Xref: utzoo rec.audio:7523 sci.electronics:3471
Path: utzoo!utgpu!attcan!uunet!lll-winken!lll-tis!helios.ee.lbl.gov!pasteur!eros!max
From: max@eros.uucp (Max Hauser)
Newsgroups: rec.audio,sci.electronics
Subject: Lowering power-supply impedances (Re: Homebrew audio equipment)
Message-ID: <4740@pasteur.Berkeley.EDU>
Date: 28 Jul 88 19:01:52 GMT
References: <1075@gethen.UUCP> <6315@bloom-beacon.MIT.EDU> <118@luna.UUCP> <5741@pogo.GPID.TEK.COM> <2627@kitty.UUCP> <61833@sun.uucp>
Sender: news@pasteur.Berkeley.EDU
Reply-To: max@eros.berkeley.edu (Max Hauser)
Organization: U.C. Berkeley EECS / Cornell U. School of EE
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In article <61833@sun.uucp> klein@sun.UUCP (Mike Klein) writes:
| 
| More important than the ampere-hour rating will be, as for any power source
| you are using, the output impedance.  ...

Well, Mike, you're right, of course; but separating the supply-impedance
issue from the ripple issue is no small accomplishment.  And there are of
course the incidental but possibly vital benefits of not having all of
those 60*N Hertz AC magnetic fields around.

Besides, one can always lower the *DC* output impedance of a supply as well,
very satisfactorily, with a little series regulator.  Common-emitter, of
course (both for low voltage drop and, more important, to place the 
dominant pole at the output, the key to success).

Max Hauser / max@eros.berkeley.edu / ...{!decvax}!ucbvax!eros!max


"The ghost of Baron Rudolph von Guggenheim, the 16th century nobleman
murdered by the Countess Rowena DuBois and her lover (believed to be the
Duke of Norwood), falls into Edna's bean dip."   -- The Far Side, 10/85