Newest circuit diagrams

Hijack Alarm

The first circuit was designed for the situation where a hijacker forces the driver from the vehicle. If a door is opened while the ignition is switched on - the circuit will trip. After a few minutes delay - when the thief is at a safe distance - the alarm will sound and the engine will fail.

Hi-Fi Preamplifier

This circuit has an exceptionally fast high frequency response,as demonstrated by applying an 100kHz squarewave to the input.

Clap Relay

Clap sensitive on-off Relay. 3V Battery operated, small portable unit

Whistle Responder

Beeps when hears your whistle. A gadget suitable for key-holders, games etc.

Water Activated Relay

In his circuit Marin has used two transistors wired as a high gain compound pair.

Dancing LEDs

LED sequencer: follows the rhythm of music or speech. 9V Battery-operated portable unit

Circuit Board Tester

Indicates the basic integrity of a printed board. Self-powered - 3 to 30V range.

Water Pump Relay Control

Water reservoir automatic level control. Simple circuitry - 12V supply

Mini Metronome

Linear scale - Small size. 40 to 208 beats per minute

L200 Power Supply

Power supply with variable voltage and fixed current regulation made using the ubiquitous L200C regulator.