I have a piece of DEC hardware that I got years ago at an auction as part of a lot.  It has followed me for 4 years and I JUST fired it up...it works.

Now I want to find out what it does.  The main box says it is Model: VSXXX-CA, there is no label on the front, just a rocker power switch.  The box is 8cm (3 in) high and each side is about 35cm(13 in).  The box is obviously designed to have a monitor placed on top of it.  It even has foot indentations for the monitor.

On the back there are two DEC mouse ports, a DIN-5 keyboard connector (LK-401?) and a LK-201 keyboard connector.

There are two DB25 connectors (serial port?) label J1 and J2.  

There is a green light with the label D25 above it and 8 red lights (LED) with the numbers 0-7 above them.

There is a rectangular 4x2-receptacle (J4) of unknown purpose and a rectangular 6x2-receptacle (J3) for a plug that leads to separate box.

This separate box is a VSXXX-DA, the copyright says 1978.  It has 2 rows with 4 dials on each row.  Above each dial is a 4-digit LED display that counts from 0 to 4096, when the corresponding knob is turned.  I might add, these are some smooth turning dials!

Since I took my box of RS-232 cables to work, I can't investigate the DB25 ports, so I thought I might turn to you guys.  Any ideas?

jam