Kenwood TS 930S Service Manual

The Kenwood TS 930S is a high-performance amateur radio transceiver featuring general coverage receiver, 160-10 meter transmit coverage, built-in antenna tuner, dual VFOs, digital frequency display, noise blanker, IF shift, and multiple filter options. Below are key sections for technical specifications, block diagrams, alignment procedures, troubleshooting, schematics, and parts list.

1. Technical Specifications 2. Block Diagrams 3. Alignment Procedures 4. Circuit Descriptions 5. Troubleshooting Guide 6. Schematic Diagrams 7. Parts List 8. Mechanical Assembly 9. Test Equipment Requirements 10. Service Notes 11. Warranty Information

Technical Specifications

Key technical parameters and performance characteristics of the Kenwood TS 930S transceiver.

Parameter	Specification
Frequency Coverage	Receive: 100kHz-30MHz, Transmit: 160-10 meters
Modes	SSB, CW, AM, FM
Power Output	200W PEP (SSB), 200W (CW), 60W (AM)
Sensitivity	SSB/CW: 0.25μV for 10dB S/N
Selectivity	2.4kHz, 500Hz, 250Hz (optional filters)
VFO Stability	Less than 100Hz after warm-up
Power Requirements	13.8V DC, 22A max
Dimensions	420(W) x 145(H) x 380(D) mm
Weight	Approx. 15 kg
Antenna Impedance	50 ohms unbalanced

Block Diagrams

System block diagrams showing signal flow and major circuit sections.

RF Section: Front end, preselector, and mixer stages
IF Section: Multiple conversion stages with crystal filters
Audio Section: Receive audio amplification and processing
Transmit Section: Microphone amp, modulator, and PA stages
Control Section: Microprocessor and interface circuits

WARNING! High voltages present in transmitter section. Use extreme caution when servicing.

Alignment Procedures

Step-by-step alignment instructions for proper performance.

Receiver alignment: RF preselector, IF stages, and detector
Transmitter alignment: Carrier insertion, modulation balance, and power output
VFO calibration: Frequency counter required for accuracy
Filter alignment: SSB and CW filter adjustments
Meter calibration: S-meter and power output meter

CAUTION! Use proper test equipment and follow procedures exactly.

Circuit Descriptions

Receiver Front End: RF amplifier, preselector, and first mixer
IF System: 8.83MHz and 455kHz IF stages with selectivity filters
Product Detector: SSB and CW detection circuits
Transmitter Chain: Microphone amp, balanced modulator, and driver stages
Power Amplifier: Final amplifier with protection circuits
Power Supply: 13.8V DC input with regulation
Control Circuits: Microprocessor and interface logic
Display System: Digital frequency counter and LED display

Troubleshooting Guide

Systematic approach to diagnosing and repairing common issues.

Basic Checks: Power supply voltages, fuses, connectors, and cables.

Receiver Problems: No reception, poor sensitivity, distorted audio, no AGC action. Transmitter Problems: No output, low power, distorted modulation, VFO problems. Control Problems: Display issues, button non-response, memory loss.

Schematic Diagrams

Complete schematic diagrams for all circuit boards and modules.

Main Unit: Receiver and transmitter circuits
Power Supply: Voltage regulation and distribution
Control Unit: Microprocessor and display circuits
Filter Units: SSB and CW filter boards
Optional Units: Accessory interface circuits

Tip: Use high-quality prints for best readability of component values.

Parts List

Complete component listing with part numbers and specifications.

Semiconductors: Transistors, ICs, diodes with replacement types
Passive Components: Resistors, capacitors, inductors values
Mechanical Parts: Knobs, shafts, brackets, and hardware
PC Boards: Board numbers and descriptions
Optional Parts: Accessory components and kits
Test Points: Voltage and signal test points
Adjustment Points: Trimmer pots and variable components
Connectors: All external and internal connectors

WARNING! Use only specified replacement parts for safety and performance.

Mechanical Assembly

Disassembly and reassembly instructions with exploded views.

Test Equipment Requirements

Essential test equipment for proper servicing and alignment.

Oscilloscope, RF signal generator, frequency counter, power meter, dummy load, multimeter, audio generator, distortion analyzer.

CAUTION! Use properly calibrated test equipment for accurate measurements.

Service Notes

Factory service bulletins and common modification notes.

Problem	Solution	Reference
Display flickering	Check +8V supply, regulator IC	Service Bulletin #12
Receiver deaf	Replace RF FETs, check bias	Tech Note #45
TX power low	Adjust carrier balance, check PA bias	Modification #23
VFO drift	Replace reference oscillator	Service Bulletin #18
Memory loss	Check backup battery, diode	Tech Note #51

Updates: Check for latest service bulletins before repair.

Service: Authorized service centers only for warranty work.

Warranty Information

Kenwood warranty terms and service center information. One year limited warranty on parts and labor. Warranty void if serviced by unauthorized personnel. For service, contact authorized Kenwood service centers or visit www.kenwood.com.