sundance-communications.com/forum Forums Other TDM Phone Systems 1A2 and Comkey Telephones & Systems Use of bell for intercom audible

Hi everyone,

I have a WECO 551C KSU with an external Tone Commander rotary/TT intercom, its all set up and working fine. I'm currently using 10VAC buzzers for intercom audible in the 6 button sets and in a couple 2500's (that I added 10VAC buzzers to the yellow/black pair and I use the 2500's for intercom only). The 551C has a ring generator (currently not used).

So in the workshop and the garage, the buzzers are not loud enough to hear with all the background noise, so I aim to hook up a ringer (bell) to these 2 stations. What is the best way to send ring voltage on intercom contact closure...

(1) Put a 10VAC relay on the contact output of the Tone Commander, and then run the ring generator thru the contacts on the 10VAC relay?

(2) Discontinue all use of 10VAC for the Tone Commmander input and use ring generator as direct input to the Tone Commander audible? (Of course I will have to discontinue all use of 10VAC buzzers in all stations).

(3) If I do (2), can I send the ring generator output from the Tone Commander down to the tip/ring on the 2500's to use the ringer (bell) of the 2500's (instead of using the buzzer)? If I do this will this damage the A-Battery circuit (from the 551C) that I'm using for talk power on the intercom circuit? And of course, what happens to the ear of the poor 2500/2565 user when the phone is off hook and someone else dials an intercom station? I'd like your opinion if this option (3) is doable, a nonsense case, or just a real bad idea to be avoided at all cost.

Thanks, -Stryder

If you don't need the ring generator for the common bell than I'd go with #2. You can't send the ring voltage down tip and ring when you're using the talk battery, of that I'm pretty sure. If I'm wrong about that someone will correct me, I do think you'd blow a fuse before you ever hurt the filtered battery though. Been a long time since I use 105 volts out of a tone commander so I really don't remember, the wiring scheme is on the side so that should help you.

Bill's right. #2 will work best, especially since you already have the ring generator. You are right about the 2500's though; you can't run ringing across Tip and Ring for the intercom. You'll need to continue using the second pair and just wire it to the ringer in the set instead. The connections are as follows:

Black: Goes to black ringer lead on any blind terminal;
Yellow: Goes to red ringer lead on any blind terminal;

Make sure that the slate/red and slate ringer leads (if present) are connected to terminals A and K on the phone's network.

There's nothing wrong with connecting ring voltage to the RN and RG inputs on a Tone Commander intercom; they are made to permit this.

Also, remember that tip and ring of all intercom stations come back to a common tip-ring of the intercom, so if you tried this, a call to one station would have the potential to ring all 2500's connected this way.

As for the loud ringing when the phone is off-hook in use, there is a set of switch hook contacts that can be rewired to disable the ringing on most 2500 sets when off-hook.

Of course, you could keep it simple and buy loud ringers that work on 10-12 volts AC in the loud area.

I like your idea of the 10 volt ac bells, wish I'd thought of that.

First he needs the ring generator if he wants selective ringing on a 551. What I would do is make two spare buttons on a 6btn to ring the two stations if they are free. Kinda like a speed dial.

Keep the Tone commander for the SLT. Like Ed said you can Have intercom ring or intercom buzz. But if you choose to have Intercom Ring and selective ringing You will find it much easier to use the ring generator as the input to the rt1900. The common audible input would be much more of a hassle to achieve both intercom ring and common audible. Just my thought's but I would like to know a bit more.. I like the combination of using both the ring generator and common audible idea. Yes you can send the the ringing though the RT for intercom ring

But don't try to take RCRG on a common and send it to the rt 1900 for intercom. This is when the ring generator is needed.

Ed's idea of the 10v bells solves all the problems, in my opinion.

Yes and no, He has the 105 ring generator so wire it
and change leads in the set. No other equipment or relays would be needed. He just wants a few SLT to ring on intercom.. Remember intercom ring or intercom BUZZ? When you need a ring generator. Dial Buzz some station's and Dial Ring others. Easy

Ed A to K and K to A remove the condenser

Nope don't remember that, but it has been a long time. I only remember doing either or not both. Anyway what could be easier than going to the hardware store and getting a couple of 10v bells and just mount them by the connecting block? He's already using the black/yellow for the buzzers. I'm sure there's more than one solution.

To talk about how I would give this user ringing to station and buzz back... can happen with a 551 with ring generator and rt1900. I have wired a few to do this. You can never learn enough about 1A2 and it's possibilities. One can never learn enough about the given concept electrical ideas an old one's in itself being part of a rt 1900 era. Why not dial and turn on the lights
or open the garage door? After all there 19 relay paths.

RT36 even better.

The new RT 96000 microwave tone commander relay. On sale now! With remote notification to eject.

Some days I think they used just a RT 36 to land on the moon.