Sorry for the late reply, I've been jamming :shredder Yes I found the Bourns 3296P model has been working well for me. I wanted to let you know, the PCB is very sensitive to heat so use a low power/wattage soldering iron and I recommend carefully snipping off the old trimmers and heating the legs th...

thephantum Great call dude, I got a new reverb tank and all is well. You do hear a small tick when changing over but not at all like it was. I am working on a few circuit upgrades to improve tuning in the bias and will keep you posted. My Marshall MA100H with 1960A cab sounds awesome. Thanks :shredder

Finally, it worked. I removed the tubes from the board, removed adjusting knobs & nuts, removed mount screws and standby connection as well as any connection from knob side. Then I swung the whole board up and started testing components. Could not find anything wrong. Put it back together and gave i...

The tubes are all brand new. Supposed to be a matched set and I purchased all 4 plus the 3 pre amp tubes. Ill check the old el's but i think 2 blew because they stopped glowing. All 4 jj's glow now. I will make sure they are marked EL34's.

I took my Fluke back to work, here are some pics with a Radio Shack meter and slightly different readings. I get pretty close to identical on both outer pins of the test port. FWIW the preamp tubes are jj (x3) ECC 83 S.

Thanks for the response Lizzy, I am reading from each of the outer pins of the factory test port on circuit board to common ground. Just as the image shows in this thread. I was a little surprised to see such a different reading and I am using a Fluke77 meter. My plate voltage is 470VDC. FWIW, I pre...

Thanks for the welcome and I definitely noted the dangerous voltage. I just set up my MA100H but had a much different reading from the bias port with JJ EL34's. I have a question if not imposing too much. Will it make a difference if you have a 16 Ohm speaker load vs. 8 Ohm? I ask because the boxes ...

Wanted to say, sounds like setting up the bias is alot like tuning a FR style floating bridge. While I really like to fiddle around, my son n law doesn't have the same opinion when he tries to Drop D tune it. LOL