Magic Lights Circuit using Bi-Colour LED

This is the magic lights circuit which use bi-colour LED as the output to provide the light. The circuit uses 14 bi-colour (red and green) LEDs having 3 terminals each. Various dancing colour patterns are generated utilizing this circuit considering that each LED can create three various colours. The middle terminal (pin 2) of the LEDs will be the common cathode pin that is grounded. When a positive voltage is applied to pin one, it emits red light. Similarly, when positive voltage is applied to pin 3. it emits green light. And when positive voltage is simultaneously applied to its pins 1 and 3, it emits amber light.

Simple Audio Booster

This is a simple and low-cost audio booster circuit design. The circuit is based on general purpose amplifier and switches, 2N3392 transistor packed in TO-92. This circuit should be installed before power amplifier module.

Cricket Chirping Sound Generator

This is the circuit diagram of cricket chirping sound generator based on IC 4060, a 14 stage ripple counter and oscillator IC. A suitable audio wave form is produced by IC2 and related electronic components, driving the mini speaker through Q1. To allow a more real-life behavior, the chirp is interrupted in a pseudo-casual way by two timers built around IC1C and IC1D, whose outputs are mixed into IC1B and further time-delayed by IC1A, driving the reset pin of IC2.