Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!uwm.edu!gem.mps.ohio-state.edu!usc!merlin.usc.edu!aludra.usc.edu!dickson
From: dickson@aludra.usc.edu (Jeffrey Dickson)
Newsgroups: comp.sys.apple
Subject: Mystery Card
Keywords: interface
Message-ID: <5492@merlin.usc.edu>
Date: 4 Oct 89 04:32:50 GMT
Sender: news@merlin.usc.edu
Reply-To: dickson@aludra.usc.edu (Jeff Dickson)
Distribution: usa
Organization: University of Southern California, LA, CA
Lines: 18

I've exhasted the resources of my local BBS's on this problem. Perhaps someone
out here can help me.

A friend of mine picked up a card at an auction marked PERFECT 80. We can't
seem to figure out what it does. It does NOT fit into the 80-column expansion
slot on the //e but instead in the 1-7 interface slots. There is no manufac-
turer or date marked. The card has two sets of pins marked IN and OUT. Each of
these, has two pins identical to the speaker jack on the motherboard.

We connected a voltmeter to the OUT pins and messed around. Typing PR#x (with 
the card in slot x) made the pin voltage jump from 0 to 0.665 VDC. The display
was disabled, as expected. As we banged on the keyboard, the voltage rose by
0.001 V for each 10 characters; up to a max of 0.775 V. I thought is this some
kind of ancient 80 column card with a composite output. Typing home did not 
lower the voltage however. Entering a large number of RETURNs did make it drop
in discrete steps back to its original 0.665 V.

            Anyone have a clue ????????