[Elecraft] KX3 filter "sweet spot"?

[Thorpe, Jeffrey]

I'm going though the FLDigi manual and have come across (at the "Operating Controls and Displays" section, regarding the QSY button) a reference to the 'sweet spot' and setting parameters for it in the configuration screen. How do you find that? Is that just a 'given' at a particular frequency for the KX3 with the filter option installed?

Jeff - KG7HDZ