Kenwood TS-830S Deafened Receive Repair!

I'm currently in the process of improving my CW skills so I find this very interesting.

I noticed in the alignment procedure that there are -M specific adjustments. What is the difference between the -S and the -M?

 

I have an Inrad 400 Hz CW filter in my TS-830S and it is like night and day where CW reception is concerned. Also, zero-beating correctly the other station is much easier than with the normal SSB filter.

Although I do have a pretty good cerebral filter, using the 400 Hz filter does make CW reception a lot easier. Unfortunately, the Inrad filters are not cheap! However, for the serious operator, the expense is well worth the cost.

Glen, K9STH

 

The -M deleted "CW Narrow" from the Mode switch and added an AM position. The 455KHz CW filter slot was filled by a 6KHz B/W, 455.7KHz ceramic filter. A YK-88A and a YK-88S1 filter were fitted in the 8.83MHz filter slots, and a small auxiliary PCB which demodulated an AM signal was added to the rear of the chassis, using existing connectors and wiring.

The Mode switch wiring is slightly different. All this is shown in W0NTA's copy of the TS-830S Service Manual. If one wanted to convert an -S to an -M, the only hard-to-find parts are that 455KHz AM filter and one of the inductors on the AM Converter Unit...and as I recall, PacParts still lists those as available to order. Failing that, one could cannibalize other Kenwoods of the era for the required components.

I found front panels, the AM Converter Unit (with mounting hardware) and an 'M' model IF Unit on eBay. The VFO Assembly still says "TS-830S" and I'll leave it as-is until an "M" part pops up for sale.

Kenwood used AME (exalted carrier AM) on the transmit side of things, and I'm going to mod mine for RF pre-driver modulation when operated on AM. This is similar to a published mod for the TS-940S.

 

As posted above, the M unit supports AM transmission and reception, the S unit does not.

I second a pair of matched CW filters. Realistically the Kenwood CW filters aren't bad, but if it's in the budget a pair of 400 Hz CW filters from Inrad really let the rig shine on CW.

 

Excellent Postings and Thread! Years ago I rewound my L-41 to make my radio work but broke the can so it was messy. I too just installed a new L-41 that I ordered from Walter, KD7DNY. While the RF board was out of the radio I gave it a bath in soapy water as per K4EAA then surface washed the board with alcohol and a paint brush. Then I removed the band switch wafers one by one so as not to get 'em mixed up, soldered some loose rivets in the wafers and now the radio works great except for an intermittent reduction in drive that causes the ALC to drop and the ALC reading to "Jiggle" around some with some slight fluctuations in output power, not enough to lose 100% power though. That problem has been there for years and will go months without happening. I think I've found the issue to be the cable connections on connector 6 of the IF board which carries signal to the RF board possibly the crimp connection inside the connector. Anyone know if these cable connectors can be found anywhere?

 

I had a look at one of my '830s and see that two Miniax runs are terminated in IF Unit J6. Are one of these the source of your rig's troubles?

The connector itself is a Taiko Denki TP25 series. I have been trying to find the crimp sockets for those things forever, give or take a month of Sundays. What I have been doing (and what I'll counsel you to do as well) in the case of single wire leads is to extract a good crimp socket from a junked wiring harness connector with a small jewelers's screwdriver, cut about 1-2" of the lead near the connector and strip/tin the end. Extract the faulty one from your rig's harness connector, cut/strip/tin then solder the replacement lead inline. Use heat shrink to cover the joint and try to use the same color wire (from the scrap harness) as the faulty connector was crimped onto.

As far as the coaxial run...identify exactly which one is bad (including any special color banding or other marking) then get in touch with either Walter or Bob, KE5FTF. Describe to them which run you need and see if they'll sell the Miniax in question or an entire scrapped wiring harness. Be sure to emphasize you want a harness with none of the Miniax runs cut up, as some who are in a hurry to part out a rig will often do.

A scrapped '530 harness will also yield the Miniax run you need.

 

I have soldered many rivets in the day.

You have to be very careful.

Flux, Fast on fast off. Then wash, Should not need to repeat.

 

Is there any downside to just cleaning and soldering all of the riveted connections while the RF board is taken apart? So that the process would "never" have to be repeated.

 

Not really.

Just use flux, It can be your friend. Solder with flux is not the same as what you can add to make a good connection.

Cleaning before soldering and added flux makes a nice connection with minimal heat.

Just wash it off, And do not believe when you hear about No Clean Flux.

That is false news, With high hopes. Made up by tree hungers that want to protect tree sap.

 

And it just plain LOOKS nasty... yeah, don't use it. Find some real solder.