Raspberry Pi solenoid alarm bell:
Controlling components on a separate power supply from the Raspberry Pi. This project uses a PIR sensor, an IR range sensor, a solenoid, a reception bell and some bright LEDs to form a proximity alarm system.
I’m not sure if there’s any real practical use for what I’ve made here but some of the techniques, both with the electronics and the software may be of interest. It was fun making it anyway!
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