Re: telephone ringer voltage

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Article #16544

#16544

From: Michael T Ford
Date: Thu, 07 Jan 1993 11:31

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In article <jecome01.726341429@starbase.spd.louisville.edu> jecome01@vulcan.spd.louisville.edu (Eric Comer) writes:
>I was wondering if anyone knew the voltage that is sent on the ringer
>line of a telephone cable when a call is incoming.  any help would be
>greatly appreciated.

The normal onhook voltage in the US is -48V.  When the phone rings
it is caused by a modulation of approximately 90-100 V at about 
20 (if I remember correctly) Hz.

73, 
Mike WZ0C

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From: cthomas@athena.mit.edu (Michael T Ford)
Subject: Re: telephone ringer voltage
Message-ID: <1993Jan7.113112.15048@athena.mit.edu>
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Date: Thu, 7 Jan 1993 11:31:12 GMT
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