I'm happy to report that my SB200 is now online between the K3 and KAT 500. Used it this weekend at the Texas QSO Party. Driving the amp with about 35 watts from the K3 gets about 500 watts out, key down. Worked without problems. Thanks for all the comments to my earlier question. 73, Ron, K5HM k5hm.ron at gmail.com www.qrz.com/db/k5hm