phone cct

[grod]

Can anyone explain how I can make a telephone ring without being connected
to the telephone line. This is for a play.

Thanks

 

[jakdedert]

Much easier to download (or record) a sample of a phone ringing and play it
at the appropriate time in the script. If you insist on having the actual
phone ring, there are a few ways to do it. Technically, you need to apply
around 90 volts ac to the two wires on the input at somewhere between 15 and
30 Hz.

A google search on "telephone" would pull up a number of resources, or try
here: http://telephonetribute.com/technical_information.htm

jak

"grod" <grodgers@videotron.ca> wrote in message
newsnEBb.37281$YJ6.535911@wagner.videotron.net...

Can anyone explain how I can make a telephone ring without being connected
to the telephone line. This is for a play.

Thanks

 

[Dr. Anton Squeegee]

In article <PnEBb.37281$YJ6.535911@wagner.videotron.net>,
grodgers@videotron.ca says...

Can anyone explain how I can make a telephone ring without being connected
to the telephone line. This is for a play.

No problem. While the phone is on-hook, you would need to apply an
AC voltage of 80-120V at 20-30Hz.

This voltage can be generated in a number of ways: A variable
amplitude/frequency AC source, such as those made by California
Instruments (the 'Invertron' series) and others; The ring voltage
generators made by Tellabs (available from most branches of Graybar
Electric, probably run you about $50-$70 or so), or one of the old 1A2
key system power supplies that have a ring frequency generator built in.
These turn up on Ebay every so often.

DO NOT, under ANY conditions, try to use a generic AC line
connection. It's the wrong frequency, and not current-limited.


--
Dr. Anton Squeegee, Director, Dutch Surrealist Plumbing Institute
(Known to some as Bruce Lane, KC7GR)
kyrrin a/t bluefeathertech d-o=t c&o&m
Motorola Radio Programming & Service Available -
http://www.bluefeathertech.com/rf.html
"Quando Omni Flunkus Moritati" (Red Green)

 

[Jerry Greenberg]

You need a source of 96 Volts at 25 Hz. It would be cheaper and
easier to install a phone line, or run an extension from one to do
this. You then can dial the phone to ring it.

Or, have a recording of a phone ringing, and play it through a speaker
that is under the phone.

Jerry Greenberg
http://www.zoom-one.com

--


"grod" <grodgers@videotron.ca> wrote in message news:<PnEBb.37281$YJ6.535911@wagner.videotron.net>...

Can anyone explain how I can make a telephone ring without being connected
to the telephone line. This is for a play.

Thanks

 

[Tim Mitchell]

In article <460a833b.0312101418.5afc7ccf@posting.google.com>, Jerry
Greenberg <jerryg50@hotmail.com> writes

You need a source of 96 Volts at 25 Hz. It would be cheaper and
easier to install a phone line, or run an extension from one to do
this. You then can dial the phone to ring it.

OOOO, no you don't want to do that for a play. You can just rely on

someone ringing it accidentally (or on purpose) at an unexpected moment.

If you look in the google archive for rec.arts.theatre.stagecraft for
"phone ringer" you will find lots of pointers for this including some
circuits.
--
Tim Mitchell