atcomsystems.ca/forum Forums Other TDM Phone Systems 1A2 and Comkey Telephones & Systems Can you guess what this is?

Excellent! I've got a Melco unit and a 6B I've used and they'll both light a lamp on the key system, but neither of them will take a call off hold.

I'd be interested.....

Sam

Sam, this is an exact clone of the Melco S64-1 A-lead adapter. If you have one of those already and it doesn't work, this may not help you. That being said, I'd be interested to see how you have them wired. I think it was customary to feed DT into these from the station side of the line card and when I wired it that way, it only partially worked. I got line lights and whatnot, but it refused to take a call off hold. The secret was to get DT from the CO side of the line card and then it worked fine. I have a regular POTS line, and three VOIP lines feeding my 1A2, and all four I can take calls off 1A2 hold as long as the adapter is wired on the CO side.

Of course, the more I think about it, there's also a chance that the Melco units that are out there are all pushing 30+ years old and the components have surely all drifted in value. They have three electrolytic caps on the board and those things age as gracefully as milk. So, maybe the one's I'm making with fresh parts might be just enough to work again..... Can't hurt to try.

One thing I haven't sorted out is packaging. It's just the bare board and a short piece of cat5. I could drill the corners, and with some standoffs you could just screw the thing to a backboard. My next iteration of these, I'll find some cost effective cases and design the board to fit them so it can be enclosed and pretty. The other thing I'd really like to do is find a board mounted 8P8C jack and design that into it so you can just plug it in. Dressing the cable and soldering it in is tedious.

Another thought I was having was making multiple adapters on one board. That way if you needed more than one it wouldn't eat up a bunch of real estate on the backboard.

Neat!!

Would this https://canada.newark.com/stewart-connector/ss-6488s-a-nf/connector-rj45-jack-8p8c-th/dp/56AC3197 work for you as a board mounted jack?

Chris -

I seem to remember something about using CO Dialtone. I looked, my Medco unit apparently bit the dust some time ago (who remembers when) and all I’ve got in are WECO or NE 6B units.

Let me know if you ever go into production.

Nice job!

Sam

I've made half a dozen so far. PM me and we'll see about getting them into service. I have the stuff to make 50 of them, so they're will be plenty.

That's exactly the type of jack I was looking for. I'll have to see if my board design program has the hole layout for that so I don't have to wing it.

Sam, if you still have the dead Melco, let me know. I can rebuild it unless its charcoal.

Thanks Chris, I'm sure it's long gone.

Sam

I just noticed that because I am in Canada my search brought up a Canadian source which I put in the line above. I just checked Digi-Key in the US and they have the same Stewart Connectors on their web site.