Encouraging results with the QRP Labs' QMX's GPS-disciplined Virtual U3S WSPR transmissions.

These 60m WSPR spots at the GPS-disciplined KFS receive site (172 km) yielded ~57 milliHertz, that is, 0.057 Hz average stability.
That is steady enough to see the ionosphere's ~2 Hz Doppler shift when its height changes at dawn (1400 UTC) and at dusk (0130 UTC).
The SNR trace also shows signal fading in response to the geomagnetic storm around 10/10 1800 UTC.  

Radio: QMX+ with firmware 1_04_010 & QLG3 GPS Module.
Frequency 5.366160 MHz, Power 1 watt, Calibration time 30s.

73, Carol KP4MD
Citrus Heights, CA

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