The Electronics Universe

Over The Air => Ham Radio Circuits and Repair => Topic started by: Electrofrying on June 21, 2018, 02:53:33 PM

Title: Kenwood TS-140S Power Down
Post by: Electrofrying on June 21, 2018, 02:53:33 PM

Does anybody have any tips to diagnose a apparently dead Kenwood TS-140S?
This is a newly acquired radio that checked out when i bought it. Send and receive was working, I made contact on the noontime net on the 40M band at the time I picked it up.
I took it home and  I was attempting to make phone contact on the 10M band to a local known contact who i was also on the telephone with.
I was transmitting at 10W with reflected power reading between 0 and 1:1 on my MFJ949D tuner's meter
He said he could hear me key but no voice modulation.
I saw that my MIC GAIN was at MIN so I turned it up to 50% and as soon as I pressed the mic key the unit powered down and is apparently dead now, will not power up at all.
There were no bad smells or sounds.
I tried the reset sequence with no success.

I have experience with tube audio circuits but not much RF anything.
Does anybody have any suggestions where to start with this?
I have some test gear, meters. power supplies, scope, signal generator, etc and I have the service manual but could use some guidance.