Indicator Circuit for Mains 220V Blown Fuse

This is indicator circuit to indicate that there is blown fuse, it will show the condition of fuse through LEDs. This circuit works for fuse 220V mains. This compact circuit is very useful and reliable. It is a low cost circuit which use very few components. Generally, when an electronic device indicates no power, the… Read More »

Electronic Quiz Button Table

This is the circuit diagram of electronic quiz button table. This circuit is simple, easy to built and of course it is not expensive. This quiz circuit used for four game participants. It determines the contestant who first presses the switch (S1 through S4) to answer a question and locks out the remaining three entries… Read More »

3V to 9V DC Converter

This is the circuit diagram of 3V to 9V DC converter which capable to deliver output voltage about 10.4v on no load and 9.6v @30mA. By using this circuit, You will be able to replace a 9v battery from 3V DC input.

2000W Class AB Power Amplifier

This is the circuit diagram of 2000W class AB power amplifier uses 7 pairs MJ15003 and MJ15004 transistors for the final amplification block. The circuit operated with 90V DC symmetrical (dual polarity) power supply circuit. The transistors must be mounted on heatsink to prevent the overheating, maintain the transistors work in maximum performance.

Power Amplifier 2000 Watt

This is linear power amplifier 2000 Watt which need advance knowledge in electronics since the schematic diagram is very complex for hand made circuit. I think you have to re-design the schematic diagram using circuit diagram software designer such as diptrace, eagle, expresspcb ect. Or just order the PCB online, they will be glad to… Read More »

Connection Tester

Here the low resistance connection tester which can be used as cable or wire tester, soldered joints and other types of connection with resistance value between 0.25 and 4 ohm. Circuit Notes: This simple circuit uses a 741 op-amp in differential mode as a continuity tester.

1.5W Audio Amplifier with IC SSM2211

This is 1.5W audio amplifier circuit design based on wide bandwidth, low distortion power IC SSM2211 from Analog Devices. This circuit is simple, inexpensive and easy to built with only contains few components. The SSM22111 is a high performance audio amplifier that delivers 1 W RMS of low distortion audio power into a bridge-connected 8… Read More »

Adjustable Regulated Battery Charger

This battery charger circuit is regulated and adjustable to make this circuit able to charge the mosto NiCAD battery. This adjustable regulated battery charger circuit will work for single cell or multi battery cell which connected with series/parallel connection. The maximum voltage of the batteries should be 18V maximum. Power transistors Q1 and Q2 are… Read More »

CD/DVD/Bluray-Disk Drives Troubleshooting and Repair Tutorial

This is the CD Drives troubleshooting and repair tutorial for your electronic service reference. It should be work and also largely relevant for DVD/HD DVD/Blu-ray equipment. This document was developed specifically for the troubleshooting and repair of the CD players in component stereo systems, compact stereos, boomboxes, car units and portables, as well as CDROM… Read More »