atcomsystems.ca/forum Forums Other TDM Phone Systems 1A2 and Comkey Telephones & Systems 1A2 and some old WECO stuff

Hi Arthur,

I've PM-ed you.

Correct email address is [email protected]

Website is www.FireAcademyFoundation.org

Well, I got here to late to do much, except applaud.

Nice equipment. That Swiss unit looks spectacular.

As far as the equipment - it was probably either for a military base OR for the embassy. I had a friend who installed 1A2 in US Embassies overseas for many years. "Worked well, lasted long time" was the comment we used to make about it.

Sam

Great pictures! I notice on several of the 6 button sets, the 6th button is a "Mute" button. I've never read about this option in any BSP, although I always wished for this option! If there is a BSP, could you share the number, or if it's custom designed, can you post the wiring? thanks!!

I imagine that the A-A1 contacts on the 6th key are wired across the transmitter leads at the network. That would short out the transmitter and mute it.

Mute function is not realized yet. The idea is to install a toggle relay inside the telephone set and use this button to activate and deactivate the relay and mute option. I will keep you posted when the circuit is ready. I also want to utilize hold button lamp to indicate mute mode activated, but this is in wishlist yet. I will probably move the mute function out of pick up key of the telephone set to an external button block (four button blocks you see in matching colors to each rotary set, normally used for buzzer signaling). The other buttons are for 107A loudspeaker activation (want to realize on-hook dialing with each telephone set) and for central system switch from common audible based on ringers to buzzers ("quite" mode). I have quite some phones around the house and when all are ringing on incoming call it can be too loud, so I want to switch instantly from ringers to buzzers and back.
I'm currently busy with 551C KSU conversion to 230V and installing an electronic ringer generator (PowerDsine 12VDC to 70VAC rms @20Hz - works well with WE ringers) into shoebox power supply. Just received it from eBay and cleaned up for modification.
Also 584C panel is on its way to me - this is for back up and test 1A2 system. Will keep you updated.

One other way to get the MUTE feature installed, and be able to have it cancel automatically, is to use the contacts provided on the extra switch hook contacts along with the white "pull up" switch hook plunger. When it's pulled up, it mutes, and it automatically resets when the handset is hung up. There are enough contacts to activate the lamp under the HOLD button for that, too.

Getting the 107A to monitor the phone is possible. Getting the ability to dial while on-hook, without a lot of relays, will be difficult. The speakerphone units, both 3-type and 4-type, rely on extra switch hook contacts and control wires to accomplish that.

Yes, I want to install a relay inside the telephone set to make on-hook dialing similar to 4A speakerphone. There is enough space inside on the buzzer place (second gong of the bell). Problem could be to select relay with proper make before brake sequence to avoid false hold condition. I will have 18VAC to power relay anyway on spare pair of 50 pair cable (needed to power 106A loudspeakers).
I have unfortunately no exclusion kit on any of my sets.

My favorite KTU of all time was the 237B, which was originally designed for the add-on conference feature. It offered operation by using a non-locking line key to bridge two preset CO lines together. This non-locking key provided that 'toggle' functionality that you're seeking. The relay contacts on the KTU could be used for anything, not just conferencing lines. I used to use them for providing a one-touch 'night' button that would cause the 237B to activate a slave relay, placing a short on all of the CO lines in the system to force them to hunt (as busy), except the last one (Centrex), which had CFNA to a remote location.

It was also mighty handy for just a regular night bell throw switch that could be activated/deactivated by any station with that particular line key wired to it and unlocked. It offered plenty of separate contact closures so that T/R and lamp control could be accommodated for just about anything.

With that said, you could certainly use the 237B to toggle the mute function on and off using spare pairs in the line cord. To avoid imbalance hum, you'd need to use a full pair to and from the transmitter when placing the short across it. Otherwise, hum or bleed-through may occur if using split pairs (spares). Being a rack-mounted KTU, it obviously won't fit inside the set, however Mike Sandman offers some tiny relay concoctions that you can fit inside of a set.

HERE'S AN EXAMPLE OF ONE

To keep the installation as close to "BSP" as possible, you might want to know that in ComKey telephones that required power for the M-type relay in each set that was used for the privacy feature, -24Vdc was sent to each phone on the Brown/Violet lead of the mounting cord.