I actually just bought my first meshtastic node and of course it uses LoRa and so I’m now diving into the encoding rates and shit like that. The very long slow seems to use 62 kHz of bandwidth and offers a transverse beat of 0.09kbps. However, you get a link budget of -157dB of decoding on that, which is insane.
Are you actually fully building your own, or are you going to flash, meshtastic? Because apparently, it’s extremely finicky about communication. And if you get one setting different on the modem settings, it won’t talk to anything else except the ones you set up yourself.