atcomsystems.ca/forum Forums Other TDM Phone Systems 1A2 and Comkey Telephones & Systems "228A" KTU?

Hi,

I found on e-pay, something listed as a '228A' KTU. It looks more like a screw terminal board with some kind of connectors on the other side.

Was this part of a larger system? Just curious.

Thanks in advance!

Joe

Joe, you are correct. This is nothing but a screw terminal strip with wire wrap pins on the back side. I don't know exactly what it would have been used for except to perhaps fabricate a diode matrix or some other field assembly. I've never seen that KTU before. Most of the 2xx KTUs were used in 1A1, 1A2 and 6A systems.

Me either, Ed. I'm with you - It's got to be a device for "neatly" terminating components you needed to add to a larger (1A1 or 6A system).

My guess is that you would remove the front screw panel, wire up whatever components (diodes, capacitors, etc.) you needed for a circuit to the wire wrap terminals on the back, tuck them all in neatly, replace the front panel and then make your wiring connections to the system on the front screw terminals.

The components are now hidden away behind the plate, making for a nice, clean "Bell System approved" install.

Sam

I have a picture of the back of an old DSI (Intercom) and looks like the same 228A where all the signal leads and lamps were tied down.

Exactly what I was thinking. Perhaps an early type of diode matrix before someone figured out how to make them with a 66B3 block.

Per BSP 518-114-110 Issue 3, October 1972:

"228A KTU (Blank Unit)

"The 228A KTU is a blank unit with 40 screw type terminals. It is used for miscellaneous purposes."

Here in socal we had several in a 3A acd, used for traffic studys. The various registers were wired to the wire wrap and the front screws were wired to 25- 50 pr cables to a peg count box for the traffic study.

Good catch, Arthur! I looked through my BSPs and couldn't find it listed.


QUOTE]Originally posted by Arthur P. Bloom:
Per BSP 518-114-110 Issue 3, October 1972:

"228A KTU (Blank Unit)

"The 228A KTU is a blank unit with 40 screw type terminals. It is used for miscellaneous purposes." [/QUOTE]


Well, there's a BSP for you! Straight, succinct and to the point! :rofl:

Now I know just what to use it for. :bang:


Sam

Before the 66-type terminals were introduced, and during the "assemble it yourself" era of K-plans, there were often situations where groups of multiple leads needed to be terminated within a KSU. The 228A provided the facilities to do so.