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From: wsrcc!wolfgang@uunet.uu.net (Wolfgang S. Rupprecht)
Newsgroups: comp.dcom.telecom
Subject: Re: For Telecom-ers Who Live up North
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Date: 7 Dec 90 17:02:50 GMT
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X-Telecom-Digest: Volume 10, Issue 872, Message 4 of 13


BRUCE@ccavax.camb.com (Barton F. Bruce) writes: 

>That is an OLD trick, but a slight modification may make sense.
>[...]  Instead of having the low temp thermostat simply short the
>line, have it connect a pair of back to back zeners across the line.
>68 volt ones normally work well when the CO battery is 48v. If you
>are on a DLL ckt with 72 or 96 volts, pick diodes a bit higher.
>Ringing superimposed on battery will trip when a zener fires, but the
>line will then go on hook instantly.

Ahem.  Old trick is right.  Didn't TAP recomend an NE-2 bulb?

Isn't this blatently illegal, just because is does interfere with call
progress detection in old exchanges?  I thought there were tight specs
on how fast you were allowed to go off-hook after the ring.


Wolfgang Rupprecht    wolfgang@wsrcc.com (or) uunet!wsrcc!wolfgang
Snail Mail Address:   Box 6524, Alexandria, VA 22306-0524