Ampeg Reverb Rocket B12R

[bsco]

Hi all... Have an Ampeg Reverb Rocket B12R here and it had a spill....Replaced damaged socket and noticed that the base of the tube. a 6L6 has an arc between the plate and heater pins...2 and 3....Does anybody know what the bias setting for this amp is and where this setting is actually measured...Tried looking for a schematic but couldn't find anything so I figured I'd ask here to see if anybody had some info....
Cheers,
Bernie

[Enzo]

B12R? MAybe R12R?

Are we talking an old amp here, or the SLM reissue?

Bias seting would not be the cause of an arc across tube or socket.

Tube current, which is adjusted by bias, would be measured by inserting a "bias probe" socket under the tube, or by having a 1 ohm or other sensing resistor between cathode and ground of a tube.

[bsco]

Hi Enzo...yes this is an old amp...similar to an old hot rod deluxe...the reason for the arc across the tube and it's socket is that somebody spilled a drink inside it...I replaced the socket...cleaned up the tube base but there is a small burn mark between pins 2 and 3 of the tube, so I was going to replace the tube..... I wanted to check the bias while I had this thing opened up......I was looking around for a bias measuring point but couldn't find anything...In order to insert a 1 ohm resistor in the cathode circuits of both tubes, I would need to cut a couple of traces, which is why I posted hoping that there would be a place on the output board to measure bias voltage while the bias pot was adjusted.....or if somebody happened to have a schematic for the unit........(don't have a bias probe)...and this guy wants his amp for the weekend.. Suggestions??????
Cheers,
Bernie
Maybe I should get a couple of extra sockets and modify them with 1 ohm resistors and construct my own bias probe.....I will check into it....should be some diagrams on the net.....

[g1]

These kits are fairly cheap: TubeDepot Bias Scout Kit Buying the parts separately would probably cost near that.
The instruction pdf will probably show you what you need to know.
It does say it won't do 7591 output tubes, not sure what is in that Ampeg.

[doctor]

These kits are fairly cheap: TubeDepot Bias Scout Kit Buying the parts separately would probably cost near that.
The instruction pdf will probably show you what you need to know.
It does say it won't do 7591 output tubes, not sure what is in that Ampeg.

May be this.