I'm working in a project where I have to send data from long distances (about 1 km) between 2 Arduinos UNO which are powered by computer's USB ports. The place is a small city with no large buildings. I have bought two transceptors LORA RA-02 SX1278 at 433 MHz with an antenna for this frequency, like this:

enter image description here

The results are dissapointing. I can reach 300-350 meters with a stable communication (1 data send every 5 seconds). I was only able to, only one time, receive a data from a 1.4 km distance, but the message was corrupt, like this:

enter image description here

I have tried:

  • Different programs and libraries (Now, i'm working with this library)
  • Frequencies from 410 MHz to 525 MHz, according to the range inscriptions on the module

But the distance is still far away from 1 km for a stable communication. I have seen some people reaching 2-3 km with this module and some documents say that it is possible to reach 10 km.

The question is, what am I doing wrong or what I should change to improve the results?

Any help or related experience is very useful!

  • how are the radios powered? – jsotola Jan 19 at 1:16
  • more over with what @jsotola asked, are you sure the voltage is not dropping when it transmits? – Chad G Jan 19 at 5:17
  • 1
    Rather than using that stubby antenna, which is compact but non-directional, you might consider a gain antenna (i.e. a directional one) instead. – jwh20 Jan 19 at 14:54
  • 1
    If you haven't already, you should probably make use of setTxPower. I doubt it will make the difference you're looking for, but it won't hurt. The selectable bandwidth might also have an effect on range. – timemage Jan 19 at 15:36
  • @chad-g The voltage is not dropping, also I have tried with a difference source of power and it works ok. – Agu 1997 Jan 19 at 21:33

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Browse other questions tagged or ask your own question.