Two-tone doorbell circuit

Posted on Feb 5, 2014

Use the 48V (60V) DC feedback electric current which is provided by the phone feedback line as the working energy of the electronic doorbell is very economical and practical. Now I introduce one kind of two-tone doorbell circuit with out battery. The circuit is as shown, circuit in this figure is the variant of conventional telephone ringing circuit. a, b..

Two-tone doorbell circuit
Click here to download the full size of the above Circuit.

Leave Comment

characters left:

New Circuits



Popular Circuits

40 meters CW Transceiver
Urban Sensing Networks using Arduino
Wireless Electronics for Communication
Dual power supply using L165
motor controller
Third harmonic excitation device automatic circuit a thyristor