In this article we study an op amp based millivolt meter circuit designed to measure AC millivolts accurately, I have explained the details from the following explanation. The circuit shown below can be used to measure DC potentials in the range of milli-volts. The circuit is highly sensitive and is calibrated to measure voltages in […]
Meters and Testers
Simple IC Tester Circuit [Test Digital and Analogue ICs]
The IC Tester is simple to use. You don’t have any switches to configure or lengthy test processes to complete. The universal IC Tester is a static tester, which means this does not dynamically test the IC’s operation. All ICs with up to 20 pins can be tested by this unit. ICs with more than […]
Signal Injector Circuits for Quick Troubleshooting of all Audio Equipment
This simple signal injector circuits I have explained below can be accurately used for troubleshooting and alignment applications of all kinds of audio and high frequency equipment. 1) Using a Single IC 7400 One of the extremely handy devices for repairing audio and high frequency instruments is without question a equipment that will give you […]
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 […]
Simple LED Forward Voltage Drop Tester Circuit
Semiconductor LEDs (Light Emitting Diodes) produce light when current flows through them. In comparison to conventional lighting sources, LEDs offer a number of benefits, including high energy efficiency, extended longevity, and low thermal output. The forward voltage drop of an LED is one of the important factors that affects how well leds performs. We will […]
Grid Dip Meter Circuit
A dip meter or a grid dip meter can be considered as a kind of frequency meter whose function is to determine the resonant frequency of an LC circuit. For this, the circuits don’t have to ‘radiate’ any waves or frequency across each other. Instead, the procedure is implemented simply by placing the coil of […]





