ELECTRONIC CIRCUITS

WELCOME TO OUR CIRCUITS PAGE

Most of these circuits I have designed and tested. Some are copies of circuits demonstrating a neat or clever way of functioning. I don't take any responsibility for anyone using them and feel free to adjust or modify them as you wish.

Some PDF's have PCB track layouts generated for the circuit, ready for construction using UV photo-etching. Remember check the scale/size of the drawing after you have printed it out to ensure the components like ICs will fit correctly.

There are LiveWire circuits that where possible simulate the function of the circuit. (Available from New Wave Concepts), Apologies in advance, some of these pages really need updating.


Or try designing and building your own circuits with CIRCUIT BRICKS and CIRCUIT BLOX.

CIRCUIT BRICKS

CIRCUIT BLOX

Select a category below or scroll down to browse:

Audio

Games

Hobbies

Timers

Test

Misc


AUDIO

555 SIREN GENERATOR

A simple design from two 555 timers - this is versatile and very loud.

AUDIO PRE-AMPLIFIER

A low signal pre-amp using an op-amp from a single supply.

AUDIO CAR POWER AMPLIFIER

A 20 Watt bridged amplifier for 12v supply, using the TDA2005 IC.

AUDIO 7 WATT AMPLIFIER

A simple 12v audio amplifier circuit based around LM383 IC- NOT TESTED.

AUDIO 14 WATT AMPLIFIER

Single supply and split supply versions of the popular TDA2030 IC amplifier.

AUDIO 32 WATT AMPLIFIER

Single supply and split supply versions of the popular TDA2050 IC amplifier.

GUITAR FUZZ AMPLIFIER

A classic fuzz amplifier circuit powered by a PP3 battery - NOT TESTED.

BASS & TREBLE AMPLIFIER

A PP3 battery circuit providing +/- 3dB bass/treble cut and boost.

BASS & TREBLE AMPLIFIER 2

An op-amp circuit providing improved bass/treble cut and boost.

BASS BOOSTER

An op-amp filter to boost/cut bass audio frequencies.

HIGH PASS ACTIVE FILTER

A Sallen Key filter design. Ideal for tone controls and tweeter/midrange crossover.

LOW PASS ACTIVE FILTER

A Sallen Key filter design. Ideal for demodulation and bass crossover.

PARAMETRIC EQUALISER

Tailor your audio with this variable frequency cut/boost filter.

RING MODULATOR

Useful for sound effects - simple in design, based on 2 transformers - NOT TESTED.

SOUND ACTIVATED SWITCH

A useful circuit for many applications.

THEREMIN

A simple version of this device, enables you to literally play a tune with a wave of the hand!!.

TRIANGLE WAVE ASTABLE

A useful replacement for a sine wave generator, has AC/DC triangle output.

VOLTAGE CONTROLLED AMPLIFIER

Useful circuit that can be configured as a VCA, modulator and multiplier.
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GAMES

RANDOM NUMBER GENERATOR

Generate a number from 1 to 49, was designed for the original Lotto game.

42 LED CHASER

Simple multiplexing,, can be easily adapted for up to 100 LEDs

4 WAY ROULETTE

A simple roulette with bulbs and just 4 numbers.

BINGO

Generates a random number from 1 to 90.

DIGITAL DICE

Single and double die circuits using logic and LEDs.

HEADS OR TAILS

A hand held Heads or tails coin-toss decision maker using 2 LEDs.

ROULETTE

A 0-36 LED full range roulette wheel circuit.

SCALEXTRIC RACE STARTER

Recreates the light sequence at the start of an F1 race.

STEADY HAND GAME

A Steady Hand game with LEDs and buzzer, giving up to 9 chances.

SURVIVAL GAME

An addictive game of skill, modified from an old electronics magazine.

SCOREBOARD 1-DIGIT

An addictive game of skill, modified from an old electronics magazine.

SCOREBOARD 2-DIGIT

A two digit scoreboard using 7-segment displays.
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HOBBIES

10 CHANNEL LIGHT DIMMER

A controller to dim up to 10 12v light bulbs independently.

CONSTANT CURRENT GENERATOR

A constant current generator based around LM317 voltage regulator.

BATTERY CONDITIONER

Keeps unused lead-acid batteries fit and healthy when not in use.

CAR IMMOBILISER

An immobiliser with coded input keypad, designed to protect car ignitions.

COMBINATION LOCK

A digital lock with keypad and relay outputs. Based around UA3730 IC.

COMBINATION LOCK 2

A combination lock using 3 buttons and common logic ICs.

DIRECTIONAL SPEED CONTROLLER

Forward and reverse control using our RC Speed Controller IC.

MOTOR SPEED CONTROLLER

A speed controller based on triangle wave astable and comparator.

FRIDGE ALARM

A light triggered alarm for catching the midnight snackers.

FRIDGE ALARM 2

An improved version that produces a pulsed tone.

RC SPEED CONTROLLER

Fully functional controller for small radio controlled vehicles.

H-BRIDGE BIPOLAR DRIVER

An H-bridge driver ideal for motor directional speed control.

INTELLIGENT BATTERY CHARGER

Charges a battery 1.2v or 7.2v while monitoring battery voltage.

AUTOMATIC BATTERY CHARGER

Set it and leave it. Completes a one off charge for 2-3 hours.

TANK HEATER

A PWM tank heater for plants or fish, or anything.
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TIMERS

24 HOUR CLOCK

A 24 hour clock using logic, counters and 7 segment displays.

24 HOUR TIMER

A one off/cyclic 12 or 24 hour timer.

EGG TIMER

A adjustable 3 minute egg timer with pulsed sound.

FISH FEEDER

A timer that activates briefly every 1,2 or 4 hours.

SCALEXTRIC LAP TIMER

Times alternate laps in 1/100's of a second using a light sensor.

VERSATILE TIMING IC

A pre-programmed PIC with a range of output timings.
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TEST & MEASUREMENT

20 LED VU METER

A 70mm high, dual 7-segment displays from 5mm LEDs.

BATTERY METER

A 10 LED scale meter for testing batteries from 1.2 to 12v.

FREQUENCY TO VOLTAGE

LM2917/N8 frequency to voltage converter circuits.

STROBE LIGHT

An LED strobe light using transistors.

STROBE LIGHT 2

An LED strobe with external trigger for camera flash.

RPM METER

Originally for 4-stroke engines with points, easily adapted.

SERVO TESTER

PWM circuit to test and control RC servos.
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MISCELLANEOUS

LARGE DUAL 7-SEG DISPLAY

A 70mm high, dual 7-segment displays from 5mm LEDs.

12v LAMP DIMMER

A PWM circuit for dimming lamps up to 30W.

AUTO BILGE SENSOR

Keep that bay clear with an auto bilge pump controller.

DOG WARDEN

Raises the alarm if your pet goes out of range.

VOLTAGE INVERTER

Generate a negative supply for use with op-amps and audio.

KEYPAD DECODER

A logic exercise to decode a keypad into BCD.

NITE RIDER

Recreate the 80's look with this light chaser.

MINI NITE RIDER

A mini chaser using bulbs instead of LEDs..

REMOTE BEEPER

A mini chaser using bulbs instead of LEDs..
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