Mains Current Indicator with a LED
This is a mains 230V AC load current indicator and is a LIVE CIRCUIT, so take care. The Resistors have to be a fusible ceramic wire wound. People learning Electricity and Magnetism or Hobby...
Category: Discrete-Circuits
Telephone status indicator with LED
This will monitor telephone status without loading the telephone line, this way if you have two phones in parallel you will know if one of them is busy. Connect the two ends of circuit...
Flashing Mains Neon Lamp
Here is a Neon Flasher circuit (untested) for a user request at Circuits FAQ. This can be built into a switchboard or a gadget for indicating Live Power. D1-C1 form a simple half-wave rectifier,...
Ohmmeter – Simple Resistance Measurement
Measurement of resistor values in circuit configurations are required to be made often, as these might have changed in value due to various tolerance ranges, and hence could be the cause of faults. Likewise...
