In this video I show how to build devices which do not use any energy during "deep sleep" and so can be used for a long time. The only prerequisite: A mechanical activation through a button or a magnet.

Links:
ESP8285: https://www.itead.cc/wireless/psf-a85...
Reed Relay: https://www.aliexpress.com/item/10Pcs...

If you want to support the channel and buy from Banggood: https://bit.ly/2jAQEf4 (no additional charges for you)
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