Door Bell Circuit Using BEL 188 PCB

Posted on Feb 6, 2014

Circuit Here is a low cost one touch door bell circuit using Bel 188 transistor. I think this may be the most cheap bell circuit that can be made. The core of this circuit is a output transformer of push-pull amplifier that often used in transistor radios and a Bel 188 PNP transistor. The sound produced from the circuit of calling bell is a machin

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e gun like and it produces when ever we press the switch. It starts from loud and then fade out to silence. The circuit can be assembled on a common PCB. This door bell circuit is designed to work on a 9 Volt supply but it may works even low voltages at the cost of slightly reduced volume.

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