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A
Alarm Circuits
Alarm PSU
AM Modulator
AM Transmitter Circuit
AM Receiver
Add-On Current Limiter
Asymetrical Timer
ATL3 Loop Antenna
Audio Circuits
Audio Indicator
Audio Level Meter
Audio Notch Filter
Audio Voice-Over Circuit
Audio VU Meter
Automatic Intruder Alarm
Automatic Repeater
A Collection of Mini-Alarms
Bench Amplifier
Class A//A-B Amplifier
CMOS Single Zone Alarm
Cold Activated Switch
Enhanced Alarm Keypad
Frost Alarm
Gate Alarm
Headphone Amplifier
Miniature Loop Alarm
Modular Burglar Alarm
Motorcycle Alarm
Motorcycle Alarm 2
Motorcycle Alarm 3
Motorcycle Alarm 4
Motorcycle Alarms 5 & 6
MW Active Antenna
Output Adjustable Flyback Converter
Peak Reading Audio Level Meter
Q-Multiplying Loop Antenna
Quadraphonic Amplifier
Radio Wave Alarm
Snore Alarm
SCR Based Burglar Alarm
Soft Switching Amplifier with Tone Controls
TDA 2030 Amplifier
Water Activated Alarm
ZN414 Portable AM Receiver
2 Watt Amplifier
5 Zone Alarm
15 Watt Amplifier

B
Baby Alarm
Band 2 VHF Amplifier
Beat Balance Metal Detector
Bench Amplifier
Bipolar Regenerative Receiver
Boosting Regulator Current
Buzzer Circuit
DC Push Button Motor Control
Decimal to BCD Convertor
Fuse Blown Indicator
Modular Burglar Alarm
Nicad Battery Charger
An SCR Based Burglar Alarm
4 Band Double Tuned Preselector

C
Cable Tester
Camera Switcher
Car Alarm and Immobilizer
Class A//A-B Amplifier
CMOS Single Zone Alarm
Coil Coupled Operation Metal Detector
Cold Activated Switch
Collection of Mini-Alarms
Combinational Conjuring Trick
Conjuring Trick
Connection Tester
Control and Interfacing
Computer Microphone
Crystal Controlled Oscillator by Ramon Vargas
Crystal Test Circuits
Current Limiting Power Supply
Add-On Current Limiter
Boosting Regulator Current
Digital Combination Lock
Doorbell with Counter
Electric Curtains
Electronic Canary
Infra Red remote control extender
Infra Red Remote Control Extender Mark 2 Version
Infra Red remote control tester
Light Detection Circuit
Nicad Battery Charger
Output Adjustable Flyback Converter
Power Control Circuits
Quartz Crystal Test Circuits
Quiz Circuit
Tone Controls
Voltage Comparator Switch
24 Second Shot Clock

D
Dark Activated Switch
DC Motor Reversing Circuit
DC Push Button Motor Control
Decimal to BCD Convertor
Digital Combination Lock
Doorbell for the Deaf
Doorbell with Counter
Doorphone Intercom
Dual Regulated PSU
Dynamic Microphone Preamplifier
Metal Detector
Electromagnetic Field Detector
Light Detection Circuit
Modulation Detector for IR Remote Controls
Negative Ion Detector
Neon Desklamp
Remote Doorbell Indicator
Stereo Line Driver
Surveillance Transmitter Detector
Switch Debouncer
Zener Diode Tester
4 Band Double Tuned Preselector
Audio Line Driver

E
ECM Mic Preamplifier
Electric Curtains
Electronic Canary
Electromagnetic Field Detector
Electronic Siren
EMF Probe with Meter
Enhanced Alarm Keypad
Electronic Metronome
Infra Red remote control extender
Infra Red Remote Control Extender Mark 2 Version
Music and Special Effects
Sound Effects Generator

F
Fast Electronic Fuse
Field Strength Meter
FM Receiver using MPF102
FM Transmitter
FM Transmitter 2
Frost Alarm
Function Generator
Fuse Blown Indicator
Audio Notch Filter
Electromagnetic Field Detector
Output Adjustable Flyback Converter
Simple Field Strength Meter
2 Transistor FM Transmitter

G
Gate Alarm
Gyrator Circuit
Function Generator
Sound Effects Generator

H
Headphone Amplifier
Hi-Fi Preamplifier
HiJack Alarm
High Quality Intercom
Hot Water Indicator
Passive Ethernet Hub

I
Infra Red Link
Infra Red remote control extender Mark 1
Infra Red Remote Control Extender Mark 2
Infra Red Remote Control Extender Mark 3
Infra Red Remote Control Extender mark 4
Infra Red Remote Control Extender Mark 5
Infra Red remote control tester
Infra Red Switch
Insect Repellant
Audio Indicator
Car Alarm and Immobilizer
Control and Interfacing
Doorphone Intercom
Fuse Blown Indicator
High Quality Intercom
Hot Water Indicator
Negative Ion Detector
Remote Doorbell Indicator
Signal Injector and Tracer
6 Input Mixer

J

K
Keypad Circuit
Enhanced Alarm Keypad

L
Laser Communication System
LED Flasher
LED flasher 2
LED Torch
LED Torch 2
Light Detection Circuit
LM317 Voltage Regulator
Logic PSU with Over Voltage Protection
Logic Probe
Low Voltage Preamp
L200 PSU
Add-On Current Limiter
ATL3 Loop Antenna
Current Limiting Power Supply
Miniature Loop Alarm
Model Rocket Lauch Controller
Night Light
Peak Reading Audio Level Meter
Q-Multiplying Loop Antenna
Stereo Line Driver
Triac Light Controller
Water Level Alarm

