Fuse Blows When I Max The OD Pot

[Structo]

You have to call Steve at Apex Jr. to find out what he has on hand.
He doesn't list everything and I think sometime the website lags behind what he has.
When I last ordered wire from him the Teflon shielded cable he sent me was 18ga I think, because he was out of the 20ga.
It works great and I was glad the center was a bit bigger because it was easier to strip.

If you are talking about the wire from the OD trimmer to the 220K resistor, take that sucker out of there. You can always add it back on top of the board.
Make sure the other wire from the trimmer to the cathode ground and 10 Meg resistor is intact.
That is the right hand wire from the trimmer.

Getting back to the redplating issue, are both tubes redplating?
Don't leave the amp on very long at all if they do this.

Check for the negative voltage on Pin 5 to ground. It will be negative -.

Double check plate voltage, Pin 3.

I think the guys are right if those voltages are within spec, you have a parasitic oscillation going on that is pushing your tubes into redplating.

Make sure the wires from the main board are routed cleanly with some separation to the power tubes.

The consensus is to shield all four runs from the Overdrive and Level pot.
I also shield the middle wire on the Master.

Your lead dress is starting to look better.

Sorry I can't help you with the Redplate issue.
You may have to take the amp to a tech or send it to one of the guys here to scope the amp to find the bug.

[flcmcya]

I have some Shielded on the way

Do have - volts on pin 5 and will check the plate v's

I am pulling the jumper and possibly going back to the 500R/ 1k's
as well.

Cranked the preamp and it started fizzing as well....but cut it back before the fuse went.........

Tubes are a nice warm orange but don't seem glowing red at the melting point.

Thanks Tom