atcomsystems.ca/forum Forums Other TDM Phone Systems 1A2 and Comkey Telephones & Systems Use of bell for intercom audible

IA2 is a pain in the ass but you can build accommodations with needs. First of all going to the hardware store to get some 10v bells at what cycle?

With a rt 1900 he could dial and close a contact with conjunction of another relay. We are looking at 17 cycles and not ac of 60 or even through a transformer,

Charlie, I think the original poster's complaint was the buzzer signaling on two sets in the loud shop area. The buzzers are already running on 10 volts AC at 60 cycles. A regular bell like those used in elementary school science class experiments would work on 10VAC, 60 cycles with no problem.

Pretty quick and easy solution for just a few bucks. The existing buzzers in quieter areas can be left in place and the common audible ringing can also be left as-is.

I like your idea of controlling garage doors, etc. with 1A2 intercoms, in fact I used to do that with my system at home. Very handy!

What is an rt 1900?

Hi Bill, Ed and Charlie,

Thanks for all your suggestions.

Ed does make a good point that the main complaint was not being able to hear the buzzers in a couple locations. You have all offered several good options.

Charlie> Remember intercom ring or intercom BUZZ?
Bill> Nope don't remember that, but it has been a long time. I only remember doing either or not both.

Doing both is an ineresting idea. I'm not sure I can do ring on intercom station A and buzz on station B since the Tone Commander is indeed a RT-3600,,, the audible input shares a common ground with one side of all 36 station relay contacts. If each contact had 2 conductors coming out thru the AMP connector (to the 66 block), then I could do both by selecting which input (10VAC or 105VAC) to send to each intercom contact.

I don't understand the "A to K and K to A remove the condenser", so maybe that's why I don't get it yet.

Also, the ring generator is not currently in use since I'm not using common audible on the 551C yet. My CO lines ring bells directly in a couple sets. I would think that if I did hook up the ring generator to the CA, I could also send it to the audible input on the Tone Commander as well.

You are also right that at some point I will also hook up a couple intercom contacts to garage doors, so keeping the 10VAC on the Tone Commander likely gives me the most options for non-phone signaling (with an external relay).

Thanks, -Stryder

An external rotary or tone (RT) intercom unit mfg by Tone Commander, provides signaling to 19 stations. The RT3600 is the big brother for 36 intercom stations. I think (guess) the 00 (hundred) on the end of RT1900 is just marketing hype. RT-1900 sounds more powerful than Melco's RC-19 ;-)

-Stryder

Stryder:

Station Specialties is expressing the fact that there a zillion things that can be done with 1A2 equipment and he is right. It's just not a simple programming issue, nor just a phone system, but it requires that you roll up your shirt sleeves and do a lot more thinking than programming today's more modern systems.

There's not much that you can't do with 1A2, but it's not always easy. You have to be forward-thinking and plan your project around "what-if's" or "if-then" situations. It can be done, but you have to possess a lot of patience unless you have worked with it for years. No single book or Website teaches this system; you learn from the school of hard knocks.

You would need to start up a diode matrix to share intercom and common ringing. You probably don't want to get into that, but if you do, it can be done.

There's only one intercom unit that I can remember that offered two different voltage inputs to permit ringing and buzzers. Valcom made it, but I am not sure if they even make them anymore.

Condenser is another term for capacitor. There is one connected between terminals A and K on the network for ringer isolation. It really only needs to be bypassed if you decide to mess with a diode matrix in the future.

It appears that you have a good grasp of your situation, so for now it's great that you have something to work with. As always, feel free to check back when you are ready to move further into this.

viking and wheellock both used to make ringing adapters. viking has one using a contact closure. just add a 10v relay. or take a piezo , if loud enough, and add a diode bridge

or use a relay to turn a radio on and off.. Remember LOUD Klaxon horns?

Yes of course we had a Klaxon in the fire station on the single line phone (emergency RED Line). That one must have been connected to the tip/ring from the CO since we did not have a key system (KSU) at the fire station. (Acutally the fire stations preferred to have a bank of single line phones with neon ring lamps, no KSU to deal with if the power was out).

Speaking of the fire station (this was in the the 1970's), they had this wacky signaling system on the RED line for the fire alarm. The RED phones had an exclusion key in the hook. With the phone off hook, you pull up the exclusion key, and push this external button (which sent tip to ground). This would close several can relays also connected to the line in parallel (thoughout the town where the alarm sirens were located). Sending tip to ground would cause the CO to ring the line and close the can relays to set off the fire alarm. The only catch was that only one RED phone could be off hook or else the line would not ring.

The part I never figured out was what kept the can relays from closing when the RED line would ring normally for an incoming call? I'm guessing the can relays were connected ring to ground?

One diode in line (1/2 wave) or a (4-diode) full wave bridge?