Recently, I installed an antenna for Meshtastic on the 915 MHz band on my balcony. What is it?
Meshtastic is an open-source system for long-range text communication without internet or cellular networks, operating on LoRa radio modules (usually 433 / 868 / 915 MHz bands).
Simply put: it is a decentralized radio-based messenger where devices form a mesh network (cellular network) and forward messages through each other.
š¹ How it works
- You have a small device (e.g., LilyGO T-Beam, Heltec, RAK).
- It connects to your phone via Bluetooth.
- You write a message in the Meshtastic app.
- The message is transmitted via LoRa radio.
- Other nodes:
- receive the message
- retransmit it further until it reaches the recipient.
š No internet needed. No SIM card needed. No operator needed.
I bought a Lilygo T-Beam module for this:
I made an enclosed case for it, provided power, and attached an external antenna. For a while, everything worked perfectly. The case did a great job protecting the device from water. For more reliable reception of the nearest station, I calculated and made a Yagi antenna. I printed it on a 3D printer and used thick copper wire as reflectors. Iām providing the antenna calculations here.
But one day, when the humidity was particularly high, it finally gave out.