Electonic Lock with 4 Combination keys

20 W Power Amplifier Circuit with high Quality Out put

Simple high power FM transmitter Circuit with 2N2222

This circuit is a simple two transistors (2N2222) . No license is required for this transmitter. If powered by a 9 volt battery and used with an antenna no longer than 12 inches, the transmitter will be within the FCC limits. The microphone is amplified by Q1. Q2, C5, and L1 form an oscillator that operates in the 80 to 130 MHz range.

10 Amp 13.8 Volt Power Supply Circuit Design

Swing Machine Motor Speed Controler Circuit

Automatic fan controller Unit

Numeric Water Level Indicator Circuit

The numeric water level indicator circuit works off 5V regulated power supply. It is built around priority encoder IC 74HC147 (IC1), BCD-to-7-segment decoder IC CD4511 (IC2), 7-segment display LTS543 (DIS1) and a few discrete components.