[Elecraft] KX3 query

[W4ISH]

I have the KX3 and the KPA500 and KAT500 (just sold the K3 and saving for the K3S) and I was wondering if it is possible to connect the KX3 Serial line through either the KAT500 or the KPA500 so that they could read the frequency and automatically switch to the correct band/preset tune as the frequency of the KX3 is varied.  I realize that a short “dit” or two will allow it to make the switchover, but I would like to do it without having to send the “dit”

Bill