Meshtatic and MeshCore - NOT amateur radio

Some people look for ways to communicate that do not depend on the internet. I have no experience of these which use licence free Lora to join up stations without the internet. 

In theory, if the network is big enough almost anyone should be able to message anyone. I have no idea how large these meshes are.

The aim is to have nationwide (or even international) networks that allow text messages to be exchanged in public or as a private message without the internet.  

It looks like apps are available for Android or iOS phones.

There is a map of Meshtatic nodes.

LORA DX

On Amateur Radio Weekly yesterday was a small yagi to extend the range of LORA systems. They were claiming a range of 40km, although I expect that was line-of-sight. LORA is a long range, licence free, data system using spread spread spectrum techniques.

See https://en.wikipedia.org/wiki/LoRa .

LoRa

LoRa modules are available from Amazon and I expect quite a few other sources. To my knowledge, two people locally have experimented with 868 MHz LoRa modules. I am not sure if this was for commercial reasons or just for fun. 

As far as I know, anyone  may use the licence free ISM bands (certainly in the UK) as long as the interface conditions are met. This often means low power and the acceptance of interference. At 868 MHz there are some odd duty cycle limits I think.

If you do not have an amateur radio licence, this may be a route to experiment.

LoRa devices at 863-870 MHz

 As far as I can gather, this band is licence exempt in the UK and may be of use to experimenters. I have not read the regulations wrt ERP etc.. 

It may be of use for short-range experiments over a few kilometers. I expect there are several RF modules available.