Here's the schematic. I purchased it in 1983. I was wrong he used a 74HC4066 http://elecraft.365791.n2.nabble.com/file/n6898162/scan0014.jpg ----- Jack WA9FVP -- View this message in context: http://elecraft.365791.n2.nabble.com/K3-H-Mode-Mixer-tp6889343p6898162.html Sent from the Elecraft mailing list archive at Nabble.com.