In this post I have explained the pinout assignments and functions of the popular 433 MHz RF remote control module from HOLTEK. RF 315 MHz / 433 MHz Transmitter-receiver Module for Remote Control Application Making your own universal remote control systems today is very easy. Such procure the relevant chips, assemble them and here goes, […]
Newly Updated Circuit Projects:
Simple Crowbar Circuits for Over-voltage Protection
A handful of simple DC over voltage protector crowbar circuits are discussed in this article. I have explained the working of each crowbar circuit through the following explanation. What is Crowbar Circuit If you are wondering what is a crowbar circuit, the definition is simple. It is a circuit network where a transistor or an […]
AC Millivolts Meter Circuit Using IC 741
In this article we study an op amp based millivolt meter circuit designed to measure AC millivolts accurately, I have explained the details from the following explanation. The circuit shown below can be used to measure DC potentials in the range of milli-volts. The circuit is highly sensitive and is calibrated to measure voltages in […]
How to Illuminate 100 LEDs from 6 Volt Battery
In this article I have explained an innovative way of driving more than a hundred white LEDs from a 6 volt battery. The circuit utilizes the IC 555 for driving a step up transformer, whose output is finally used for illuminating the LEDs. A special PWM configuration makes the circuit much power efficient. Main Stages […]
Making a Pyrometer Circuit
To make a furnace temperature meter, the sensing element is required to be particularly robust so that it is able to withstand the extreme high temperatures generally developed in furnaces and ovens. What is a Furnace The circuit of a pyrometer explained here is based on a thermocouple principle which can be used to read […]
FM Wireless Microphone Circuit – Construction Details
A wireless microphone is a portable electronic microphone which allows the user to transmit its voice to an amplifier without any wire connection, hence the name wireless microphone. Making a wireless mic at home can be real fun, here I have explained one such simple project which can be used for recording and paying back […]





