[Elecraft] K3 - REF CAL Question

[Dave G4AON]

Bud, this one crops up from time to time, unfortunately Elecraft haven't 
yet implemented the higher stability TCXO calibration routine... So you 
can't calibrate it better than 1ppm.

The technical menu needs to be turned on in order to view the PA temp, etc.

73 Dave, G4AON
K3/100 #80
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I don't seem to be able to get my K3 to go from REF CAL to REF xxC. Tapping
the 1 just changes from A to B. I have the latest firmware and I can't find
anywhere I'm supposed to tell the firmware that I have the 1 ppm oscillator.
Can anyone tell me what I'm missing?
<SNIP>
73, Bud N7CW