I forgot to unhook my jumper to drain the caps......

[CBD1964]

I for got to unhook my jumper when I drained the caps and turned on the amp.
I replaced the one resistor that I noticed was fried.
The amp will power on but is very low volume and distorted.
Please help. what should I start checking first?

[sluckey]

Which amp? Where did you connect the jumper? Got a schematic?

[CBD1964]

Traynor YBA-1  '71
I hooked the jumper from ground to pin 1 of the preamp tube to drain the caps

[sluckey]

Refer to this schematic... http://www.el34world.com/charts/Schematics/files/traynor/traynor_bassmaster_yba1.pdf

Measure voltage at C20, C21, and C22 and also V1-1. What do you get?

Check R8, R31, and R32. What do they measure?

[CBD1964]

Thanks....I'll Check and see what I get

[LooseChange]

I wouldn't expect much damage with the jumper connected all the way down stream like that. Sluckey will fix ya'.

[Platefire]

Boy I've done that before--a couple of times!!! But I caught it before it did any major damage. Plate

[CBD1964]

C20, 21, 22   450V
R8 370
it looks like I do not have R31 or it is not where it should be...LOL

[sluckey]

R31 is that 4.7K 1W resistor on the lower left end of the board (end near the cap cans). It looks good but you still need to measure it. I want to know what the resistance value for those resistors is, not the voltage on them.

Sounds like you measured voltages for C20, 21, and 22 with tubes pulled out?

[sluckey]

I just realized that the schematic link I posted is not the same as your amp! Your pic shows a bridge rectifier and no choke. That means that all reference designators, ie, R8, R31, and R32, etc., are not valid for this discussion.

Take a look at this pdf. I believe page 7 and/or 8 most closely match your actual amp.
http://www.lynx.bc.ca/~jc/YBA1Schems.pdf

Did you get it fixed yet?