Mystery box

[Director]

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.
> 
>