Well, to be technical, the sensitivity of an ht compared with a mobile is 
about the same.  I know, I have a service monitor.  The big problem is 
filtering and rejection.  Even today's mobiles are not as good as the old 
rigs use to be, but they're made to receive from aircraft clear up to 
172--front end as broad as a barn door.  We bought a special filter for 
our club repeater, less than a db loss on xmit and receive, covered 144 to 
146, but it wasn't cheap, around a hundred bucks.  AS I said before, my 
t90 is absolutely useless on an outside antenna.  The Kenwood f6 is very 
good.  Not sure what the difference is.
73s
Butch Bussen
wa0vjr