Showing posts with label Bell Rumah. Show all posts
Showing posts with label Bell Rumah. Show all posts

Thursday, 22 March 2012

Touch Switch Door Bell Type

Skema Rangkaian Bel Pintu Saklar Sentuh

Wednesday, 21 March 2012

Rangkaian Bel Ding dong

Ding dong bel Rumah
Skema Rangkaian bel Rumah
This simple circuit an low cost ding dong bell suitable for calling bell purposes. It is made around IC 8021-2 . IC 8021 has an in-built circuitry to produce ding dong sound each time its pin 3 is pulled low. The sound is stored in a 4 bit ROM.a complementary-pair, two-transistor amplifier is used to amplify the sound to a fair level of audibility. A piezo tweeter or an 8-ohm, 500mW speaker can be used at the output.