Had some fun with a ping/pong test - use one LoPy on an expansion board via usb, serial in and start up this server code: (sorry, not enough points to upload a file :)
Then the other LoPy connected to notebook with wifi, on a breadboard w/ a single Lion cell - telnet in and enter this client code
Then you can carry the battery LoPy or the notebook around and see what kind of distances you can get in your neighborhood. Idea from radiohead rf95 client/server example.
The full instantiation line is (US frequency):
lora = LoRa(mode=LoRa.LORA,frequency=913100000,tx_power=14,bandwidth=LoRa.BW_125KHZ,sf=10,preamble=8, coding_rate=LoRa.CODING_4_5,power_mode=LoRa.ALWAYS_ON, tx_iq=False, rx_iq=False, adr=False, public=True, tx_retries=1)
No long distance tests yet. Played with some parameters and found these max working distance settings work around the house:
tx_power=20 (US 915 band)
Changing BWto LoRa.BW_125KHZ results in faster data rate and in theory lower receiver sensitivity.
Just found another great write up of LoRa modulation at https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5038744/
This post is deleted!