USB Powered, Stereo Computer Speaker

This is the circuit diagram of USB powered stereo computer speaker, or it widely known as multimedia speakers for PCs. The circuit has single-chipbased design, low-voltage electrical power supply, compatibility with USB power from computer, simple heat-sinking, inexpensive, large flexibility and wide temperature tolerance. At the heart of the circuit is IC TDA2822M. This IC… Read More »

Portable 230V Lamp Flasher

This is a portable, 230V high-power incandescent electric lamp flasher circuit diagram. It is actually basically a double flasher (alternating blinker) which could manage two different 230V AC loads (bulb lamps L1 and L2). The circuit is completely transistorised and battery-powered. The free-running oscillator circuit is realised working with two low-power, low-noise transistors T1 and… Read More »

4-Output Stage (5V/6V/9V/12V) Stabilized DC Power Supply

This is definitely an effective 4-output stage stabilized DC power supply unit for testing electronic circuits. It delivers very well regulated and stabilised output, that is important for most electronic circuits to provide good results. The circuit gives you an audio-visual indication if there is a short circuit in the PCB under test, so the… Read More »

Car Cigar Lighter to USB Power Socket

Here is the schematic design of car cigar lighter to USB power port. Nowadays, almost all computer systems have logic blocks for working with a USB port. In practice, a USB port is capable of supplying more than 100 mA of continuous electric current at 5V to the peripherals which are hooked up with the… Read More »

65W Power Amplifier using HEXFET

This is a high quality 65W power amplifier circuit based HEXFET IRF9540 and IRF540. The circuit is quite simple for amplifier with good sound quality. The component parts is easy to find at electronic store around your place. It uses split power supply. Q8, Q10, Q11, Q12, Q13 should be mounted on heatsink for thermic… Read More »

5V Regulated Power Supply with OverVoltage Protection

This is the circuit diagram of 5V Regulated Power Supply circuit, featured with over voltage protection. The circuit is based regulator chip 7805; Thyristor SCR 2N1595 and Dioda Zener 1N3997 for overvoltage protection circuit. The 5V regulated power supply is apply 74LS series integrated circuits which has to be really precise and tolerant of voltage… Read More »

1.3W RF Amplifier

This diagram is a schematic diagram of RF amplifier circuit. The circuit will amplify the RF signal about 10 times, 100mW input power to 1.3W output power. It use a general NPN RF transistor 2SC1970. You may apply other transistors, for example 2N442. Circuit Diagram: Circuit Works: RF system and specially in RF amplifiers, this… Read More »