Kenwood TS-430S PLL Board.

After getting thru most of the alignment I’ve moved onto the PLL.  The board appeared to be in good shape visually but after doing the first initial checks at TP1 I realized there was a problem.  After carefully removing it I noticed a small gouge on the edge of the board which had broken trace connectivity.  I repaired that with a small bit of foil and solder.  I also realized that the caps had been replaced by the previous owner with larger volt caps which normally doesn’t cause an issue except the fit was too tight and smaller 10V caps are of preference on this board so they fit nicely.  I continued on after removing the caps and ordering parts from Mouser to replace the large 50V rated caps with the 10V.  So more waiting.

After replacing the caps and a complete the alignment the TS-430S now works at least as well as it did new.

Kenwood TS-430S Control Board

I made it a bit deeper into the TS-430S this weekend.  While checking the alignment, it was clear there was an issue with the RIT.  It didn’t seem to work and I wasn’t seeing what I should have been at D5.  After looking around a bit on the board I found that VR3 was working sometimes and sometimes not depending on what mood it was in.  After replacing VR3 I wasn’t getting a proper RIT 9mhz signal but everything is more consistent now.  I noticed the dreaded glue around the 9mhz osc which concerns me and I’m very suspicious of that area.  When I have time next step is to remove all the glue from that area and try and determine if that has something to do with RIT not functioning.

07/24/2011  After deeper inspection of the glue area it became very apparent that X6 (9mhz) was no longer connected to the board. The leads had broken off right at the PCB.  I’ve spent some time trying to source a replacement.  Hopefully I’ll locate one soon.


08/01/2010 The control board now checks out with the 9mhz replacement.  On to the PLL board.






Kenwood TS-430S Filter Unit Board Repair LPF

I’ve been doing some clean up on the filter unit for the Kenwood TS-430S HF radio.  Some bands were not working and the filter unit was suspect.  I had already tried the prescribed 12 V DC current treatment without any changes on the bands that weren’t working.  I noticed several bad joints and manually disassembled each relay and checked its operation. At least two of them were not making good connections and required cleaning with some contact cleaner and a dollar bill.  After this cleaning they seem to be working.  I also noticed several bad solder joints. Here is some photos of the board.


Kenwood TS-430S Clicking on Transmit Problem TX

After doing some initial testing on the Kenwood TS-430S project cleaning up the IF board issues I had been getting 100 watts on some of the bands.  Suddenly last night during a test I noticed the radio would begin clicking and resetting.  After a bit of head scratching and doublechecking power going into the radio I finally traced it down.  The molex connector at the rear wasn’t making a good connection.  I used some needle nose pliers and some deoxit and solved the problem.  A quick fix to a problem is always good.


Kenwood TS-430S IF Board Repair

07/14/2011 – After removing the IF board from the TS-430 I could see some issues right off hand.  The top site of the board was realitivly clean although I noticed some excess thermal compound on the regulators which gave me a hint that this IF board had been repaired at some point.  Getting it out I could see lots of oxidation, burn traces at one of the regulators and at least one connect that had ripped the traces from the board.  Tonight I cleaned up much of the board tested all the diodes on the rear of the board, and repaired the 5V traces.   At this point the radio seems to work but I don’t have very good recieve and it still only transmits on some bands.  On the bands it does transmit on it does full output which is a good sign.  I’ll be working on the IF board for the next few days as its in bad shape on the rear side.

07/18/2011 – Well thus far, I have replaced the traces on the 5V regulator with jumpers as the eyelets were missing and that area of the board wasn’t in very good shape.  I also located a burnt or gouged trace which will need repair.  A missing eyelet was found on Connector 10 and I ended up glueing the connector to the board and replacing the trace with a wire.  After looking at the board from the top I’ve noticed several missing caps.  I expect someone has tried to repair this board and during checking cold solder joints they may of pushed the caps off the board without noticing.

07/19/2011 The gouged trace has been repaired.  Now the IF section seems to be working at least a stage or two away from the audio section.  I ended up with a TX issue which was a bad connection at the molex connector which slowed progress on the IF board issues.





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.