This is 2 x 3W stereo audio amplifier based on IC power BA5406. This circuit which will give you 3W power in each channel. This circuit will be great for indoor audio system. Components List: R1, R2 = 120 ohm R3, R4 = 2R2 ohm C1, C2, C11, C12 = 220nF nonpolar capacitor C3, C4,… Read More »
This is 2x1W stereo amplifier circuit based on single IC KA2209. IC KA2209 is an equivalent IC to the TDA2822, you can use TDA2822 if you can’t find KA2209. It is ideal for battery powered operation since the supply required for this circuit is 2V to 9VDC. Power output depends critically on speaker resistance &… Read More »
This is 1W stereo audio amplifier with LM386N. The output power is 1 watt for each channel, so it should be use two ICs of LM386N National Semiconductor for stereo channel. This circuit belongs to kitsrus.com and the kit is available there or at electronickits.com. This circuit only need 10mA current with best voltage supply… Read More »
This is the circuit diagram of 1W audio amplifier which use TDA7052 as the main component and other 5 pieces of components to support the main component. The ideal supply voltage of this circuit is about 6-12V and no heatsink required. The schematic is for mono audio channel, just build two similar circuit for stereo… Read More »
Flame, gas and smoke detector for fire alarm. You can combine this circuit with alarm circuit. The output will be the relay which switch on and switch off the alarm. Schematic diagram:
The following circuit is a simple fire alarm circuit based NE555 timer and use thermistor as a temperature detector. This sensor will activate the transistor when the temperature is in high value. The thermistor will have a low resistance at high temperature, while at low temperature, the transistor resistance is high. This characteristic of thermitor… Read More »
Here is the circuit diagram of simple multitone alarm. This is a low cost circuit which is simple and easy to build. The main components of this circuit is based on dual op-amp MC1458 and LM 380. The two op amps inside the MC 1458 are used to produce square and triangular waves. LM 380… Read More »
This document is the manual of 2x90W Stereo Tube Power Amplifier with EL34, model K4040 by Velleman. The document in PDF version contain of schematic diagram, part list, component guide, step by step how to build the circuit. This circuit is for advance hobbysts… 🙂
Here is the circuit diagram of active DC voltage doubler which used to increase the DC voltage. This circuit drives relays of 24 and 18VDC from a 12V power supply. Use this circuit can be work with almost any PNP or NPN power transistor, of course the transistor with specific characteristic similar to the transistor… Read More »