15A automotive type
Connectors: Various Molex and Hirose types

Note: Use genuine Kenwood parts for optimal performance and reliability.

Schematic Diagrams

Complete schematic diagrams for all circuit sections.

Main Receiver/Transmitter Circuit
Power Supply and Audio Circuits
PLL Frequency Synthesizer
Control and Display Circuits
Microphone and Accessory Interfaces

Reference: Diagrams show component values, test points, and voltage specifications.

PCB Layouts

Printed circuit board layouts for component placement and routing.

Main Board Component Side
Main Board Solder Side
Front Panel Board
Power Supply Section
RF Module Assembly

Note: Layouts include component designators matching schematic diagrams.

Service Notes

Important service notes and technical bulletins.

Firmware versions and update procedures
Common modifications and upgrades
Known issues and solutions
Component substitution guidelines
Calibration record forms

Service Support: Contact Kenwood authorized service centers for technical assistance and firmware updates.