Batteryless Door Alarm Bell(Multi Purpose Alarm Bell) @ThomasKim

Batteryless Door Alarm Bell(Multi Purpose Alarm Bell) @ThomasKim

Uploaded March 2017 | Updated September 2026, 2 hours ago

This is a simple Batteryless Door Alarm Bell.
DC 3V motor : From CD ROM
DC 110V Motor : From Massage machine
Limit Switch : From Laser Printer Circuit board

Batteryless Door Alarm Bell(Multi Purpose Alarm Bell)

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Batteryless Door Alarm Bell(Multi Purpose Alarm Bell)