Posted by ANDY DURBIN on Jun 22, 2018; 3:35pm URL: http://elecraft.85.s1.nabble.com/KPA-1500-ATU-not-working-well-tp7642239p7642252.html
"It might be but the amp is designed to work with radios other than K3s."
The KPA1500 and KPA500 are both capable of receiving frequency from transceivers other than the K3S, so is the KAT500. I don't see how not using a K3S puts any limitation on my proposal.