Path: utzoo!attcan!uunet!husc6!bbn!uwmcsd1!ig!agate!ucbvax!EMX.UTEXAS.EDU!mknox
From: mknox@EMX.UTEXAS.EDU (Margaret H. Knox)
Newsgroups: comp.sys.misc
Subject: When is S-100 NOT S-100 (Ithaca Encore)
Message-ID: <8805220035.AA19312@emx.utexas.edu>
Date: 22 May 88 00:35:43 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
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My thanks to Mr. Peter Collins (whose reply to me bounced across half
the hosts in the US) for pointing out the reason for the *CAUTION*
on the S-100 cards in an Ithaca ENCORE system.

S-100 systems normally put out filtered (but unregulated) voltage
on the power lines (for instance, > 7 volts DC for VCC).  This is
then regulated on each S-100 card, distributing the heating and 
allowing the use of the small 1 - 3 amp 7805-type regulators.  The
ENCORE regulates the voltages AT THE POWER SUPPLY.  The boards are
standard S-100, but the place for the regulators are bypassed (shorted
across)

As Mr. Collins points out:  Put an ENCORE card in a normal S-100 chassis
and it will make fireworks!