Kenwood TS-430S Rebuild.



07/13/2011 Most of my spare time for the next few months will be spend refurbishing a Kenwood TS-430S HF Radio.  At this point the unit doesn’t have any RX or TX so it should be a challenge to get everything back into working order.

07/13/2011 Considering the radio’s age I started with basically taking it apart to see if any visible damage could be seen.  My main goal is to ensure the PA is good and perform some modification to ensure it stays that way.


While I had the PA removed, I checked all the LFP relays cleaning and testing each one.  The best way I’ve found to do this is to use contact cleaner and a pieces from a paper bag. Looking at the PA it appears to be in good shape.  The first order of business was to remove all old solder with suction and wick.  I removed the rivets and replaced with Z wires to ensure a long lasting connections to the PA transistors.  One thing to make sure is to make sure the mica insulators are retained during removal.  I did a complete cleaning of the board and sink.  I replaced the aging thermo compound.  A big problem I found was the fan was not connected. After replacing the wire and testing the fan worked.  I know that I want to modify the turn on temp but I’ll do that later.  I tested the transistor connections to make sure no shorts and that everything was ok.  Next order of business was to ensure I had good connections on all the board connectors.  Deoxit was used and I discovered a connector that was not connected to the correct place on the IF board.  After getting it all back together I turned the unit on with all the settings in Alignment position.  Care was taken to make sure the CAR was on lowest setting.  I can now receive and on most bands I now see 95-100 watts of power to a dummy load.  RX doesn’t seem to be very sensitive as I can’t tune in anything. TX seems to work on some bands to the full power.  On other bands the radio seems to have a problem.  As increase of the CAR while TX it pulls the voltage down and the radio resets clicking the relays along with it.

I tore deep into the radio and started alignment.  The boards had some oxidation on them.  I’ve decided while I have it apart to go ahead and replace all oxidized “lytics” just to ensure once back together it’ll last another 15-30 years.   I normally don’t like digging deep into a non-working device always afraid of making it way much harder to troubleshoot existing problems. I’ve noted some questionable solder joints on all boards and did a tedious cleaning of the traces.  The speaker connector from the IF board to the lid was badly damaged.  I managed to replace it with a computer switch header lead which works nicely on all the board connections.  While I’m waiting on caps to begin arriving for the values I don’t have in hand, I’ll be cleaning up the solder joints and testing connections on each board.  During alignment I also noticed that the RIT control isn’t working at all and no signal is present at the test point.  I’ll retest after cleaning it up and soldering.

07/14/2011 Well sourcing caps will take some time unless I can find a ready made list of values and sizing.  If anyone has such a list please let me know.  Otherwise I’ll come up with one as I go and post here to make it easier on others to repair their TS-430S .

08/08/2011 I’ve been continuing work by section in the posts below. I was able to source caps, as needed, from Mouser and Digikey

Below are other articles which continue the work on the 430S

IF Board

Control Board

PLL Board 

Filter Board


08/18/2011  The TS-430S is now completely functional and freshly aligned.  I’ve only made a few contacts on 40 meters but reports were good.

9 Replies to “Kenwood TS-430S Rebuild.”

  1. The counts of parts on ebay didn’t match my spreadsheet of parts and it didn’t take that long just to develop parts list from Mouser. Looking at the board it appears the previous owner may have already tried the cap kit and many of the parts are too big covering the silkscreen and too tight of a fit next to other parts. I just went to mouser and got exact fit parts using the specs from the service guide. Price including shipping came to $22.83 including shipping from Mouser. I don’t plan on recapping the entire unit until I at least get some sort of RX on all bands.

  2. Hi, I have the same rig. It was packed away for years. I hooked it up recently and noticed some bands were dead. I figured it must be the LPF relays. I did the resistor maintenance and it didn’t work. I might need to open up clean up the relays or replace them. The relays are Omron G2. They were no longer availble. Yours look different than mine. What is the writing on the relays? How did you clean the relays and did it work?

  3. The relay’s in my rig are fujitsu. I used a signal generator to check the relays were making connections.. To clean them i took the tops off and used a corner of a dollar bill and some contact cleaner. I did find replacements for the relay’s but they were around $16 per which wasn’t really worth it. Your issue may be something else as well. Can you RX and TX proper on working bands?

  4. I can tx and rx on working bands. I am working on the rig as I am typing. I am trying to remove the PA module. I noticed there were two wires broken off from the x verter connector. One is a shield and the other one is a white wire. No idea where they should connected to. Do you have an email address, so I can email that to you. May be you can tell me where they go. Mean while I will try to clean the relays.

  5. On removing the PA module, I normally remove the jacks from the PA plate also label the connections. If you haven’t already, I would highly recommend replacing the rivets in the PA with Z wire or other mods to make sure the PA transistors don’t loose a connection. I sent you a email with my address if you would like to send photos. Also the service manual should indicate where the broken wires should be connected.

  6. Shane,
    I’m about to embarc on the same project – was given an ailing TS-430 with low power output on all bands & various other ills. Previous owner just gave up & was going to “rotary file” the radio. This radio does have the narrow SSB filter & FM Board.

    Finals & drivers where replaced – not sure if the originals where actually bad or replaced as a “guess”. Radio is in perfect condition cosmetically so if I can get the electrical issues resolved I’ll have a nice shack companion for my Kachina 505DSP.

    You’ve got some excellent info here, and I’ve printed a copy as a guide for my 430 rebuild. Thanks for your work in documenting your project.

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