VAX DECserver

Fri, 18 Sep 2026 16:29:36 -0400

I got a few of these DECserver 90TL units. They are a neat little device, with 8 RJ45 serial ports on the front, a 10Base-2 port on the top, a power port on the back and also a “hub port” which I’ll gloss over for now.

Power

The power is DEC-custom, 7-pin Mini-DIN and takes 5.1V. This site has the pinout information. Adapters on eBay go for about $60.

Terminal Data Cables

I made special cables to go from the RJ45 serial ports to the DEC MMJ ports on my VT420s and other terminals. I had to get an MMJ crimper, which I also found on eBay, from a company called Paladin. The pinouts are:

Vax on Symbolics LISP Engineering

VAX DECserver

Power

Terminal Data Cables