"No name" S-100 computer

From: dave dameron <ddameron_at_earthlink.net>
Date: Fri Jun 26 00:48:02 1998

Hello All,
I have been working on a "no name" S-100 computer for some time, and finally
have gotten it to work! No name =
Godbout 12 slot motherboard. Cards:
Ithica Audio Z-80 card
Seals 8K ram + Godbout 8K (2102 type ram's)
Processor Tech CUTS (Cassette tape)
Processor Tech GPM (1K ram + ROM board, 1 2K ROM installed)
Vector Graphics Flashwriter (16x64 character display)
Homebrew card (Input FFH port, etc)
All in a modular blue/white metal box with only a lighted power switch and a
reset switch.

AFAIK, the parts that were not originally mine were not "abused", but was
surprised at how much was wrong:
1) The op-amp in the motherboard active terminator was bad.
2) A cap across 5V in one of the RAM boards was shorted. The 2102 rams on
this supply didn't like ~0V power, but TTL address and data signals. Luckily
they were socketed, and still available fairly cheaply.
3) 3 other 2102 rams were bad. Some on the "GPM" board were marked only "DS9408"
4) There was a "pready" signal conflict. Don't know how it was run with this
problem?
5) Bad transistor in the keyboard.
6) 1 or 2 bad 74367 ic's
7) Bad solder joint for one memory pin on the GPM board. It was OK 90% of
the time...
8) Bad 4013 ic in the CUTS board- receive data path.

Along the way, built a S-100 test jig that was very helpful - one powered
edge connector with data, address lines provided by switches, latches, etc.
+ led's to view data lines. I could test memory chips one at a time with it,
find where cards were in address space, until I could get the system to run
with a serial terminal (My Heath H-19) and monitor software for further
debugging.

Finally I loaded Proc. Tech. Basic5 the first time! That cassette tape is
about 22 years old. Also "Lunar".

My questions:
The Processor Tech GPM board I have no documentation, other than what I've
figured out. It isn't that complicated. Does anyone have any, such as what
are the ROM jumper choices and dip switch positions. (I've figured out about 4)

Is there any archive for CUTS software? In the late 70's when I lived in the
San Francisco Bay area, there was the "SOLUS" user's group.

The third is more general, what determines the value?
Obviously if this was a SOL-20 or in a IMSAI box, it would be worth much
more on Ebay as well for collectors. In a literal sense, it is more unique
and I have design documentation for
the mods I've done, dates, reasons, etc. Quess what would be called the fabric.
In some cases that's what has the value. (First prototype, etc.)


In 10 or ? years, how will I pass it along "to the next generation"? I don't
think any public museum would want a "no name" box, and from the museum threads,
doesn't sound like a good idea, anyway. I know no one personally that has
these "old" computer interests except maybe the speculator type, only this
list. Those with private museums, will you be collecting this stuff in say
20 years, or will you be looking to pass it along? To ???
For old radios I can consider the AWA museum, as assume it will be around
longer than any individual, but they probably don't want a lot of homebrew
stuff. The brand names already "restored" radios are too expensive and rare
for me, anyway.
Thanks,
Dave
Received on Fri Jun 26 1998 - 00:48:02 BST