g4klx / MMDVM

The firmware for the MMDVM (Multi-Mode Digital Voice Modem)
GNU General Public License v2.0
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RF7021 and 14.7456MHz TCXO in Config.h #344

Open klaute opened 8 months ago

klaute commented 8 months ago

Hello,

a few years ago I bought a RF7021SE board to build my own MMDVM host. I never had the time during the last 7 years so I would like to startover now.

Also I have a STM32F103(C8T6) board.

I followed the tutorial from F5UII: https://www.f5uii.net/en/hotspot-homebrew-zumspot-mmdvm-pistar-tune/amp/

This documentation explained that I need to replace the TCXO by a 14.7456MHz version which has +-2.5ppm accuracy.

Is this firmware also compatible to my hardware? In the configuration file of the MMDVM firmware starting from line 60 this is not a possible option, only 14.4MHz is available:

https://github.com/g4klx/MMDVM/blob/master/Config.h

My question is now, what do I need to configure here? Or is it possible to use a different TCXO on my RF7021 transceiver board?

Anyways the TCXO is not easily available in Germany, until you want to pay around 25€ for three pieces.

Thank you!

Kai