The semiconductor tester circuit I have explained below performs continuity tests on SCRs, bipolar transistors, and diodes. How the Circuit Works A squarewave oscillator with a frequency of about 350 Hz is produced by a couple of IC 4049 gates, U1a along with U1b, R1, R2, and C1. The complementary outputs required for testing both NPN and […]
Newly Updated Circuit Projects:
What is Constant Current Source – Facts Explained
In this post I will try to analyze what is constant current source and how it affects a load, or how it may be used with a load correctly for achieving the most efficient results. The following discussion between me and Mr. Girish will clearly explain what is CC or how constant current operates. How […]
Build this Subwoofer Amplifier Circuit [Mini Ground-Shaker]
A subwoofer amplifier is basically a power amplifier designed to filter and extract the low frequency content from the input audio signal and amplify it to the desired levels. This allows a sound reproduction that is enhanced with deeper bass, generating a concert hall like, or an immersive theater like sound effects. By: Sania D’souza […]
Simple Temperature Indicator Circuits using Thermistors
A thermometer may be required for the precise measurement of temperatures. However, in many cases, an absolute value isn’t required and a relative estimate is sufficient. For example, the consumer may be alerted to the fact that an electric drill or vacuum cleaner is becoming hot, through a basic LED illumination, or through changing color […]
IC 741 Power Supply Circuits
In this post I have explained how to make simple yet fully stabilized and regulated, variable power supply circuits using the IC 741 op amp. Three versions of the 741 power supplies are I have explained below: Simple Variable IC 741 Power Supply The first figure below exhibits a IC 741 based simple variable voltage […]
3 Solid-State Single IC 220V Adjustable Power Supply Circuits
These AC to DC power supplies use a single chip to convert mains 220 V or 120 V input AC into 12 V or 5 V DC without depending on a transformer. Three simple yet efficient 220V single chip based solid state transformerless adjustable solid-state power supply circuits are discussed here. The first one works […]





