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minimal parts wspr tracker with SI5315 but without his own TCXO

I did find out that the ATGM336h does carry an onboard TCXO at 16.369 MHz. This is an 0.5 ppm version. 

It is possible to remove the tin cap from the GPS and wire the SI5351 input by 100 nF (SMD) capacitor to the TCXO output, saving the separate TCXO for the radiochip and get even better stability as with the common 1 ppm 25 - 27 MHz TCXO's

This way it's possible to make a tracker with 3 active parts:

Atmega328p, SI5351, GPS module, and 4 passive parts, Resonator 4 MHz, series capacitor for TCXO to SI5351 and 2 capacitors 100nF and 1 uF for decoupling the DC 3.3 Volt

Don't forget to change the SI5351 setting to 16.3690000 MHz reference source.