Forming filter caps

Info for maintaining and tweaking your amp to perfection.

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Re: Forming filter caps

Post by syscokid » Fri Jul 28, 2017 2:14 pm

neikeel wrote:That is odd.

Did you remove all of the tubes? (sorry to ask but it has been done)

What you can do is desolder the caps and jumper them + to - with the last one - to ground on the chassis, that way you know they are isolated form the rest of the circuit.
Usually if the caps are no good they bottom out at 20v and then start to climb again.
Success... I think... :?

But first:
I must have misunderstood your suggestion in how to apply it. After setting up the chain of caps, and turning on the amp, the voltage drop and the B+ was identical at 256. I turned it off after a minute.
I thought about the wiring again, and I rewired all positive lugs in series after the dropping resistor. Then grounded individually the three caps to the chassis. 250+ at the start. One minute later, around 20. And after only 20 minutes: 4vdc. The Main F&T cap is about 7 years old. The other 2 new caps are ARS. All 50/50uF (500v).

I've formed new caps before at least 3 to 4 times, and never had a problem. I still don't know why, this time around, I ran into a conflict. Maybe a screwy connection somewhere?
"When I'm on stage and first plug in, and I feel a rush of air in my balls... That's when I know my guitar is sounding good!" -Leslie West

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