In this article I have explained how to build a simple bicycle speedometer circuit which can be used to measure the speed of the bicycle. Video Demonstration What is a Bicycle Speedometer, How it Works Bicycle speedometer is a device which checks the rotation per minute of the bicycle wheel and displays the results over […]
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Light Meter Circuit with LED Bar Graph
In this article I have explained 3 different light meter circuits for measuring power of light. In the first method we will use only a solar cell and a multimeter, in the second method we will use an op amp and a moving coil meter, and in the third method we will see how a […]
LED Oscilloscope Circuit
The simple LED oscilloscope circuit I have explained in this article can be used for analyzing low frequency waveform through a 10 x 10 LED matrix display. Due to the involvement of only 100 LEDs in the display board, the resolution is low, and the waveform display clarity is not so impressive. Yet, this LED […]
Anti Spy RF Detector Circuit – Wireless Bug Detector
A anti-spy or bug detector circuit is a device that detects hidden wireless electronic devices such as wireless microphones, spy cameras, Wi-Fi devices, GPS trackers or any gadget that emits some kind of radio frequency (RF). The proposed design can be specifically used as: Overview Also called anti spy RF sniffer, these are usually used […]
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 […]
Wireless Music Level Indicator Circuit
A wireless music level indicator is an electronic device built for sensing the varying levels of a music signal and convert it into corresponding levels of illumination over an LED array bar. This simple circuit will create dazzling LED light effect by detecting any music frequency in the atmosphere and by illuminating a 10 LED […]