Multi-Zone Burglar Alarm Circuits

Two-Zone Burglar Alarm
An Expandable Multi-Zone Modular Burglar Alarm
A One-Time-Only Burglar Alarm
An Expandable SCR Based Burglar Alarm
An Expandable Transistor Based Burglar Alarm
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Single-Zone Burglar Alarm Circuits

A Transistor Based Single Zone Alarm
A Cmos Based Single Zone Alarm
A Simpler Cmos Single Zone Alarm
A Cmos 4060 Burglar Alarm
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Battery-Powered Alarm Circuits

A Dozen Small Cmos Alarm Circuits
Four Small Transistor Alarm Circuits
A Simple Shop-Door Alarm
A Simple Fire-Door Alarm
A Shed / Garage Alarm
An Enhanced Shed / Garage Alarm
A Battery-Powered One-Time-Only Burglar Alarm
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Alarm Control Keypads

A 4-Digit Alarm Control Keypad
A 5-Digit Alarm Control Keypad
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Universal Keypad-Controlled Switches

A 4-Digit Keypad Controlled Switch
Keypad Controlled Switch No. 2
Keypad Circuit - With Parallel Code Entry
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Keypad-Operated Door-Lock Release

Electronic Door Release
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Power Supply Circuits

An Alarm Power Supply With Battery Back-up
A Current Limiting Bench Power Supply
An Add-On Current Limiter For Your PSU
A Transformerless Power Supply
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Automobile Alarm Circuits

A Cmos Based Vehicle Anti-Theft Alarm
Two Cmos Based Vehicle Anti-Hijack Alarms (300k Zip File)
Vehicle Anti-Hijack Alarm No. 3
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Motorcycle Alarm Circuits

A Transistor Based Motorcycle Alarm
A 555 -Timer Based Motorcycle Alarm
A Cmos Based Motorcycle Alarm
A Simple Transistor Based Motorcycle Alarm
Two Simple Relay Based Motorcycle Alarms
Motorcycle Alarm No.7
Motorcycle Alarm No.8
One-Time-Only Motorcycle Alarm
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Timer Circuits

Cmos 4017 Sequential Timer
Two Cmos Based 24-Hour Timers
A Regularly Repeating Interval Timer
Repeating Interval Timer No.2
Repeating Timer No.3
Repeating Timer No.4
Repeating Timer No.5
Repeating Timer No.6
Repeating Timer No.7
Repeating Timer No.8
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Battery Powered LED Circuits

Three Fake Alarms
Three Flashing LED Doorbells
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Switching Circuits

Electronic Toggle Switch No.1
Electronic Toggle Switch No.2
Electronic Toggle Switch No.3
Cell Phone Controlled Toggle Switch
Two Light Controlled Relays
Two Temperature Controlled Relays
Thermostat With Adjustable Hysteresis
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Miscellaneous

An Infra-Red Remote Control Extender
A Decimal to BCD Decoder
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Practical Section

How To Choose The Right Parts
How To Identify A Relay's Pin Configuration
How To Identify A Transistor's Pin Configuration - And Polarity
How To Cure False Alarms.
Make Your Own Stripboard
Designing Stripboard Layouts
How To Convert Any Stripboard Layout - Into A PCB
Converting More Complex Layouts - To PCBs
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Tutorials

An Introduction to the Cmos 4001
An Introduction to the Cmos 4011
A Beginner's Guide To Cmos Timers
An Introduction to the Complementary Latch
How To Measure the Switching Voltage And Hysteresis Of A Cmos Gate
Predicting Thermistor Values At Different Temperatures
How To Calculate The Temperature Constant (Beta) Of A Thermistor