This program will notify you when someone opens your outdoor mailbox. Program features:
- Notifications via LED, internal web site, Telegram or Google Home
- Support for multiple mailboxes (on receiver side)
- Log of events
Hardware part is made with a pair of ESP-01(S), which rely on HC-12 radio modules for communication using hand-made antennas. Classical reed switch is used for door opening detection. Radio link works reliably at 150 m distance with quite some obstacles (trees and bungalow type houses). Remote (mailbox) module is powered with one 14250 battery lasting for eight months on average (depends on the range and usage; the longest run so far has been 13.5 months). The schematics are simple, especially for the receiver part.
Receiver (left) and transmitter (right) before installation, fit with some early testing antennas (enclosure - TicTac):
Consult Wiki for Getting Started, Schematics and details of Operation.
January 2022: v3 is planned with important redesign of remote module. It will bring a PIR sensor to detect letters and small parcels and a more suitable controller (ATtiny instead of ESP-01S).