I program the mini boards using an usb to ttl converter, and keep it connected for the receiver to have serial monitor, the LoRa is connected to the voltage regulator, the GND connection is soldered between the mini boards and the LoRa modules.
By GND you mean the GND from the output of the 3.3v regulator connected to the GND of the input of the regulator where the board and the battery are connected?
make a common ground connection otherwise you can get corrupt data
connect the ground of the Pro Mino to the ground to the RA-02 to the ground of the power supply
By default, not sure I understand why, that library appears to accept received packets that are corrupt, packet CRC checking is off.
The LoRa modules have built in CRC checking which works very well, not sure why you would want to leave it off.
However, not quite sure why there is so much corrupt data in the first place, I have operated TX and RX LoRa modules together on the bench on a great many ocaisions, corrupt packets do not happen very often.
Maybe corrupt packets can be expected on weak signals, but RSSIs in the -50dBm region would normally provide a very large number of valid packets.
I soldered all the GND togheter, but now I do not receive anything like last time, it just says LoRa Receiver...
Should I use another library?
I tried to change the TX and RX between them, program the RX as TX and the TX as RX, still the same happens not receiving anything....
Thats a very well established library, used by lots of people, so you would assume its good.
Are you using directional antennas on both devices?
Check your wiring and soldering carefully to make sure everything is good. Look for solder blobs shorting multiple pins together.
Bit of a mystery really.
The RSSI reported indicates strong signals, which would normally mean almost error free. I have had UHF LoRa TX and RX modules running on the bench on a great many ocaisions, error rates in the 1% region are normal.
You could try them a bit further apart, 20m or so.
Or enable CRC on both TX and RX;
LoRa.enableCrc();
And that should reject the corrupt packets.
One possibility is that one LoRa module is slightly off frequency, and if that were the case increasing the bandwidth to 500khz would improve reception.
could there be a 433MHz device in the area transmitting and corrupting the LoRa transmissions?
when I have been experimenting with 433MHz modules sometimes the fire alarm was triggered and car key fobs failed to operate
never had major problems with LoRa communication though - only missing the odd packet
So I know a lot of time passed, apparently the problem was caused by the antennas, after I changed them for TRUE 433mhz ones, my modules now work, thank you again for your support!
mark your post 32 as the solution to help anyone else with the same problem