22W Mobile Car Stereo Power Amplifier

The circuit diagram shows a powerful stereo amplifier which can deliver a power of 22W.It is built around popular single-chip audio power amplifier TDA1554Q (IC1).Here it is configured as two 22W stereo bridge amplifiers.

Listening to songs stored in mobile phone while driving is dangerous. It's also against laws. But you can use your mobile phone as a stereo music source and it requires amplification to drive speakers. Also This does away with the need of a sophisticated in-dash car music system.

Electronic Harmonium Using 555

Here's the circuit diagram of a simple electronic harmonium that can produce all the seven notes. As timer IC 555 based design, the circuit is very simple to assemble and use. It only requires single 555 IC, one or two capacitors and some resistors.

Simple UPS Circuit For Cordless Phones

This circuit diagram of UPS is designed to use with a cordless telephones that cannot be operated during power failure. Since the ups is only meant for telephone, it's output power is limiter to 1.5W. This ups circuit is economical and can be assembled on a general purpose PCB.

Simple Electronic Fan Regulator Circuit Using Triac

The circuit diagram provided is a triac - diac electronic fan regulator that would reduce your power usage of electric fans even in slow speeds. A normal resistor-inductor fan regulator heats up to waste eneegy  when the fan is running with lowers speeds or it controls motor speed via applying resistance between fan and power supply.

TDA2030 Subwoofer Amplifier Circuit

This TDA2030 amplifier circuit is ideal for driving low frequency subwoofer speakers in home theater systems.The TDA2030 is a monolithic integrated circuit intended for use as a low frequency class AB amplifier.