atcomsystems.ca/forum Forums Other TDM Phone Systems 1A2 and Comkey Telephones & Systems 1A2 intercom

Hello guys-
I have not done anything with my 1A2 system in quite a while. I was thinking about adding intercom, since I am only using 1 line button on each of the keysets.
I'm using 3 out of the 4 line card slots right now in my 551B KSU.

What all would I need to accomplish this?

Jeff

You can use a 401A or B card in the 4th slot to provide a manual talk path. You would use buttons and buzzers to signal the stations. If you have just a few stations, you could convert the unused line keys in the sets for momentary signaling.

If you want more fun, add a Teltone R10 or R19 (R as in rotary) a T10 or T19 (T as in tone) or a C19 (C as in combination) outboard dial selective intercom. Here's one for the right price and no shipping! Buy it now!

T-10


These provide one common talking path and selective signaling via the dial. You can use the 28-type power unit that's already in the shoebox to power them. You would need a short piece of 25-pair cable with a female amphenol, and a separate 66M50 block on which to terminate it.

The wiring is simple, even for an IT guy like you. (Sorry, couldn't resist)

The convention is to use the Y/O pair for the buzzer in each phone. Use the 18 Vac supply for the buzzers. If they are too loud, use the 10 Vac tap. You can also use Uncle Arthur's Patented Really Cool Sounding Buzzer Method, and put a diode in series with the buzzer supply. That makes the buzzers burp instead of buzz.

Would you happen to have a 401A card in Uncle Arthur's Patented Barn?

A few years back, I rigged a doorbell button at the top of the stairs to light the 6th button on my keyset and sound the buzzer.

I used a separate power supply, though.

I just edited my message. Take a look at the T10 intercom in the Ebay link.

I can send you a 401, if that's the way you want to do it. The dial selective way is more funner, though. And actually takes less wiring, in the long run.

I think I would like to start simple with the 401 card.

I'll dig one out. Is it your birthday again?

Have fun with the button and buzzers.

Arthur, my birthday was a month ago yesterday :P

Bill, I already have a button and buzzer connected in one of the keysets, and I think I have some more buzzers in a box.

I agree with Arthur, the dial intercom is more fun and won't chew up your last slot, but have fun in either case.

You could also use the dial intercom to access a PA system.

What! You don't have a PA system in the house? How about a Spokesman or Orator? Use one (or more) of them as mini PA systems.

Sam

Oh yes, I have a full PA system in the basement, complete with paging through my Inter-Tel, Norstar, and Panasonic systems.

Well, Excuuuuuuuuuuuuuuuuuuuse me!

Mostly just for listening to music through my laptop :P

Thanks to Uncle Arthur, I now have a 401A card installed in my shoebox and it is working!
My next question is: how do I get a buzzer working on the intercom key?

You need to assign a spare line key (converted for momentary signaling by removing the lock screw) or add a 551A key, on the side of the phone.

Then you need to move a couple of wires around in the set. You need SIG GRD to come into the set on the BRN/YEL lead. Then wire that to one side of the signal button. The other side of the button becomes a signal lead that, when grounded, looks for the 10Vac buzzer battery on the buzzer at the distant end.

In the other phone, the buzzer gets put on the OR/YEL pair. One side (the Orange lead) gets put on 10Vac buzzer supply. The other side is tied to the signal lead discussed above.

These connections are all done at the MDF using cross-connections. Use solid black for ground, solid red for buzzer battery.

Note that "SIG BAT" on a typical power unit is ambiguous, and is actually -24Vdc. You need an A-C supply of 10 Volts. On a 20B2 supply, there is a screw terminal for 10 Volts, that is independent of the 10Vac LAMP supply. In a shoebox, however, you access the 10Vac by adding a wire to the LAMP BATTERY supply ("LB") on the 66 block in the KSU, down at the bottom right side.

BSP for 565HK set

BSP for shoebox

BSP for buttons & buzzers

Thanks!
The 2 keysets I am working with are 2564.
On the first set, I have already unlocked the 6th key and when I press it, the lamp lights and I get talk battery. It currently has a buzzer on the yellow/green pair.

The second keyset already has a buzzer in it, also on the yellow/green pair, connected to a doorbell button at the top of the steps, and a separate transformer. I've already removed the screw on the 5th key for this set. I have to finish these cross connections and see if I get talk battery and light (I expect to)

Perhaps I will give my Uncle a ring one evening after work this week.

Jeff

I will report back!

You're getting ahead of yourself.

Put the screw back in the 6th key. It needs to stay locked down for talking. The light should come on and stay on for the duration of the call. You need another, separate, button, converted for non-locking, to do the signaling.

If you don't have a spare button, you need to add a 551A outside the set, or convert to a 830 set, or...

That's why we recommended that you use a Teltone dial selective intercom unit from the git go. It needs no extra button for signaling.