Mains Trigger Musical Door bell
Mains Trigger Musical Door bell
Various mains and battery operated doorbell project is already published in www.electronicsproject.org. Now, here is a unique project in the series of doorbell by Dreamlover technology, using both mains and battery. The doorbell published here used mains for only trigger and rest work in battery.
The circuit of mains trigger musical doorbell is fabricated around musical IC UM3482 followed by a transistor and a diode and some passive components. The ac mains supply is given to trigger pin 4 of IC1 through resistor R1 and R2 and diode D1. Resistor R4 is used to block unwanted trigger.
PARTS LIST
Resistors (all ¼-watt, ± 5% Carbon)
R1 = 220 KΩ
R2 = 33 KΩ
R3 = 22 KΩ
R4, R5 = 100 KΩ
Capacitors
C1 = 33 pF
Semiconductors
IC1 = UM3482 (Music IC)
T1 = BC147
D1 = 1N4007
Miscellaneous
SW1 = Push – To – On switch
LS1 = 8 Ω loudspeaker