This circuit uses a dual op-amp IC LM358 and two transistors. It can be powered by a 6V maintenance-free rechargeable battery or a lead-acid...

This logic high/low indicator circuit comprises two ICs. One is hex inverter IC 7404 (IC1) and the other is a bistable multivibrator built around...

This low-cost short-wave transmitter is tunable from 10 to 15 MHz with the help of ½ Jgang condenser VC1, which determines the carrier frequency...

A bipolar junction transistor (BJT) has three regions, of which the emitter and the collector are made of the same type of semiconductor (‘n’...

Christmas just would not be Christmas if you do not put a flashing star on your Christmas tree. Here is the circuit of such...

You can take this white LED based night lamp on your picnic outings. The lamp has sound trigger and push-to-on facilities and gives ample...

If your car has an FM radio with stereo output but no inbuilt cassette player, this circuit will come handy for listening to your...

Here’s a low-cost DC to DC converter circuit that converts 6V DC into 12V DC. It uses no transformer and is easy to construct...

FM transmissions can be received within a range of 40 km. If you are in fringe areas, you may get a very weak signal....

Here is a simple non-contact AC power monitor for home appliances and laboratory equipment that should remain continuously switched-on. A fusefailure or power breakdown...