[SI-LIST] Re: -48v

Dear Santhosh,
A large voltage is required to generate a ringing tone in telephone
system.That's why it is recommended to have a 48 Volts.When phone rings it
gives atleast 40-45 Volts across the line.

Regards,
Mahesh Linge
----- Original Message -----
From: "Santhosh E P" <setavala@xxxxxxxxx>
To: <si-list@xxxxxxxxxxxxx>
Sent: Wednesday, March 24, 2004 11:17 AM
Subject: [SI-LIST] -48v


> hi all...
> is there any specific requirement of having -48v for telephone lines. if
> then whats the advantage? why we can't have other voltages to carry the
> signal, not even +ve?
> regards
> santhosh
>
>
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