I use a Band Decoder Card from Unified Microsystems to drive my antenna relais. http://www.unifiedmicro.com/decoder.html 73 de Jan SM5FQQ ----- Elecraft K3 #2054, Butternut HF9V -- View this message in context: http://elecraft.365791.n2.nabble.com/K-Line-Antenna-switching-tp7563906p7563926.html Sent from the Elecraft mailing list archive at Nabble.com.