Creating your Own Telephone Ne2 Rk: you can easily create
your own intercom system using two telephones, a 9-volt battery
(or some other simple power supply) and a300-ohm resistor
Remote Control using Telephone: Here is a tele-remote
circuit which enables switching "on" and "off" of appliances
through Telephone lines. The circuit described here can be used
to switch up to nine appliances (corresponding to the digits1
through 9 of DTMF the Telephone key-pad). The Telephone can be
used to switch on or switch off the appliances also while being
used for normal conversation. FAIR WARNING -- THIS SITE HAS
ANNOYING POP UP ADS.