• 1-100 TransistorCircuits
• 101-200 TransistorCircuits

Colin Mitchell
colin@elechelp.com

Here is a list of some of the contents - more has been added:

• Ammeter 0-1A

• Automatic Garden Light

• Automatic Light

• Bench Power Supply

• Boom Gate Lights

• Boxes

• Buck Converter for LEDs 48mA

• Buck Converter for LEDs 170mA

• Buck Converter for LEDs 210mA

• Cable Tracer

• Clock - Make Time Fly

• Colpitts Oscillator

• Constant Current Source

• Continuity Tester

• Dancing Flower

• Door-Knob Alarm

• Dynamic Microphone Amplifier

• Electronic Drums

• Fog Horn

• FRED Photopopper

• Gold Detector

• Guitar Fuzz

• Hartley Oscillator

• Heads or Tails

• Hearing Aid Constant Volume

• Hearing Aid Push-Pull Output

• Hearing Aid 1.5v Supply

• Hee Haw Siren

• IC Radio

• LED Detects Light

• LED Flasher 1-Transistor

• LED Torch with Adj Brightness

• LED Torch with 1.5v Supply

• Lie Detector

• Light Alarm-1

• Light Alarm-2

• Light Alarm-3

• Light Extender for Cars

• Listener - phone amplifier

• Logic Probe - Simple

• Logic Probe with Pulse

• Make Time Fly!

• Making 0-1A Ammeter

• Metal Detector

• Microphone Pre-amplifier

• Motor Speed Controller

• Movement Detector

• Multimeter - Voltage of Bench Supply

• Music to Colour

• On-Off via push Buttons

• Phaser Gun

• Phone Alert

• Phone Tape-1

• Phone Tape-2

• Phone Transmitter-1

• Phone Transmitter-2

• Phase-shift Oscillator

• Resistor Colour Code

• Robo Roller

• Robot

• Robot Man - Multivibrator

• Schmitt Trigger

• SCR with Transistors

• Second Simplest Circuit

• Signal by-pass

• Signal Injector

• Simple Logic Probe

• Siren

• Solar Engine

• Solar Engine Type-3

• Solar Photovore

• Sound to Light

• Sound Triggered LED

• Speaker Transformer

• Spy Amplifier

• Strength Tester

• Sun Eater-1

• Sun Eater-1A

• Super Ear

• Ticking Bomb

• Touch Switch

• Train Throttle

• Transistor Pinouts

• Transistor Tester-1

• Transistor Tester-2

• Trickle Charger 12v

• Walkie Talkie

• Walkie Talkie with LM386

• Walkie Talkie - 5 Tr - circuit 1

• Walkie Talkie - 5 Tr- circuit 2

• Worlds Simplest Circuit

• White LED Flasher

• White LED with Adj Brightness

• White Line Follower

• Zener Diode (making)

• 0-1A Ammeter

• 1.5v to 9v Inverter

• 5 LED Chaser

• 5 Transistor Radio

• 5v Regulated Supply from 3v

• 6 Million Gain

• 6 to 12 watt Fluoro Inverter

• 12v Relay on 6v

• 12v Trickle Charger

• 20watt Fluoro Inverter

• 27MHz Door Phone

• 27MHz Transmitter

• 27MHz Transmitter - no Xtal

• 27MHz Transmitter-Sq Wave

• 27MHz Transmitter-2 Ch

• 27MHz Transmitter-4 Ch

• 27MHz Receiver

• 27MHz Receiver-2

• 303MHz Transmitter

Update: The capacitor used in the tank circuit of the following project in the 200Transistor Circuits eBook, is 39p and the coil is 13 turns. It can be replaced with 11 turns of 0.25mm wire on 3mm dia slug 7mm long: