Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!swrinde!zaphod.mps.ohio-state.edu!uwm.edu!bionet!apple!motcsd!motsj1!mcdchg!att!cbnewsd!jdu
From: jdu@cbnewsd.ATT.COM (john.d.unruh)
Newsgroups: comp.sys.mac.hardware
Subject: Re: Anyone built SID yet?
Keywords: SID
Message-ID: <13359@cbnewsd.ATT.COM>
Date: 23 Feb 90 13:17:09 GMT
References: <4790@ccncsu.ColoState.EDU>
Reply-To: jdu@cbnewsd.ATT.COM (john.d.unruh,ih,)
Distribution: comp
Organization: AT&T Bell Laboratories
Lines: 20

In article <4790@ccncsu.ColoState.EDU> arvidson@euclid.MATH.ColoState.Edu.UUCP (John Arvidson) writes:
>
>I ran into the same problem... I can't find a source for the ceramic resonator
>and also the quad op amp.  I'd be interested in sources or substitutes if 
>anyone knows of them.
>
>John Arvidson


I have looked at the schematics.  From what I saw, I think that the ceramic
resonator is just being used as the frequency determining component for the
oscillator portion of the circuit.  I don't know of any reason that this
part has to be used rather than a crystal cut for the proper frequency.  After
all, what that part of the circuit is doing is developing a square wave to
clock the next device (don't have schematics handy and don't remember what it
is).  This is frequently done using some inverters and a crystal.  I expect
that some circuit modifications other than just putting in a crystal at the 
proper frequency might be necessary to make it work properly.

John Unruh