At 04:21 PM 12/17/97 EST5EDT, you wrote:
>Does anybody out there know if it is possible to "shunt" the ring
>from a "home" telephone system.  What I mean by that is is it
>possible to stop all extensions on the system from ringing from a
>single extension?
>
>Mabye by apllying an alternating current to "even out" the ring wave,
>or shunting the ring wire to ground or something like that?
>
>Thanks,
>
>Shawn Ellis
>sellis@rx.uga.edu
>

If you are talking about regular phone service (POTS) in the US, I think
that simple shorting the line at any extension would diable ringing and all
phone service throughout the house. If you want to disable just the ring,
it might still be possible, depending on how the house is wired, to put
some type of zener or TVS device on one of the extensions and short just
the ring signal, and this might work throughout the entire house. In the
US's regular phone system, there is no separate ring signal line, the ring
is simply transmitted as an approx. 90V ac signal on the same twisted pair
as the voice is transmitted. The line is normall at about 40V dc and a
phone presents something like 500 ohms resistance when off the hook.

Sean


+--------------------------------+
| Sean Breheny                   |
| Amateur Radio Callsign: KA3YXM |
| Electrical Engineering Student |
+--------------------------------+
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