Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Path: utzoo!mnetor!uunet!husc6!psuvax1!vu-vlsi!cheung
From: cheung@vu-vlsi.UUCP (Wilson Cheung)
Newsgroups: comp.sys.amiga
Subject: Re: ASDG Fast ram chirps?!
Message-ID: <1077@vu-vlsi.UUCP>
Date: Mon, 24-Aug-87 08:58:25 EDT
Article-I.D.: vu-vlsi.1077
Posted: Mon Aug 24 08:58:25 1987
Date-Received: Tue, 25-Aug-87 06:55:01 EDT
References: <8708211723.AA10752@THYME.LCS.MIT.EDU> <7066@steinmetz.steinmetz.UUCP>
Organization: Villanova Univ. EE Dept.
Lines: 10

Why chirping noises?
The mini-Rack C has a very simple power supply just sufficient to support
a majority of Zorro-I type boards without drawing power from the Amiga.  When
any device accesses the address lines of the Amiga all power sources will 
experience brief Mhz type power surges as digital gates switch on and off.
A more expensive power supply wont reflect these surges too much as noise.
As to why Mhz type surges produces audible Khz type sounds you'd have to
refer to Mr. Fourier Series and Transform for the accurate answer.
                                Wilson Cheung