• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

McAlister PP150

Hi Anyone familiar with the McAlister PP150?

I have the Amp and it performed nicely until one day I lost the right channel. I thought it was one of the sweep tubes that was out but something strange is happening.

I can take the far right tube that is glowing and switch it with the tube in the V7 position or third power tube socket and it will glow. Here's the catch neither right channel of the two output tubes will be glowing together as normal at the same time:confused:
You can put any known working tube in the right to channel output tube sockets and one will be dead and then it will switch over to the other socket and it will be dead.
Is it a resistor issue? I do not have the ability to fix it and do not have the schematics from Peter McCalister. Apparently this is one of several different versions and he is in Canada. I'm in central OH near Columbus and would like to get it back up and running again.
Any help is appreciated. Thanks