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This just looks like a correction for a board layout problem to me. Sometimes there are "issues" with early versions of PCBs. If you get a run of boards done and then discover a layout error you don't usually just scrap the initial boards. The fix is to cut the incorrect traces and create the desire...

Antique Electronic Supply has a dual section axial lead electrolytic that should work. It is 33/33 @ 450v. Part # is c-em33-33-450. Their URL is www.tubesandmore.com.

jd

1) Most likely it is just bad caps in the power supply. 2) Sometimes tubes can fail in a way that leaks the ac filament voltage into the signal path. 3) If all of the diodes on one leg of the transformer short that would feed ac onto the B+ rail causing a buzz. EDIT I hope you won't think I'm an arr...

mertmo

A pipette is like a small plastic eye dropper. It has a bulb like area on one end and a small diameter tube on the other. You squeeze the end, put it into the liquid you are going to use and slurp it up. The fine tip allows you to put the liquid very precisely onto whatever your target is.

jd

mertmo, You probably already know this, but a lot of times you can clean up pots and switches by just exercising them for ten or fifteen cycles. It may make your wrist hurt but it may be worth it. I usually use the products that are made by CAIG Labs. They make a product called Deoxit D5 that is goo...

From my own experience, I would say that the only realistic way to do this is to pull each channel card from the bucket before attempting to clean the pots and switches.There is just no other way to do a decent job. I know there are alot of connectors and such but just make notes or take some digita...

I am trying to locate 12 contact strips for the keyboards of some Korg pianos that have been pounded to death at the local community college. They are officially discontinued at Korg. Parts is Parts no longer has (or can get) any. I guess I bought the last 12 they had for the pianos I already fixed ...

A faint blue or purple glow in an output tube is quite normal. What you need to be worried about is if you see the plate, that big chunk of sheet metal in the tube, glowing even dull red anywhere when the amp is idling, That dull red glow would indicate inadequate bias to keep the tube under control...

You also may want to give Skip Simmons a call. He advertises in TapeOp and may be a shorter drive than Modesto. He's really quite good.

jd

Another issue is that the shield carries phantom ground in a mic cable. If the shield is disconnectd on one end you will not have phantom power to the mic.

jd