Showing posts with label bell. Show all posts
Showing posts with label bell. Show all posts
Saturday, July 6, 2013
Build Door Bell Timer with Adjustable Timing Facility
Yes this simple transistor circuit can be used as a home door bell and it’s ON time can be set as preferred by the user, meaning if you wanted that the sound of the bell to remain switched ON for a particular period of time, you could easily do it just by adjusting the given pot.
The actual tune is derived from the IC UM66 and the associated components, while all the included transistors along with the relay are configured for producing the time delay for keeping the music switched ON. Link
Parts List
R1, R2, R4, R5 = 1K
VR1 = 100K,
D1, D2 = 1N4007,
C1, C2 = 100uF/25
T1, T3 = BC547,
T1, T3 = BC547,
T2 = BC557
Z1 = 3V/400mW
Transformer = 0-12V/500mA,
S1 = Bell Push
IC = UM66
Tuesday, April 2, 2013
Ding Dong Door Bell Circuit Design using 8021 2 IC
The following schematic shows a Ding Dong Door Bell Circuit Design using 8021-2 IC. The 8021-2 IC is an 8-pin DIP having an in-built circuitry to produce dingdong sound each time its pin 3 is pulled low. The Ding Dong Door Bell Circuit Design consists of: On-Off Switch, 3Volt Battery, push to on switch, speaker, transistors and resistor.
Subscribe to:
Posts (Atom)