M
Magic Wand
Metal Detector
Milligauss Meter
Miniature Loop Alarm
Miscellaneous Circuits
MK484 Complete Receiver
Model Rocket Lauch Controller
Modular Burglar Alarm
Modulation Detector for IR Remote Controls
Monitor Splitter
Motorcycle Alarm
Motorcycle Alarm 2
Motorcycle Alarm 3
Motorcycle Alarm 4
Motorcycle Alarms 5 & 6
Multi Rocket Launcher
Music and Special Effects
MW Active Antenna
Beat Balance Metal Detector
Coil Coupled Operation Metal Detector
Collection of Mini-Alarms
Computer Microphone
DC Push Button Motor Control
DC Motor Reversing Circuit
Digital Combination Lock
Dynamic Microphone Preamplifier
ECM Mic Preamplifier
Electronic Metronome
EMF Probe with Meter
Field Strength Meter
Peak Reading Audio Level Meter
Q-Multiplying Loop Antenna
Room Monitor
Simple Field Strength Meter
Speaker Microphone
Temperature Monitor
6 Input Mixer
555 Monostable Circuit

N
Negative Ion Detector
Negative Voltage Load Switch
Neon Desklamp
Nicad Battery Charger
Night Light
Audio Notch Filter

O
Output Adjustable Flyback Converter
Over Voltage Protection for LM317
Crystal Controlled Oscillator by Ramon Vargas
Logic PSU with Over Voltage Protection
Sound Operated Switch
Square Wave Oscillator

P
Passive Ethernet Hub
Peak Reading Audio Level Meter
Periodic Timer
Perimeter Alarm
Porch Light Switch
Pot Plant Power
Power Control Circuits
Privacy Circuit
Pulse generator
Current Limiting Power Supply
DC Push Button Motor Control
Dual Regulated PSU
Dynamic Microphone Preamplifier
ECM Mic Preamplifier
EMF Probe with Meter
Hi-Fi Preamplifier
Logic Probe
Logic PSU with Over Voltage Protection
Low Voltage Preamp
L200 PSU
MW Active Antenna
Soft Start Power Supply
UHF Preamplier
Uninterruptable Power Supply
Unregulated PSU
ZN414 Portable AM Receiver
4 Band Double Tuned Preselector
1.3V Power source
9V 2A PSU
12V 30A PSU
13.8V 20A PSU

Q
Quadraphonic Amplifier
Quartz Crystal Test Circuits
Quiz Circuit
Q-Multiplying Loop Antenna
High Quality Intercom

R
R5000 Interface
Radar Detector
Radio Wave Alarm
Regulated 12v PSU
Remote Doorbell Indicator
RF Circuits
Room Monitor
AM Receiver
Automatic Repeater
Bipolar Regenerative Receiver
Boosting Regulator Current
DC Motor Reversing Circuit
Dual Regulated PSU
FM Receiver using MPF102
Infra Red remote control extender
Infra Red Remote Control Extender Mark 2 Version
Infra Red remote control tester
MK484 Complete Receiver
Model Rocket Lauch Controller
ZN414 Portable AM Receiver
ZN414 SW Receiver
Variable Voltage Regulator

S
Short Wave Regenerative Receiver
Signal Injector and Tracer
Simple Field Strength Meter
Sine Wave Generator
Small Variable Power Supply
Snore Alarm
Soft Start Power Supply
Sound Operated Switch
Speaker Microphone
Square Wave Oscillator
Stereo Line Driver
Supply Voltage Indicator
Surveillance Transmitter Detector
Switch Debouncer
Camera Switcher
Cold Activated Switch
Dark Activated Switch
Electronic Siren
Field Strength Meter
Music and Special Effects
Sound Effects Generator
Sound Effects Generator 2
Uninterruptable Power Supply
Voltage Comparator Switch
ZN414 SW Receiver
24 Second Shot Clock

T
TDA 2030 Amplifier
Telephone in Use monitor
Temperature Monitor
Tone Controls
Triac Light Controller
TV Transmitter
Conjuring Trick
FM Transmitter
Infra Red remote control tester
LED Torch
AM Transmitter Circuit
Cable Tester
Connection Tester
Asymetrical Timer
Periodic Timer
Quartz Crystal Test Circuits
Soft Switching Amplifier with Tone Controls
Surveillance Transmitter Detector
Zener Diode Tester
2 Transistor FM Transmitter
2 Transistor Transmitter
24 Hour Timer
4 Band Double Tuned Preselector
4 Transistor Transmitter
5 to 30 minute Timer

U
UHF Preamplier
Ultrasonic Dog Whistle
Uninterruptable Power Supply
Universal DC-DC Convertor
Universal PSU
Unregulated PSU

V
Variable PSU
Variable PSU 2
Variable Voltage Regulator
Voltage Comparator Switch
Voltage Controlled Switch using 555
Audio Voice-Over Circuit
Band 2 VHF Amplifier
Logic PSU with Over Voltage Protection
Low Voltage Preamp
Negative Voltage Load Switch
Small Variable Power Supply
Supply Voltage Indicator

W
Water Activated Alarm
Water Activated Relay
Water Level Alarm
Wien Bridge Oscillator
Hot Water Indicator
Magic Wand
Radio Wave Alarm
Short Wave Regenerative Receiver
Square Wave Oscillator
Ultrasonic Dog Whistle
2 Watt Amplifier

X

Y

Z
Zener Diode Tester
ZN414 Portable AM Receiver
ZN414 SW Receiver
5 Zone Alarm
CMOS Single Zone Alarm


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