Low Noise audio amplifier.



Yes, it somewhat looks a spider with 6 legs (:P) and I believe it scares the real spiders and even bugs LOL.

spider pic 003


Audio Exciter:

Exciter is also known as bodyshaker, Audio Exciter is  just basically a loud speaker without a membrane, and it consists of voice  coil , oscillating mass and mounting ring/plate.  If the audio/music signal is applied to the contact pins of the voice coil, the oscillating mass starts shaking with the frequency of the applied music more


LED candle avr

LM4752 amplifier

LM4752 is a stereo audio amplifier capable of delivering 11watt per channel of continuous average output power to a 4Ω load

lm4752s amp pic2



KA7500c application circuit


This buck converter/step down  is based on KA7500c SMPS controller chip,


LM4755 audio amplifier


I built this amplifier for my iPod,  amp circuit based on LM4755 chip more


AM Transmitter


I am always interested in building radio circuits.

I used copper clad boards and really like the construction, not neat though, I do remember that I sprayed thicker coats of lacquer on the board before laying the parts on it. read more


TDA2822M (bridge amp)

 PIC2_2822mThis is a part of my RF transceiver project, no parts for building tranceiver yet ,  so i have started with the audio amp circuit,  amplifier circuit is based on TDA2822M chip which is  configured in bridge mode and I used a single sided Copper plated board for Manhattan construction. read more

Wireless power transmitter and receiver 

CoilsWorking model of wireless power transmitter and receiver.  The Transmitter and Receiver coils with capacitors connected to each coils, forms a tank circuits that resonates with a frequency of f = 1/(2π√(LC)), if the two resonant circuits resonating at the same frequency and were brought to close, the energy  read more


LDR Light Switch

WP_20160129_006LDR (light dependent resistor) is a passive optical transducer, the resistance of LDR decreases with increase in light intensity, LDR or photoresistor is applied in light sensing detecting circuits, light or dark activated switches.  The resistance of LDR is in the order of few MΩ in the dark and few read more


BD139 BD140 Audio Amplifier

WP_20151214_019This is the small audio amplifier circuit, with decent power output of 3watts RMS into 4ohms load. so not a boom sound. R4,R5 resistors forms voltage divider and biases the transistor Q1. the voltage across the R4 is (Vin*R4)/(R4+R5) 3.75Volts , if you increase the resistance the more the voltage read more

IR Sensor Module

Sensor Module

IR emitter:

It is a LED emits infrared light (940nm typically) applications of IR LED: like optical counters, free air data transmission, infrared remote control, card readers , etc…. read more