Tag Archives: Security

KeyLock

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Devices known as electrical key-lock can de found in many versions, but I will demonstrate you another interesting workaround of that device. Specificity of that device is a new way to read more keys using only one input of microcontroller. As you can see I used an analog to digital… Read more »

Led Sensor

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Introduction From the beginning, Leds are used in many applications for signalization purposes. For what else can be Led used except for signalization or lighting? You can use it in another way, and some times that may be very useful. Usual Leds can be used as ambient light sensors, where… Read more »

A Battery Powered Burglar Alarm Circuit – With A Timed Siren

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Circuit: Ron J Email Ron Description: This is a single zone alarm – with independently adjustable Exit, Entry and Siren Cut-Off timers. It will accommodate the usual types of normally-closed input devices – such as magnetic-reed contacts, foil tape and PIRs. When the alarm is activated – the Siren will… Read more »

A Cmos 4060 Burglar Alarm Circuit – With A Timed Siren Cut-O

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Circuit: Ron J Email Ron Description: This is a single zone alarm – with automatic exit, entry and siren cut-off timers. It will accommodate all the usual types of normally-closed input devices – such as magnetic-reed contacts – foil tape – PIRs etc. When the alarm is activated – the… Read more »

Fridge door Alarm Circuit Diagram

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Beeps if you leave open the door over 20 seconds 3V battery operation, simple circuitry Circuit diagram: Parts: R1 10K 1/4W Resistor R2 Photo resistor (any type) R3,R4 100K 1/4W Resistors C1 10nF 63V Polyester Capacitor C2 100µF 25V Electrolytic Capacitor D1,D2 1N4148 75V 150mA Diodes IC1 4060 14 stage… Read more »