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From: wkb@cbsck.att.com (William Keith Brummett)
Newsgroups: rec.audio.high-end
Subject: Re: Amp Modifications/Upgrades
Message-ID: <7189@uwm.edu>
Date: 24 Oct 90 12:49:49 GMT
Sender: news@uwm.edu
Lines: 39
Approved: tjk@csd4.csd.uwm.edu


    In article <7133@uwm.edu>, versatc!peter@apple.com (Peter Tapscott )
    writes:
    > Does anyone have a source for large, high
    > voltage electrolytic capacitors that could
    > be used for a power supply for an amplifier
    > of about 200 watts?
    > ...
    > 	10,000 uf @ 63 V (Not bad)

    Well, until a few months ago, *I* was a potential source.  I had a bunch
    of surplus Sprague Powerlytic computer-grade caps (bright blue cover).
    They were chasis-mount, and the largest were about the size of a Sapporo
    beer can (~2.5" x ~8").  They were in two's and four's, and ranged up to
    60,000uf @ 75VDC, as I recall.  I sold them at the Dayton Hamvention for
    about 2 bucks apiece.  I saw other similar caps there for similar prices.
    I suggest you check out the next nearby electronics flea market or
    computer fest.
 
    > What are peoples opinions on using a 100V
    > cap for a 90V DC voltage?  The next step up
    > in voltage is 200V.

    Someone once told me that you could push the Spragues a bit above their
    rating, but to be real careful about japanese caps -- they just barely
    make their specs.  Be conservative.  I once connected a small cap to a
    circuit backwards.  Have you ever had a 12-gauge shotgun shell go off in
    you face?  Trivial in comparison.  I was picking bits of paper out of my
    hair for hours.  Good thing I wear hardened glasses.

    > Is it necessary to use TSNH instead of TSU?

    Dunno.  -- Keith

-- 
    | W. Keith Brummett          (614) 860-3187          AT&T, Room 3B-202 |
    | att!cblph!wkb                                    6200 East Broad St. |
    | or, wkb@cblph.ATT.COM                        Columbus, OH 43213-1550 |
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