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alexander-sholohov / si5351-beacon

WSPR beacon based on Arduino + si5351
MIT License
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SI5351 with 25 MHz Xtal #2

Open sp2ong opened 5 years ago

sp2ong commented 5 years ago

Hi Alex,

Because I have use SI5351 https://learn.adafruit.com/adafruit-si5351-clock-generator-breakout/overview with 25 MHz Xtal I found in your source definition of XTAL in si5351-beacon/src/utils/jt_band_params.cpp #define XTAL_FREQUENCY_IN_KHZ (27000) after correct this value to 25000. But found other file si5351-beacon/src/si5351/radio/register_map.h and I am not sure that I need have other values for 25 Mhz Xtal SI5351 ???

alexander-sholohov commented 5 years ago

Hello, None of them defines output frequency. Only XTAL (Hz) parameter from online configurator defines it actually. link to online configurator. Parameter in jt_band_params.cpp (XTAL_FREQUENCY_IN_KHZ ) - is using in band reconstruction algorithm. It selects proper LPF from given parameters. It is not very critical. register_map.h - autogenerated file from Silabs software. It is possible to configure all three outputs of si5351 to produce some frequencies from the beginning . It is not critical at all. I've never tried that.