13 Jul
2005
13 Jul
'05
4:01 p.m.
The connector is a DB-37, used mostly for RS-499, but this does not look
like that kind of device. The other common use for this connector is in
Analog/Digital control devices. I agree with the comment that it looks like
a log display that varies from + to -. I am guessing, of course, but I
suspect that the thumb switches on the front allow the selection of one of
several analog signals on the DB-37 connector and that the unit digitizes
the signal on that pin and displays it on one of the lights.
It is definitely a one of a kind or a very short production run since it is
made on perf board. Even for a few copies most people would make a printed
circuit.
Gil
-----Original Message-----
From: cctech-bounces at classiccmp.org
[mailto:cctech-bounces at classiccmp.org] On Behalf Of Tom Jennings
Sent: Tuesday, July 12, 2005 5:18 PM
Cc: General Discussion: On-Topic and Off-Topic Posts
Subject: Re: Mystery box
On Tue, 12 Jul 2005, Stefan wrote:
Can anybody tell me what this little blue box is
?
http://www.xs4all.nl/~rimmer/mysterybox/
There is no way to tell what it is precisely from photos,
make a schematic and maybe we can. It's obviously hand made.
Well it's got a 74181 4-bit ALU, and a demux and flops, but a
lot of LEDs, so maybe it calculates CRCs, checksums, or
tallies input pulses, or counts complicated events. There's
enough glue in there to make a decent little processor-like
state machine with ALU, so it could be a very clever little
box, but it probably solves some specialized niche function,
and without knowing where and how you'll likely never know.