atcomsystems.ca/forum Forums Other TDM Phone Systems 1A2 and Comkey Telephones & Systems 1a2 Project--Beginning Stages

Good day, everybody! I'm very exited to be starting this journey down 1a2 avenue, and hope many of you with your expertise can make sure I'm on track. Bear with me as I give you a little bit of history, as it is relevant to the 1a2:

I live in an old 3-story Victorian in the City of Niagara Falls, NY, where there are some big old houses. The house still has tons of low-voltage wiring for intercoms, speaking tubes, a dumb waiter (not my wife), and call bells. Obviously a very 'connected' house for the turn of the century.

Well, it was my dream to have a phone in almost every room. And now I do. I have a Mitel SX-50 powering 24 rotary phones with MOH and all the fun things you can do with a PBX, with no phone newer than 1964 (most from the 30's and 40's WE, S/C, AE, etc...).

The system works great, and I love it. I also love 1a2. I also have 2 complete KSU's! one 13-slot and one 6-slot. The 6-slot just came out of service last week, when I pulled it off the wall of a guy's business. The whole board, 66's wired, Incoming CO block marked. Pretty much plug and play. However, I have had the 13 card slot KSU for years (out of an old military installation. I'm in the Air Force, and got to know the COM guys pretty good. OH, and BTW, did I mention that I have dozens of AUTOVON phones and system parts? Don't see those much anymore! Full AUTOVON phones, Rotary add-ons for TT, TT add-ons for Rotary phones, extra keypads).

Sorry, I get exited about this stuff. In any event the 13-card KSU is all there, with power supply and interruptor, with a MOH card (LC-400E?). I took pictures but am unable to upload them here. Can you upload pictures?

IN ANY EVENT, HERE's THE PROJECT:

1. To install 1a2 Key System, with CO lines coming from my PBX. Rightfully, if I had a 30 button call director, I would have 24 extensions to connect to (well, depending on how many slots I had, right?). All the extensions have a dial tone, so I figured that this would be a cool way to have a working 1a2 with lots of lines! I would then have substations with less lines from the standard 5 button WE rotarys.

2. Essentially, it's redundant, I know. But why not? If I have all this free equipment just sitting there, might as well hook it up! Any pointers, comments? I have pictures if anyone needs to see them. My other question is: Since I have a 13 and a 6 slot KSU, can I hook both of them up to get 19 slots? A lot of wiring, I know, but is it possible?

3. Any drawbacks you see to this? I'm very exited about it, and trying to learn as much as I can about it. I don't have the BSP's, but if anyone has a link or idea of where to start more information, that would be great.

I know it's a lot at once, but thanks in advance!

-Bob

I see nothing wrong with your mindset. The only concern that I'd have is that some line cards won't operate behind PBX line circuits. You mentioned that you have LC400E cards (Brand-Rex, I assume?), so you'll be fine with those working behind the SX-50.

Keep in mind that although they call the LC400E a music on hold card, it really isn't that simple. Yes, a music source can be connected to pins 3 and 18 of the card slot, but you need to ensure that the slot doesn't have -24VDC talk battery factory-wired to them. Also, for MOH, you need an isolated music source for each line card (using an ITT 403A card, for example) or the parties on hold will hear each other. I would imagine that in your case, this won't be an issue.

Ed,

Thanks very much. I still have tons of questions, but getting all the preliminary stuff out of the way. They are all K400E line cards with the exception of the one LC400E card, which I'm really not concerned about as of yet. The K400E's shouldn't be an issue, should they? Also, what do you think about putting both the 13 and the 6 KSU into service together for more extensions? Just more wiring, right?

To post pictures, just use a site like photobucket to upload, then paste in the IMG tags into your post.

art1339 1a2 Project

Here are some pictures of what I have (link above), including the Mitel SX-50 system that's already installed. There's also a nice 5 button add-on that I can use on some of my older 4 wire phones, too.

Hope this helps give you an idea of what I currently have. I also have about 4 5-botton phones to use on this, too. What do you think about this call director? (link below) Good for what I'm looking at doing, provided using both KSU's together is feasible?

Ebay call director

First, tying two 1A2 systems together is a prescription for trouble, unless you have some really knowledgeable help.

Second, why would you run the C.O. lines through the SX50 and then through the 1A2?

Third, keep in mind 1A2 phones require 25 pair cable. And copper is getting $$$!

When I lived in Salina, KS I had a 3 story, full basement, Prairie Four Square, built in 1925 that I loved! I put in an old NEC 1648 EKS with 3 Key phone cards and 1 Analog phone card (For the computer modem.) I would have used an SX50 with Supersets, except that was 12 years ago and SX50's were still being sold new! But never, in my wildest dreams, would I have considered a 1A2 behind the SX50! If you really want keyphones, check with our host here regarding Superset 4's. They're cheap and the circuit card for them is as well. Each Superset card supports 8 Superset's. Alternatively, the Superset 420 is a later unit, but the card for them is NOT cheap, and is hard to find! Oh, and the supersets run on 1 pair, just like the analog phones. JMHO

You can link both KSUs. Make sure that both power supplies are grounded to the same source. If they're not then you;ll have a great deal of trouble taking lines off hold, etc.

Put the incoming CO lines on the PBX and then connect the extensions off the PBX onto the 1A2.

The Autovon phones won't (to my knowledge) work without an Autovon CO. As I recall they were 4-wire (1 pair each Transmit & Receive) and not 2 wire (Tip & Ring). They're still pretty slick. If you'd like to trade or sell, let me know.

Good luck with your project and ask away for any help you might need.

Links to BSPs are available. Let us know which ones you need and we'll do what we can.


Sam

I have been working on 1A2 for the last 50 years or so, and I can be of help with wiring advice and parts that you may need. Just contact me by email using the info in my profile, or this:

info (at) SIBTA (dot) com

or these:

631 - 749 - 0100 office
866 - 749 - 0100 toll-free


Connecting two or more 1A2 systems together is trivial. All you need to do is connect the Signal Grounds of all the power units.

I am also familiar with Autovon phones and have a few in my collection. I can provide simple drawings that allow using them on 2-wire lines.

Arthur -

Autovon on 2 wire! You never fail to impress me!

Sam

Do you have each room wired with a 25 pr cable?