Realistic trc-431 just stopped TX!??

[Crankcase8934]

A friend of mine gifted me his 1977 TRC-431 navaho and ive gone in and re-capped everything and then gave it a nice alignment using my scope and trusty bird meter.
Its worked excellent for the past month and while talking last night i noticed the RX was fading out then all of a sudden my "on air" and "modulation" lights stopped lighting up and the swr meter just quit. Any thoughts??

 

[Dmans]

Power supply issue?

73
David

 

[Crankcase8934]

Power supply issue?

73
David

I think that is probably where i should start looking... after dinner im going to open her up on the bench.
Besides changing out the caps this thing is stock. I have digital copy of the owners manual with the schematics in the back but thats about it. Everything on cb tricks and everywhere else only tells me about the extra channels mod...