Ohio Scientific's Rescued...need help/info!

From: Bill Sudbrink <wh.sudbrink_at_verizon.net>
Date: Tue Oct 8 23:22:00 2002

> Last night I rescued two Ohio Scientific systems:

Congrats!

> A challenger C1P and

Plastic or metal case?

> A Challenger II (which was a MUCH bigger box, and had a matching big,
> heavy dual 8" floppy cabinet).

Blue/black or tan/brown?

> The haul also included an ADM-3A terminal (always wanted one of
> these), and a dual 5 1/4" floppy cabinet (don't know which system
> this goes to).

I would like to see a picture of this. It's probably not OSI.

> I got no documentation, no software or anything
> (these were all picked up from a curb-side garbage pile!!)!

Lucky, lucky lucky! Where?

> Any pointers to documentation, software, specifications, etc??

I have lot's of docs, etc. for OSI. OSI is the principle focus
of my collection.

> I've read the stuff on a careful process to power-up an altair...does
> this apply to these systems too (I don't have much in the way of
> electronic test equipment or power supplies).

OSI uses regulated supplies. Generally, they either work or they don't.
I've never had one zap anything... but anyway, the 5 volt supply in the
C1P is easily disconnected from the main (and only) board. Put a dummy
load on it and check. 4.7 to 5.3 is cool.

The Chal. II will probably have a PowerOne supply (again, very reliable
in my experiance). Pull all of the cards from the "fatherboard" (you'll
need to anyway, just to reestablish contact) (the order of the boards on
the bus does not matter) and put dummy loads and check voltages on the
following pins (counting 1 to 48, top to bottom):

23 - +12
24 - -9
25 - +5
26 - +5
27 - gnd
28 - gnd

> Man...I hate to think of these classic's going landfill...... gotta
> save 'em all!

Contrats again!
Received on Tue Oct 08 2002 - 23:22:00 BST