+ AA6YQ comments below

This version corrects the Filter problem with the K4, Thanks!

+ Thanks for the testing and report, Gordon.

The $ symbol in K4 commands is for the second receiver, so IS is main receiver, IS$ is sub receiver, I forgot to point that out. That applies to all commands that affect a receiver.

+ So the incorrect behavior was caused by Elecraft changing the function of the K4's IS command (in comparison with the K3 IS command) to convey one tenth of the desired shift rather than the exact desired shift ( and not 10x the desired shift , as erroneously specified in the documentation).

73,

Dave, AA6YQ