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StuartsProjects / SX12XX-LoRa

Library for SX12XX LoRa devices
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The modulation settings for the SX1268 chip do not work correctly - E22-400M30s #79

Closed piotrret closed 6 months ago

piotrret commented 6 months ago

Hello, first of all I would like to say that the library you wrote is very cool and extremely helpful. I only encountered one small problem. I use the Ebyte E22-400m30s module and I did tests using the code from the example https://github.com/StuartsProjects/SX12XX-LoRa/blob/master/examples/SX126x_examples/Basics/58_FM_Tone/58_FM_Tone.ino The code contains parameter deviation = 10000, but no matter what value I set, it does not affect the modulation depth of the FM signal. In addition, the output signal is terribly distorted and contains a lot of harmonics. Previously, I tested with the Ra-02 module containing the SX1278 chip and the FM signal was generated correctly - I could change the modulation in the program. For the SX1278 module I used an example https://github.com/StuartsProjects/SX12XX-LoRa/blob/master/examples/SX127x_examples/Basics/58_FM_Tone/58_FM_Tone.ino that is very similar.

StuartsProjects commented 6 months ago

The generation of a FM tone is a bit of a fudge, the carrier is rapidly switched in frequency. The tone examples do work on the supported SX1262 and SX1268 modules.

I have never tested the Ebyte E22-400m30 modules, since I dont have one. That module has a RF power amplifier added and its possible that it is reacting badly to the rapid frequency shifts. I cannot think of a solution to such a problem.

StuartsProjects commented 6 months ago

No support for the Tone functions on modules that have a RF PA added.