repair notes

This page is no longer actively maintained. More information on repairing the TS-930 may be found on my blog by searching for posts that are tagged ts930. I plan to migrate this page into the main site eventually.

Kenwood TS-930S

Ever since I used one for the first time at W8AV's station in the CQ WW CW, I've been in love with the Kenwood TS-930S. Available in the $450-$700 range, is quite possibly the best buy in used amateur radio transceivers, especially when combined with the PIEXX TS-930SE microprocessor board and cascaded Inrad IF filters. Broken radios can be obtained for even less. Despite having an awesome receiver and outstanding transmit audio on phone, it suffers from poor thermal design in the power supply and power amplifier. Older radios with 2 and 3 million serial numbers also suffer from numerous problems due to poor construction techniques in the Digital, PLL, and PA circuit boards. Most of these are discussed in the Kenwood service bulletins.

A number of helpful fixes and improvements are described in W6NL's article [available at www.kkn.net/~k5tr/ts930fix.html]. Since even the newest '930's are 20 years old, repair is a matter of when, not if. If you have not performed these fixes, I strongly recommend that you do, even if nothing is wrong with your radio. However, Leeson fails to address the most serious failures commonly found in the TS-930S in great detail. I have compiled my repair notes in HTML format for the interested as a sort of addendum to Leeson's already fantastic document. If you were linked directly to this page, please read the Introduction to Repair Notes before trying anything. I also expect some familiarity with the Leeson mods and repairs in addition to the service manual. If enough interest is shown, I'll consider repeating important sections of the service manual here.

  1. 28.5-volt line reads in the ~40-volt range
  2. Dead MRF-485 PA drivers [as a result of #1 above]