In this post I have explained a circuit which can be used for controlling 1 to 8 appliances with a single RF 433MHz remote control handset. Now you can control fans, lights ACs, oven etc within a range of 50 meters with the same remote. In a few of my earlier posts I have comprehensively […]
Archives for 2016
Opamp Hysteresis – Calculations and Design Considerations
In most automatic battery charger circuits in this blog you might have seen an opamp with a hysteresis feature included for some crucial function. In the following post I have explained the significance and design techniques for the hysteresis function in opamp circuits. To learn exactly what’s a hysteresis you can refer to this article […]
Bluetooth Car Ignition Lock Circuit – Keyless Car Protection
This circuit will allow the user to lock his car ignition using his phone Bluetooth, meaning the ignition can be locked/unlocked only through a specific code from the user’s cellphone Bluetooth. Overview In one of my earlier posts I have already explained how to hack a Bluetooth headset and use it for any desired switching […]
Arduino based Battery Over Discharge Protection Circuit
In this post, I will show how to construct a over discharge protection circuit for 12v battery using Arduino which can protect 12V SLA battery against over discharge, and also protect the connected load from over voltage in case of overcharged battery is connected. Understanding Battery Charge/Discharge Rates All the batteries have natural decline, […]
How PNP Transistors Work
In this post I have explained regarding how a PNP transistor works or conducts in response to a fixed biasing voltage and a varying supply voltage, across its base and emitter. The question was put forth by Mr. Aaron Keenan. Question Regarding PNP BJT Working Great information and lots of interesting circuits!I have a question […]
How to Design an Uninterruptible Power Supply (UPS) Circuit
In this brief tutorial I have explained how to design a customized UPS circuit at home using ordinary components such as a few NAND ICs and a some relays. What is an UPS UPS which stands for uninterruptible power supply are inverters designed to provide a seamless AC mains power to a connected load without […]