In this touch operated potentiometer circuit we have two touch pads, which produce a slowly increasing voltage at the output when one touch pad is touched, and a decreasing voltage when the other touch pad is touched. When the touch contact is removed the voltage holds at that particular increased or decreased level “permanently”. Touch […]
Sensors and Detectors
Simple Soil Moisture Tester Circuit with a Single IC 741
A very simple mud or soil moisture tester circuit can be built by using a single opamp and a few passive components, I have explained the details through the following article. Circuit Objective After water and sunlight the earth or the soil is the next most important natural gift that this planet has provided us […]
Make this Touch free Faucet Circuit for Hands-free Tap Control
A very simple touch free faucet circuit or touch free automatic tap circuit can be built using as little as an IC 555 and a few passive components, in order to implement a contact less water supply operation from the attached facet or the tap. Drinking Water is Precious Pure drinking water which we normally […]
Material Storage Level Controller Circuit
In this post I have explained a simple material storage level controller circuit which can be used for automatically activating and deactivating a storage filling motor whenever the storage container is filled to its stipulated threshold level. The idea was requested by Mr Sladjan. Circuit Objectives and Requirements I need help with the engine control […]
Simple Shadow Sensor Alarm Circuit
This shadow detector circuit operates using two LDRs and effectively detects the difference between the light levels and triggers a loud audible warning siren. In circuits which uses a single LDR (photoresist), the detection may not be as sharp as with two LDRs discussed here.Operational details of the shadow detector circuit may be studied as […]
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 […]





