lowell 8/4/2018 12:14 PM
Egnater Renegade
I just replaced a blown PT in this amp with a Mercury Magnetics.

Powered it up on my limiter and bulb was very dim so it locked good. Then put EL34 in there...still looked good. Voltages looked low but good for limiter.

Took it off the limiter and got good plate and screen voltages around 400v+. Cant remember exact figure as its the weekend and I'm out of the shop but wanted to get some feedback before Monday if possible. At least I thought the voltages were correct. Played the amp for about 1 minute and BANG a capacitor exploded. Was literally like an M80 lol!!

So C8 in the PA exploded. As far as I know there are 2 reasons a cap will explode... over voltage, and reverse polarity. Neither of which seem likely. Its the only cap that exploded... and the amp still works albeit there's noise now.

I suspect I'll need to investigate further on some voltages in the power supply as this cap feeds the PI. But what are your thoughts on the matter?
 
g1 8/4/2018 2:08 PM
Maybe C8 was going bad and took out the PT, now it just blew?