On an   Omni six, Ten-Tec they have a tune button which mutes the 
radio when tuning an external antenna tuner.  Great feature.  Is there some 
way of doing the same with the 590 without putting it in C W mode and 
plugging the fones in so you can hear what you need tu hear to adjust the 
tuner?  I know I can do it with a switch but was   hoping there was 
something I am missing.  73  Ed   K7UC