I was on AliExpress the other day, always an expensive experience, and I happened upon some boards from Heltec that offer an ESP32 (the upgrade of the ESP8266), a tiny OLED display and, most interesting, a connection to the Lora network. I've been meaning to spend some time playing with Lora for a while. It offers low power networking with a range that can go up into kilometres. At first I ordered one, and then it occurred to me that a network with only one node isn't really a network, so I got a couple more.
They arrived on Friday the 13th last week and, much to my surprise given the date, they worked first time. I downloaded the sample programs, added them to my Arduino IDE installation and in no time at all I had two of the devices talking to each other.
Later on I discovered that I have been a little unlucky/stupid in that I've bought versions that work on the 433 MHz radio band, which is not the frequency that works the best for these devices. For the UK I should have bought the version that supports the 868 Mhz band that is used in Europe.
Never mind. I can still use them, but I'll get more interference because this band is used by radio amateurs, car keys and building alarms etc. I'm looking forward to finding out more about how the network can be used.