DIY SWR Meter






Extremely Low Frequency Reciever using Arduino


Using Arduino Uno and ADC module, this circuit can pick up ELF Signal

Car Radio Alarm Circuit


Car Lights Monitor


Brake Lights Alarm Monitor for Car


source : Elektor

Bicycle Lights and Alarm

source : Elektor electronic

Car Alarm



Source : Elektor Electronic

Car Fuse Monitor




Source : Elektor Electronic

Nicad Charger Circuit


Source : Elektor Electronic

Lead Acid Battery Charger




Source : Elektor Electronic

Metal Pipe Detector Circuit

This circuit is useful for trace Metal Pipe Water and Gas.

Metal Detector Circuit with 9 Volt battery


This circuit from 303 Circuit Elektor Electronics . The LC circuit frequency will change when the metal object altered the Inductance of inductor.

TUP, TUN, DUG, DUS

TUP is Transistor Universal PNP, TUN is Transistor Universal NPN, DUG is Diode Universal Germanium and DUS Diode Universal Silicon , are standard components that most retailers have in stock and have minimum specification that use as general purpose diode and low frequencies transistor with different type numbers and have similar specification.