forum.pistar.uk

Looking at several Simplex and Duplex MMDVM “HS Hat’s” I have here that I’m going to change the TCXO to a higher quality part.
I noticed that ALL my boards (Of all different designs) have the TCXO output going to the OSC1 Pin on the ADF7021, but that pin is for using a 0.8V Clipped Sine TCXO output, OSC2 is for a HCMOS/CMOS TCXO with 3V or higher output and all the published schematics and parts lists all list a part number for a TCXO with a 3V or higher (80% of VDD usually) output.

Just curious to why this has been overlooked? Surely to get the most of a high quality TCXO you would use the correct pin on the ADF7021 and disable the internal OSC.

Does anyone know here where the register R1_DB12 is set high or low, is it in the firmware or MMDVM host and what is it set at by default?

Many thanks.

2W0ODS wrote: ↑Thu May 13, 2021 8:42 am Does anyone know here where the register R1_DB12 is set high or low, is it in the firmware or MMDVM host and what is it set at by default?

Many thanks.

It will be in the firmware, it's available at github

https://github.com/juribeparada

so you should be able to find how that register bit is set by reading the code.