Electronic Calling Bell Circuit Diagram. Electronic doorbell light this 6v battery operated doorbell light circuit can be connected in parallel with any existing ac230v doorbell. When anyone push the doorbell switch the bell sounds as usual and ac mains supply available across the doorbell is routed to the input of this circuit through an opto coupler ic1.
Electronic doorbell light this 6v battery operated doorbell light circuit can be connected in parallel with any existing ac230v doorbell. The main objective of the doorbell circuit is to convert electrical signals input into audio signals output with a single press of a switch. The ic has an in built circuitry to produce ding dong sound each time its pin 3 is pulled low.
The transmitter circuit is built around 5v voltage regulator 7805 ic1 encoder ht12e ic2 a dip switch dip1 and a few other components.
Circuit diagram of transmitter unit for the wireless doorbell. Ic2 converts 12 bit 8 bit address and 4 bit data parallel data to serial data which is available at its dout pin. The bc547 transistor along with the associated preset and the 100uf capacitor form a simple delay off timer circuit where the preset and the capacitor determines the delay for which the sound output may be sustained once the indicated push button is pressed momentarily. The main part of this doorbell circuit are two ne555 timer ics when some one presses switch s1 momentarily the loud speaker sounds a bell tone as long as the time period of the monostable multivibrator built around ic1.
