Nomad 45: round 2

[boogiebomb]

So I was able to revive a mesa nomad 45 which had fried the heater molex plug by soldering the heater wires from the PT onto the power tube pcb points for heaters, bypassing the molex connector. played well on my work bench, put it back together and had a friend test it out. Two of the EL84's are red plating within 5 minutes, and it's the two on the left (when looking at the amp from the back). I'm not 100% sure here, but if it was the bias circuit, wouldn't it be either the two on the inside or the two on the outside? Is it just a coincidence that two have shorted? Picking up the amp tomorrow.

Thanks in advance!

[Jazz P Bass]

The first thing you could try is moving the tubes to the non red plating sockets.
Prove whether it is the tube or the socket.

[g1]

I'm not 100% sure here, but if it was the bias circuit, wouldn't it be either the two on the inside or the two on the outside? Is it just a coincidence that two have shorted?

There is no set rule as to how various manufacturers arrange the output tubes as far as "push" and "pull" sides. Anything goes.
I have seen them paired 2 left, 2 right; or 2 inner, 2 outer; or staggered even sockets, odd sockets.
And I have been caught out mis-diagnosing because I made a similar assumption, that's how I know this.

The swapping test JazzP mentioned is the easiest way to find out if your fault is in the tubes, or in the circuit.