On Mon, 23 Jul 2012, Kevin Reynolds wrote:
Hey guys and gals,
I have tried and failed to get a successful connection between my uvax
II and a pc rs-232 serial port. The H8751-B didn't seem to work, so I
pulled it off and wired my own MMJ-DB9 connector. I have tested the MMJ
cable, and it works flawlessly.
For my connectors I have followed "The Cable" documentation at
(chucks house of
vax), under "The MicroVAX II" section but it hasn't helped. I have
tested the MMJ-DB9 connection from my uvax III consoles and from the
microvax 3100 and it works fine, so I think the PC side is working
The pinout for the cable at Chuck's House of VAX is correct. I just opened
up the connector shells on my own cable which I assembled more than 10
years ago and verified that it matches the information given there.
Your other option would be to use a H8571-B on the VAX side connected with
an MMJ cable to a H8571-J (or equiv.) on the PC side. While the two
adapters are both DE-9, the pinouts for each are very different.
I've used both solutions for my own systems, and I used to make and sell
H8571-J "work alike" adapter cables on eBay (DE-9F adapter with crimpped
pins to 6P6C jack, wired the same as a H8571-H, along with a 6P6C to MMJ
modular cable; I sold 100s of those things).
If you'd rather not butcher an MMJ cable, I'd suggest finding an H8571-J
adapter (useful with an MMJ cable for many other purposes as well). If
someone else can't supply you with a second hand H8571-J, I do still have
some NOS inventory (still in the original DEC bags) stored away (but not
/too/ difficult to get to) but I paid a good bit for them so I can't just
give those away.