Subject: | Re: How do you make a LandLine Telephone Ring?
| Date: | Thu, 10 Jul 2003 17:01:23 +0100
| From: | "Owain" <owain001@stirlingcity.co.uk>
| Newsgroups: | uk.telecom
|
"DeeInLondon" wrote
| If I want to test a telephone's ringer - and there's no working phoneline
to
| plug it into and call the phone - how do I do it?
| Do I apply a voltage across a certain part of the connection points?
| Is anyone know please do enlighten me.. Do I need specialist equipment or
| can I build a simply circuit to do the job?
The ringing voltage is normally 40-100 V a.c., and lower in freqency than
mains, say 17 to 25Hz.
However most phones (especially if there is only one of them, and you're not
working over several miles of cable) will ring with much less voltage and
won't worry about the frequency.
Get a Master socket (one with a ringing capacitor in) from eg Maplin and
something like a mains to 24V transformer, apply the 24Vac to pins 2 and 5
of the socket, and the phone should ring. (Usual disclaimers apply.)
Alternatively if you find a linesman's phone on ebay most of these have
either a magneto generator (hand crank) or electronics to generate the
ringing voltage, also talk battery, enabling them to be used as an intercom
to a normal phone.
Owain
|