Alarms and security circuit diagrams
This is a simple motorcycle alarm - with a time limit on the siren. While the thief continues to move the bike - and the normally-open trigger switch continues to open and close - the siren will continue to sound. When the bike stops moving - the siren will cut-off.
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Warns if an object is moved, Small gadget - 9V Battery supply
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This is a complete alarm system with 5 independent zones suitable for a small office or home environment. It uses just 3 CMOS IC's and features a timed entry / exit zone, 4 immediate zones and a panic button. There are indicators for each zone a "system armed" indicator
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This circuit features an intermittent siren output and automatic reset. It can be operated manually using a key-switch or a hidden switch; but it can also be wired to set itself automatically when you turn-off the ignition. By adding external relays you can immobilize the bike, flash the lights etc.
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This switch will suit the Modular Burglar Alarm circuit. However, it also has other applications. The Keypad must be the kind with a common terminal and a separate connection for each key.
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This is a simple - easy to build - transistor based motorcycle alarm. It's designed to work at 12-volts. But - if you change the relay for one with a 6-volt coil - it'll protect your "Classic Bike". The standby current is virtually zero - so it won't drain your battery.
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A remote listening circuit. The area to be monitored is connected via a cable and allows remote audio listening.
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This circuit features automatic Exit and Entry delays and a timed Bell Cut-off. It has provision for both normally-closed and normally-open contacts, and a 24-hour Personal Attack/Tamper zone.
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This is a two-zone alarm - with automatic exit, entry and siren cut-off timers. It can be triggered by the usual types of normally-closed input devices - such as magnetic reed contacts - foil tape - PIRs etc. I've used a 12-volt supply in the diagram - but the circuit will work at anything from 9 to 15-volts. All you need do is select a siren, buzzer and relay to suit the voltage you want to use.
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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. But it's easy to add a normally-open trigger.
When the alarm is activated - the siren will sound for a fixed length of time. Then it will switch off - and remain off. The alarm will not re-activate.
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