Here in ZL the line voltage (nominally 50) is reversed behind the low freq
ringing as well- lotsa PBXs use the line reversal these days and not the
actual low freq ringing signal- makes for faster call answering. So in total
one has a total transverse voltage of 50 plus peak ringing to contend with-
in our case nominally 80 vac ringing gives a total of just over 160 volts.
Since the A leg is basically at or near dc ground potential thats as bad as
it gets-within a few volts- using locally ground referenced test gear.
73
Dave Brown, ZL3FJ
Christchurch
New Zealand
----- Original Message -----
From: John Andrews <[email protected]>
To: <[email protected]>
Sent: Friday, November 09, 2001 5:57 AM
Subject: Re: LF: Re: Ringing Voltage on Telephone , boo-boo
Larry,
I'm with John Davis on this one. The U.S. practice is 20 Hz for ringing --
nothing at 1 kHz.
John Andrews, W1TAG
> Larry, I have done. My statement was based on having checked it
personally
> on a number of Bell and non-Bell exchanges over the years. As I said,
it
may
> be different in Canada, but here it's 20Hz.
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