Silver Mica Alternatives

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ViperDoc
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Silver Mica Alternatives

Post by ViperDoc »

I'm struggling to find a 500 pF capacitor in my stash that isn't noisy. I've got black and maroon (CD17) caps and they're all quite noisy when I probe their output leads. Anyone have a nice alternative? Series 1 nF film caps?
Just plug it in, man.
thetragichero
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Re: Silver Mica Alternatives

Post by thetragichero »

i usually just use ceramic for pf values
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Stevem
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Re: Silver Mica Alternatives

Post by Stevem »

What do you mean by " noisy when I probe their output leads"?

Even a single length of wire connected to a input grid will make noise when it's moved around!
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ViperDoc
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Re: Silver Mica Alternatives

Post by ViperDoc »

Stevem wrote: Mon Aug 15, 2022 9:56 am What do you mean by "noisy when I probe their output leads"?

Even a single length of wire connected to a input grid will make noise when it's moved around!
My tone stack treble cap is silent on the plate pin, starts to get noisy just on the other lead to treble pot input. Same cap on a bright switch sounds like Star Trek (DC to ground). Not sure how normal that is.
Just plug it in, man.
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bepone
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Re: Silver Mica Alternatives

Post by bepone »

i dont understand the question too. :P
if capacitor is in question for creating the noise, isolate it, wrap around copper foil, and ground the foil, then will not produce anything.
but for sure the question is for some other problem..
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dorrisant
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Re: Silver Mica Alternatives

Post by dorrisant »

I have switched from mica to ceramic for almost all applications. Mica seems too harsh. Ceramic seems to be grainy, in a good way..
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bepone
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Re: Silver Mica Alternatives

Post by bepone »

me too. just finished to refresh one bandmaster from 68'. someone put silver mica in bright position! horrible! scratching the glass with the nail sound!
installed ceramic immediatelly returned to musical again
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ViperDoc
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Re: Silver Mica Alternatives

Post by ViperDoc »

I'm going to try some ceramics.
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maxkracht
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Re: Silver Mica Alternatives

Post by maxkracht »

I've been using 470pf 1kv vishay film caps. They are orange, so you know they sound good... BFC237524471 shortish leads but fine for most stuff. There's a yellow axial vishay cap which I have misplaced the part number and the regular 2kv ceramics in my parts bin, both work well.
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