The 4 LED temperature indicator circuit discussed here is very useful for getting a visual information regarding the state of temperature which is to be monitored. Circuit Operation In the circuit temperature status is displayed using four LEDs. – A green LED, indicating that the temperature is in the desirable level- Two yellow LEDs are […]
Archives for 2015
Flashing Red, Green Railway Signal Lamp Circuit
In this post I have explained how to make a simple railway signal lamp which can be used by the guards for providing a handheld signalling to the various trains with the many specified signalling modes. The idea was requested by Mr. Bala. Technical Specifications I need a project design for railway led signalling light . […]
How to Make Ultrasonic Remote Control Circuit
This ultrasonic remote control circuit can be used to switch and control any appliance ON/OFF through a relay in the receiver circuit. Written by: S.S. Kopparthy Using Ultrasonic Waves This circuit is a different one that uses ultrasonic sound waves whose frequency ranges from 40 KHz to 50 KHz. These waves can’t be heard by […]
Infrared Remote Controlled Door Lock Circuit
In this article I have explained about a simple infrared remote controlled door lock circuit which can be used for securely locking doors through unique foolproof IR frequencies. The proposed infrared remote controlled door lock circuit can be used for locking your main door, gate, garage door, shop or any entrance which may need a […]
How to Make an ATX UPS Circuit with Charger
In this post I have explained a simple ATX UPS circuit with an automatic charger for enabling an automatic changeover from mains to battery power during mains failures and for ensuring an uninterruptible operation of the ATX load. Technical Specifications I´m interested in your site and there are a lot good ideas. But for my […]
PWM Motor Soft Start Circuit to Prevent High Consumption during Power Switch ON
In this post I have explained an effective PWM motor soft start circuit which can be used for enabling heavy motors with a soft start and thus prevent the equipment from drawing dangerous high currents. Why a Soft Start High wattage motors such pump motors or other forms of heavy industrial motors tend to draw […]





