[Kenwood] FT930sat

Sat Jul 31 17:22:23 EDT 2004

Hello Mike,
 I recently acquired a "dead" TS-930SAT in a trade. The owner said it was arcing on some tune ups, but he kept using it until it finally died. When I got it, it showed Vc at 28.5V, zero Ic and tiny amounts of power on various bands. I heard it plainly on other rigs while TX-ing into a dummy load so I figured the problem was in the PA board.
 I disconnected the ATU and one day while trying it out again, its simply started TX-ing full power on all bands except intermittantly on 40 meters. OK, the parts are probably good, but something is not quite right. I reinstalled the ATU and it was still working, but sometimes making popping noises while tuning (maybe that was the previous owner's description of arcing). Suddenly, dead again and no luck in getting it up.
 I looked up the possible fixes in mods.dk and followed the instructions for "TS-930S Intermittent TX Power Output". After removing the solder and resoldering just about every component and feed through on the PA board (not a real huge number), I put everything back together and rebiased the output transistors according to the SM (step 5 of TX adjustment). The rig puts out full power now and has so far worked FB. I had to readjust the power setting pot beacuse it was reaching full CW carrier power at only 30% gain, but after that, it worked fine (step 8 and 9 of TX adjustment in SM).
 The 930 is a great rig, and is very rugged. The most often encountered weaknesses are its solder joints and connectors, mostly from being so old. 
Good luck,
Roy
AD6ZU
> Anyone with a 930 that has had transmit problems? I have one I'm trying to 
> revive for a friend. The radio worked well for several years (original owner). 
> Packed away for a relocation. Unpacked 8 weeks later and won't transmit. 
>> The voltages and current readings on the meter in transmit are close to the 
> book specs. The tuner does work. The gain is set full. The mic gain is set 
> mid range and I've tried it in CW and AM with no (less than .1 watts) output. 
> The SWR setting on the meter also produces a small upwards wiggle when 
> transmitting.
>> There appears to be an antenna protection circuit installed looking at the 
> schematic. With all the power and tuner "appearances" looking OK, I suspect a 
> non power related problem. Any suggestions where to start. I do have the Tech 
> manual.
>> Thanks
>> 73, Mike W9MWS