you need to enter a frequency for park mode, I believe this is used in the cal process,Andrew,
This is not essential. It derived from the time drift was very common. The park frequency was initiated to maintain a more stable generator output, the frequency determined by trial and error.
It may still be used if drift is seen, it might help.
Full details are on the web pages.
Calibration frequency is fixed (around 6MHz?) again full details are published.
73 Alan G4ZFQ