atcomsystems.ca/forum Forums Other TDM Phone Systems 1A2 and Comkey Telephones & Systems Looking to get in to 1a2 key

It was sort of a joke. The tag was rare, but the buyer really wanted the 501, so I "sold" him the tag, with a "free" KSU attached.

I am planning on liquidating most of my 1A2 equipment before I move at the beginning of next year if anyone is interested.

scott_bonk(at)premiertelecom(dot)us.

Scott - When you're ready, post a list of what you have for sale. You might get a few bites.


Sam

I definitely will, thanks Sam! hope you are doing well.

Thanks, Scott. Better then I was.

Sam

So I have an interesting problem with a 400d card from 66', the card will not hold, not even when I hold the relay in to make it hold. I have moved it to a couple different slot and all have lines on them, my other card from 69' works fine after lubing the relays, they are both iss 8. And I ordered 3 more cards on ebay and hopfully all of them are iss 15 ( I asked for them since he had some in the pics), so when they come in ill see if they work fully too.

It's not worth the effort to try to fix line cards... usually. If a line won't go on hold, make sure your A-leads are connected properly and you have a line light when you go off hook on that line. From the sounds of it, you've done this already and have tracked the problem to the card itself. It is more than one relay that makes it put the line on hold, I believe. The other relay that could be faulty is the L relay which is in the metal can. You can't open it, nor should you. That's where the green goop lives. If the problem is indeed the line card, the thing to do is just replace it.

Be wary of the the ebay seller, Cliff. I've bought line cards from him and also asked specifically for Issue 15. My request went completely ignored and I got everything but a 15. He's on the up and up, otherwise. Always ships pretty quick, and usually has some good deals on old 1A2 gear. He probably sold out of Issue 15's ages ago. I only have 5 Issue 15's and they're in use, or I'd offer them to you.

There is a really simple modification to make any other issue of 400D into a 15. It only works with other 400 "D", none of the other letters. But 400D's are a dime a dozen. I got a schematic from another member on how to make the modification, and it involves desoldering one end of one component and adding a single resistor. It takes literally 2 minutes to do and it is completely reversible should you want to. I have to ask if I can share that. I'll let you know.

Putting a call on hold is a very specific, carefully timed sequence of events that must happen in the right order or it doesn't work.

When you push in the hold button the A-leads go open circuit. (No connection). The line key remains depressed and tip and ring are still connected to the network in the phone.

As you release the hold button, the a-leads remain open and the line key pops up breaking tip and ring.

It must happen in this order. A-leads break - then - tip and ring break. If there's a problem with continuity on the A-leads it will not go on hold. Usually, an open a lead will manifest itself as a line key that won't light up when you are using that line on that phone.

The other common hold problem is called false hold. This is where the line puts itself on hold when you go to hang up the phone. This is caused -usually- by the hookswitch being out of whack or being wired wrong.

To properly hang up a line the sequence is reversed; Tip and ring MUST open first, followed by the A-leads. If the switchhook pileup gets bent or damaged this can happen. The other problem is when some "handyman" tries to rewire one of these phones. There are three sets of contacts in a hook switch pileup. One is for the A-leads, and one is for either tip or ring- I don't remember which. When you go off hook, the A-leads make first, then the voice circuit (tip or ring) makes. When you hang up, its the opposite. Tip (or ring) opens FIRST, then the A-leads.

It's one of those things you don't think you need to learn, until you encounter a hold problem, especially a false hold, and you tear your hair out trying to fix it. Been there, done this, have the T-shirt.

Hope this was helpful.

Chris

Also remember, you have an A-lead for each line, but only one A1 lead. A1 is just a ground, and each line's A-lead is just looking for a ground to close a relay. If you have the ORG/WHT pair reversed, only line one will go on hold.

Do you have a wiring diagram for a typical 6 button set? Don't try to wing it if you don't. I could almost recite it from memory and plenty of guys here can recite the wiring for a 30 button call director from memory. Just ask if you aren't sure.

Yes I do have the schematic for the set, and about the 400D mod, ill take you up on the offer, I have a suspicion on what to do for it, ill see if i can figure out. and on the front of the open a1 and 1a leads that was one of the first things I checked. And yes the guy i ended up getting the cards from is cliff. 6 button set pdf