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 […]
Newly Updated Circuit Projects:
Wireless Mobile Phone Charger Circuit
A wireless mobile phone battery charger is a device that charges a compatible cellphone or mobile phone placed close to it, through high frequency wireless current transfer, without any physical contact. In this post I have explained how to build a wireless cellphone battery charger circuit for facilitating a cordless cellphone charging without employing a […]
How to Design Your Own Inverter Transformer
Designing an inverter transformer can be a complex affair. However, using the various formulas and by taking the help of one practical example shown here, the operations involved finally become very easy. The present article explains through a practical example the process of applying the various formulas for making an inverter transformer.The various formulas required […]
How to Convert an Inverter to an UPS
An inverter is an equipment which will convert a battery voltage or any DC (normally a high current) into a higher mains equivalent voltage (120V, or 220V), however unlike an UPS inverters may lack one feature, that is these may not be able to switch from mains battery charging mode to inverter mode and vice […]
Very Simple BLDC Motor Driver Circuits using Back EMF
In this post we investigate what’s a BLDC motor and subsequently I have explained regarding the design of a sensorless BLDC motor driver circuit. BLDC CPU Fans Seen those fast moving fans in CPUs, voltage stabilizers, DVD players, and other similar equipment, which work with utmost efficiency, consuming minimum space, current and yet are able […]
Simplest 100 Watt LED Bulb Circuit
In this article I have explained a very simple 100 watt LED bulb circuit using a few high voltage capacitors. The entire circuit could be built at a cost less than $25. I have already discussed many capacitive type of transformerless power supply circuits in this blog, however all these suffers from a couple of […]





