Bass Guitar Preamp Pedal

Here is the circuit diagram and PCB design for relatively low cost DIY bass guitar preamp pedal uses FET K117 or equivalent. There is a bit difficult to build this kind circuit project, it’s require a good knowledge in electronics. This preamp has several features for the bass guitar instrument such as attenuator, low cut, mid… Read More »

Small Sound Amplifier for Ears (Hearing Aid)

This is the simple project of small sound amplifier for ears or often called hearing aid device or hearing loss amplifier. This circuit was already tested on some patients and give significant improvement in the hearing ability to the patients. It consumes a very small amount of power within the range of 10 milliwatts. Furthermore,… Read More »

Galaxy Audio Booster using RC4558

The following is an electronic circuit called galaxy audio booster which serves to improve the performance of your audio system. This circuit uses an IC RC4558 in which there are two op-amp modules that can be used for stereo audio applications. The circuit is similar to stereo tone booster that uses the principle of High… 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 »

35W Power Audio Amplifier based LM391

Here the 35W power audio amplifier circuit based on LM391. Inductor L1 is constituted by 20 coils of wire, with thickness 0.9mm, round resistor R16. The transistors Q3-4 are the final amplification section, it should be placed on heatsink. If are used the Q3-4 in packing TIPxxxx they can be placed straight above in PCB.… Read More »