KS-16751.L1 Tester

[Babybearjs]

I came across this on Ebay and was wondering what it was used for? I've seen this item on Ebay before, but never gave it much thought... I'd like to know what BSP covered this tool... I'd like to read up on it to learn more about its application and purpose....

     http://www.ebay.com/itm/vintage-telephone-line-relay-indicator-KS-16751-L1-BELL-SYSTEM-WESTERN-ELECTRIC-/162533040413

[Alex G. Bell]

I came across this on Ebay and was wondering what it was used for? I've seen this item on Ebay before, but never gave it much thought... I'd like to know what BSP covered this tool... I'd like to read up on it to learn more about its application and purpose....

     http://www.ebay.com/itm/vintage-telephone-line-relay-indicator-KS-16751-L1-BELL-SYSTEM-WESTERN-ELECTRIC-/162533040413

No. 5 Crossbar offices and crossbar PABXs stored customer dialed digits and other temporary information in reed relay units containing 5 elements with numeric values coded 0-1-2-4-7 using 2-out-of-5 code.  The reed packs had a terminal on the front for each reed element for displaying the state of each element.  This device was used to display those states during troubleshooting by pressing it onto the 5 terminals and connecting the lead to the -48V supply.

There are BSPs in the 074 tool division identifying its application and probably in the 218 No. 5 crossbar division describing how to use it.

[Babybearjs]

so it was a CO tool. did they have anything like that for testing 1A1 and 1A2 systems?

[Alex G. Bell]

so it was a CO tool. did they have anything like that for testing 1A1 and 1A2 systems?

Can't think of any comparable tool in 1A2 nor any comparable situation where there were codes to read out.  CO guys also had test lamps:  a probe with a built in lamp for determining the state of a single circuit node in relay equipment but I never saw a KTS guy who had one.

[Victor Laszlo]

KTS and PBX repairmen made our own test lamps from parts found around the shop.

One was a combination of a station jack and a station lamp from a manual 55x series switchboard. It was used to check battery, ground, and generator on switchboard cords.

To check 400-type line cards in 1A2 KTS, we made a small box that had two momentary buttons (one for T/R, one for A1/A) and a 51-A lamp. It was used at the KTS MDF to check proper operation of the HOLD operation.

[Babybearjs]

Vic, thanks for the info.... it looks like I'm going to have to makeup my own unit too...

[Victor Laszlo]

There are adapters available that allow a Merlin cord to be connected directly to 8 consecutive pins on a 66-type block.  By creating the 1A2 tester wired to a 4 conductor cord, the procedure would be quicker. Just plug-n-test. When I made my first tester, the Merlin family of products was just a gleam in Ma Bell's eye.

[Alex G. Bell]

There are adapters available that allow a Merlin cord to be connected directly to 8 consecutive pins on a 66-type block.  By creating the 1A2 tester wired to a 4 conductor cord, the procedure would be quicker. Just plug-n-test. When I made my first tester, the Merlin family of products was just a gleam in Ma Bell's eye.

Actually, Siemon makes 66-to-modular adapters for 2, 4, 6 and 8 contacts.  The jack ends of the 2s are of course wider than 2 contacts on the block so they cannot be placed on consecutive pairs but the wider ones can.