[BC] Origin of acronym QKT

[Mark Durenberger]

Thought you might enjoy the mini-thread (below) re-arranged in order.  Dave 
Hultsman began it...

Mark Durenberger


Dave said:  I believe that the "QKT"  is the USOC designation for the Bell 
Labs Spec'd 30-A Coupler.  Two and three letter USOC codes were used for 
specifying billing on equipment to phone customers.  I have forgotten what 
USOC is?  Some phone person can probably tell  us. United States Operating 
Companies?


From: Mark Durenberger:


It may be an arbitrary appellation...part of the USOC (Universal Service 
Order Code) used by most of the BOCs.

 http://bellsmind.net/USOC/USOCS-Q.html
 http://www.sbc.com/Large-Files/RIMS/Wisconsin/Tariff_No._20/wi202002.pdf


From: "Mike Schillhahn"
Hi!  Was lurking on the list, and my memory from the Bell System install 
manual that one of the local guys left on my desk one day in the early 70's 
is that QKT stood for "Quick Connect" to CPE. The circuit included a diode 
that limited it to the maximum -9 feed level - above that, it clipped. I've 
been looking for the manual, but it seems to have disappeared...


>From Mark Durenberger:

Hi Mike.  I have one in my junk box :-))  There's a tiny transformer and a 
DC blocking capacitor.  IIRC, you switched in the QKT by pulling up on one 
of the two white plastic hook-switch pins on the phone.
Regards,


From: "Mike Schillhahn" <mike at schillhahngroup.com>

The white key was called the "exclusion" key, if I remember correctly (you 
could order it permanently connected to the hybrid), and there was a handset 
mute switch that could be ordered either in the handset (push to talk) or as 
a turn switch down on the lower right hand site of the instrument.  Both 
simply shorted the mouthpiece.

What I liked about (the QKTs) was that they were bi-directional -- we could 
use them to extract audio as easily as feeding something into the line.  I 
had them installed on all the newsroom and studio phones -- it made it easy 
to grab interviews anyplace, and a breeze to set up an ad hoc network feed.


>From Durenberger:

Remember the cool handset switch you could wire backwards?  I did this in 
response to newsfolks wanting to be able to cradle the handset on their 
shoulder, carrying on a conversation while typing with both hands.  Instead 
of "squeeze-to-talk" you would "squeeze-to-cut-off" the local mouthpiece, 
for a clean recording.

Anyone else...?

Mark Durenberger