Long Range Data Collection with Relay from RFM69 to LoRa

[brandock]

My father is using Open Energy Monitor to monitor a heat pump in his new machine shop. There's no internet access in the shop, so he was taking his laptop out there periodically and downloading the emonCMS data via browser. I'd wanted to set up a relay for him so that the Pi base station could be in his house. It would go: OEM sensors in shop --> Moteino with RFM69CW in the shop<----->Moteino with LoRa in the shop<-----> Moteino with LoRa in the house ---> OEM base station. I think of this as a "relay".

It works! The shop is about 70 meters from the house with some other building in between. The packets are arriving as expected in the house for over a month now.

I did this using three Moteinos.
Moteino 1: RFM69 radio receiving packets and repeating them via serial, similar to the receiver used with the Pi Gateway (or in this case, more similar to RFM69Pi from OEM).
Moteino 2: LoRa radio. Listens to serial packets and repeats them via the radio.
Moteino 3: LoRa radio. Receives packets via LoRa and repeats them via serial. Essentially an RFM2Pi.

I found it easiest to wire the serial connection between Moteino 1 and Moteino 2 by flipping the former belly-up (radio side up). I used right angle headers and some protoboard.

There are three sketches needed.
Moteino 1: Receiver to serial. I used the RFM69Pi firmware sketch and modified the serial baud from 38400 to 115200
Moteino 2: Serial to LoRa. I used the rf95_client example in the RadioHead Examples folder and changed the outbound "Hello World" in the example to the serial input.
Moteino 3: LoRa to Pi. I used the RFM69Pi firmware sketch again, but replaced the JeeLib radio library with the RH library.

Here is the firmware on GitHub, in case they are helpful to anyone.
https://github.com/brandock/Open-Energy-Monitor-LoRa-Bridge

This was a fun project and it works well.
Brandon