PH probe calibration PII v5.17

Hi,
I need to re-calibrate a ph probe as I bought a new one, however there is no "calibration" setting in firmware 5.17 for any probe other than temperature?
If I go to the menu on the unit itself there is no "calibration" in PH settings.. What do I do?
Many thanks!
Pat

I have changed settings in the "Signal Filter" in PH menu to value "1 - Strong" and now the calibration menu appered. Means that the unit did not recognize the probe :) Just for everyone else's information!
Pat