In this article I have explained a simple walkie talkie circuit that can be easily built by any hobbyist and used for communicating between rooms or floors or simply for having some fun across neighbors and friends. The range of this system is around 30 meters. A walkie-talkie, also commonly referred to as handheld transceiver is […]
Simple
5 Simple Motion Detector Circuits using PIR
A PIR motion sensor alarm is a device which detects the infrared radiation from a moving human body and triggers an an audible alarm. In this post I have explained 5 simple motion detector circuits using op amp and transistor. We also discuss the pinout details of the standard passive infrared (PIR) sensor RE200B. We […]
Simple Mobile Phone Detector Circuit [Tested]
A cellphone or mobile phone detector is actually a high gain op amp amplifier which detects slightest of RF disturbance from a mobile phone, and illuminates an LED. Mobile phones today being the major generator of RF interference is easily picked up by this circuit and can be seen through an LED illumination at the […]
Simple TV Transmitter Circuit (Audio and Video Combined)
The TV transmitter circuit presented in this post incorporates the European standard FM frequency for audio and Video up-links. Referring to the circuit below, Q1 is configured as a preamplifier for amplifying the audio input to be modulated. Circuit Description Q2 is fundamentally responsible for conducting a couple of important functions: It amplifies the carrier frequency […]
Simple Digital Clock using LM8650 IC Circuit
The digital time clock explained here is a circuit which most electronic amateurs would love to make. You might have heard about digital clocks made from clock ICs such as the popular LM8361, MM5387 etc but these ICs could be today quite obsolete and/or complex to build. Circuit Operation The present design is much easier […]
9 Simple Sine Wave Generator Circuits Explored
A sine wave generator is actually a sine wave oscillator circuit which generates an exponentially rising and falling sinusoidal waveform. The 9 simple sine wave generator circuits presented in the following article are easy to build, since they incorporate a small number of ordinary electronic components, and can be used for generating an exponentially varying […]