atcomsystems.ca/forum Forums Other TDM Phone Systems 1A2 and Comkey Telephones & Systems 1a2 system

ok. Thanks everyone. I am a little confused. I am looking at the ksu. On the 66 punchdown, there is an a and a b side. the 5 columns are bridged to half way down. Heres what i have:
A:
t
r
a
a1
lg
l
t
r
a
a1
lg
l

t
r
a
a1
lg
l

t
r
a
a1
lg
l

Then after that there are two unbridged rows

then on the a side (2 columns)
b1
r1
b1
r1
b1
r1
b1
r1
ca
ca
ca
ca
-
-
-
-
t
r
t
r
t
r
t
r
(BOTTOM)
Note- each of the "r1"s are connected by a piece of green wire to the respective order on the "ca"s. Hopefullly i havent lost you guys yet. Now, theres the other side (b). Starting from the bottom, since there is a huge gap where the labels are blank- i have
rb
rg
bb
bb
gb
gb
ba
ga
s+-
g+-
lb
lg
mb
mg

and lb and mb are connected with a piece of blue on yellow wire.

I have 2 empty line slots. The other two have 400D ktu cards that do work. So, I am hoping everyone can give me pointers on how to hook up the phones. I am not using the amphenol connectors- I am hardwiring everything. If it all works, then I will get fancy later. Thanks EV. I figured out the melco wiring, and I am begining to understand how this all works. Believe it or not- Years ago, I actually had this thing working- but I didnt fully understand it, and the features didnt really work and nothing would ring. Thanks a lot to everyone who is helping.

1st line tr white blue to set, A1 A control leads white orange to set, LG L lamp leads white green to set. Than your second line to the set right down per color code. The bottom tr are your CO feeds, line one on down. b1 r1 are your common bell leads. (mind you this is all from a faulty memory) rb rg I'm pretty sure is where the ring generator goes. The rest are battery and ground leads, ones filtered the other isn't, the filtered is your talk battery for intercom. I believe these leads will be connected to the power supply. As far as the 400D's go slot one will be line one, so the way you have it the first two lines would be dead. Hope this helps, I think it's mostly accurate and if not I'm sure someone else will chime in.

ok. Thanks a lot. Why are those jumpers from r1 to ca ? (there are several jumpers)

Ring leads for common audible.

The R1 and B1 leads are the ringing output from the line card. For convenience, they were strapped over to pairs of "CA" clips (the green wires you described) to provide "tip/ring" connection connection for the ringer. This way, you could punch the yellow-slate (station ringer) pair down and leave it alone. Line ringing options were then handled on the "CA" (common audible) clips with jumpers for the desired lines.

To have multiple lines ring on the same phone(s), a strap is simply "daisy-chained" among the desired CA clips. It was set up this way so that you had a point to punch down the outgoing pair and still have a separate point to tie line card's ringing outputs together.

Don't forget, in order for this to work, you will need a ringing generator input, connected to terminals RG and RC. These are the bottom two clips on the right side of the block. A 551C KSU had a bracket that allowed a 118A frequency (ringing voltage) generator to hang in front of the interruper. If you don't have this, you can always use another external ring generator.

There's also a way to arrange multiple lines to ring without a ring generator off of the CO line ringing, but some special strapping is required on the KSU's block. Since you have 400D line cards, that won't be a problem. If you want to go with that, let me know and I can give you the info. It's easy.

Ok. Thanks a lot. I do have the frequency/ringing generator. I will just connect the yellow slate pair to the ca. Thanks again.

I have had a lot of success with my home 1a2 setup. Thanks to help from a member of this board all the materials I needed came together. Some phones are hardwired, some are on Amphenols. Are you using CO lines as inputs, or using pbx lines? Being kind of color blind has made this a lot more work, but I am actually numbering the pairs before I install them, then punch down, and add cables to run to the phones. Have two CO lines, and 6 lines from a home pbx, which also acts as intercom. When ringing more than one line to prevent backfeeding to all ringers connected to the other lines a diode matrix may be needed. After learning the basics I was able to help a local guy set up his too. Haven't used the buzzers yet, since most of my phones don't have them

You can ruminate all you want on how you know everything about 1A2 home systems, but I worked on older stuff than that before you were out of diapers.

I have the original Cambell Soup tin cans that I modified to use with metalicized 10 lb. fishing wire and a 1/8 inch reel to reel tape recorder for voice mail. The rotary dial pad was so old it was in Roman numerals. I bet you can't even remember the polarity on that system.

<GRIN> Bunnie

For you 1a2 fans there are 2564 sets on E-BAY
plus the ever popular 6 button wall set with the handset on top.

To top off your search is a 20 button set ,looks like a speaker phone with a headset adapter

Good hunting on memory lane