Rankins@DOCKMASTER.ARPA (12/01/87)
Does anyone know where I could find schematics and/or plans for a slot
expander for the IIe/gs? What I need is something that plugs into slot
2 (or any slot 1-7 for that matter) which leads to a box with 4 slots in
it and a rotary switch which will let me select one of the 4 slots to
use. The reason I need this is because I have three different cards
which need to go into slot 2, and I don't enjoy having to keep opening
my IIGS and swapping cards every time I want to use a different one. I
know such a thing exists because I have seen one in a computer store,
but they wanted $150 dollars for it, and to look at it, there really
isn't much to it (a box, a cable with a 50 pin card on the end, 4 slots,
and some resistors and capacitors). My father-in-law and myself have
already built a prototype of one, but I guess we're missing some minor
point, because it doesn't quite work right. When we tested it with a
modem card, we got a dial tone, but it didn't dial correctly (the touch
tone beeps were lower in pitch and had some static - the dial tone
continued).
Anyways, this is what we've put together:
four slots - the +5, -5, +12, -12 lines are switched
by a four way rotary switch
ribbon cable from the box to a 50 pin edge connector
capacitors on the +5 lines of the 4 slots
(this is as specific as I can remember as I don't
have it with me right now)
When we put a tester on it, it seemed to be getting the proper amount of
power to all four power lines. Right now, we're somewhat stumped. If
anyone can suggest anything or point us to where we might find plans
and/or schematics for such a thing, it would be greatly appreciated.
Thanks in advance,
Ray
p.s. - if anyone knows of any good books or magazines that give plans
for do it yourself computer hardware projects, please let me know. We
really enjoy working on such things.
Rankins@Dockmaster.arpa