The circuit discussed in this article is of a non-contact mains AC field detector which displays the presence of a mains AC field from a distance of more an 6 inches. Locating Fault in AC Lines without Physical Contact The circuit can be used for locating faults in house wiring without the need of making […]
Sensors and Detectors
DHT11 Humidity, Temperature Sensor: How to Use and Interface with Arduino
We are now going to talk about one small cheap sensor that we call DHT11, and we can use that for measuring humidity and also temperature. You can see that many Arduino people like this sensor because it is very simple and also very low cost, so anybody can buy and try. The DHT11 can […]
Alcohol Detector Meter Circuit using MQ-3 Sensor Module
An alcohol detector is a sensitive device which is able to detect the presence of alcohol molecules or any similar volatile inflammable element in the air and convert it into equivalent level of electrical output. The simple alcohol detector circuit discussed here will accurately sense the emanation of alcohol gas from a selected source, such […]
Fence Charger Animal Contact Detector Circuit with Audible Buzzer
In one of my electric fence charger articles, one reader asked me something interesting. He wanted to know whether a buzzer could be made to sound whenever an animal touches the fence. At first I was thinking about a current sensing method because that looks like the obvious way. But after looking at how electric […]
How to Connect a TSOP1738 IR Sensor
TSOP17XX series devices are advanced infrared sensors having a specified center frequency of operation which makes their detection extremely reliable and foolproof. In this post I have explained how to connect a TSOP series infrared sensor and use it for a specified IR remote control operations. TSOP IR Sensor Specifications A TSOP series of IR […]
Photodiode, Phototransistor – Working and Application Circuits
Photodiodes and phototransistors are semiconductor devices which have their p-n semiconductor junction exposed to light through a transparent cover, so that external light can react and force an electrical conduction through the junction. How Photodiodes Work A photodiode is just like a regular semiconductor diode (example 1N4148) consisting of a p-n junction, but it has […]





