G/K 800RB bass head

[bsco]

Hello everybody..I have this for repair and there is one resistor on the power amp board that is burnt up.....it is at location R12.....but I don't have any schematics...only a board layout with no values...just component designations.....anybody here have a power amp schematic for this??
Cheers,

[nevetslab]

I just tried to upload the 800RB service manual, upload isn't working. Meanwhile, R12 is a 3.3k resistor

[Enzo]

Of just call GK and ask them for it.

[g1]

Here's a link to that service manual. R12 is in the 'high' amp and in series with the bias trimmer. For it to burn there must also be other associated parts bad.
https://music-electronics-forum.com/...9&d=1509150768

[bsco]

Of just call GK and ask them for it.

Actually Up here in Canada Yorkville Sound is the agent.....I did not know that before......
Cheers

[bsco]

Here's a link to that service manual. R12 is in the 'high' amp and in series with the bias trimmer. For it to burn there must also be other associated parts bad.
https://music-electronics-forum.com/...9&d=1509150768

Yes there was.....two output transistors, two drivers, one MPAS56 (if memory serves me correct) a 470ohm resistor, a 22 ohm resistor.....and I am not sure about the bias pot.....I have 3.3k resistors here.....but not the bias pot......Maybe I should change that while I am at it......
Cheers

[bsco]

Time for an update.....I changed the bias pot after.....it checked good but I decided to replace it anyway....just in case.......and all the damaged parts...works great now......
Cheers