Power Section caps (1972 SL restoration)

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RedRox
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Power Section caps (1972 SL restoration)

Post by RedRox » Wed Feb 03, 2021 2:35 pm

Hey guys -

I've got a 1972 Super Lead that I'm restoring. Along it's life, someone clipped out the two large .2uF caps by the diodes on the board. Perhaps when the diodes were also replaced, after one burned out (there's a heat mark on the board underneath one).

Looking at photos of original vintage amps and schematics, I see these caps are not consistently present. I know mine had them, as I can see where the leads were clipped cleanly right at the turrets, with the original solder still undisturbed.

What function do these caps do and do I want to put them back? The amp works without them but it has other preamp issues I'm still restoring so I can't speak to it's sound quality, yet. Are these just some additional ripple filtering to smooth out the AC power? Generally desirable in these amps?

I'm having trouble finding modern .2uF caps rated higher than 630v, and the originals I see are all marked for 1kv.

The caps would be located between the four wide spaced turrets on the far right:
https://www.re-wind.net/risa/_data/i/up ... fcc-xl.jpg


While were talking power section caps, can someone please confirm my suspicion that this other .05 1kv cap, which is connected to the PT primary and polarity switch (it's a US import model) is just the equivalent of the "death caps" on 60's Fenders? What's the common practice here? Disconnect, replace, or let it be?

https://www.re-wind.net/risa/i.php?/upl ... 190-xl.jpg

Thanks for the help!

RedRox
New Member
Posts: 2
Joined: Tue May 07, 2019 4:48 pm
Just the numbers in order: 13492

Re: Power Section caps (1972 SL restoration)

Post by RedRox » Tue May 04, 2021 1:12 am

Nevermind about this topic. It took three months to get approved and posted. Long since figured out and moved on.

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