Basic Joule Thief led torch circuit

A series of LEDs that turn on and off in a precise sequence, creating a calming and hypnotic effect. Various LED chaser, scanner, and sequencer circuits exist, utilizing discrete transistors, logic integrated circuits (ICs), or microcontrollers. However, a common limitation...

single transistor flyback Joule Thief circuit

This circuit is a single transistor flyback (Joule Thief) circuit that features a third coil. With it, flash duration and brightness are significantly enhanced. The single transistor flyback circuit, commonly known as a Joule Thief, is designed to efficiently convert low...

Bi-Color Indicator Circuit

With switch SI open, base bias is supplied to transistor Q2 through a voltage divider formed by resistors R2 and R3, which activates the green element of the LED. This indicates that power is being supplied to the project. When...

Dicing With LEDs circuit

Every dedicated DIY enthusiast creates their own electronic dice using LEDs as indicators. This eliminates the need to physically roll dice; simply pressing a button activates the electronic mechanism. The design incorporates safeguards to prevent manipulation for improved outcomes, ensuring...

BA6104 Five-digit LED level meter driver IC Basic Application Circuit

BA6104 is a five-digit LED level meter driver integrated circuit (IC) that features a basic application circuit. The input stage employs a PNP transistor with a composite base input, resulting in high input impedance. The output stage is configured as...

Positive and negative from a battery LT1010

A common need in many systems is to obtain positive and negative supplies from a single battery. Where current requirements are small, the circuit shown is a simple solution. It provides symmetrical +&- output voltages, both equal to one half...

LED Crystal Tester

Transistor Q1, a 2N3563, and its associated components form an oscillator circuit that will oscillate if, and only if, a good crystal is connected to the test clips. The output from the oscillator is then rectified by the 1N4148 signal...

One Amp Battery Charger

When this battery charger was purchased in 1970, it was not anticipated that it would still be relevant today. At that time, the owner had an old car with a weak battery that struggled to start in cold weather, prompting...

LED Blown AC Fuse Indicator

LED Blown AC Fuse Indicator Circuit Diagram. This circuit monitors an AC fuse. In this circuit, the LED indicator shows whether or not the fuse is blown. The LED Blown AC Fuse Indicator Circuit is designed to provide a visual indication...