On Feb 21, 9:32 am, john smith wrote:
In article . com,

The advantage of having the NAV frequencies is that you can duplex with
AFSS over a VOR. The radio can be set to listen on the VOR frequency and
transmit on the COM frequency when the PTT is depressed.
The NAV function does not work well because of the antenna polarization.
NAV frequencies are horizontal, COM frequencies are vertical.

That is true. It was a handy feature 20 yrs. ago, but the
proliferation of RCOs, even out here in the west, means that it's a
pretty rare occasion that you actually have to talk to and FSS over a
VOR. I haven't done it in years. YMMV.

Antenna polarization is the key to nav performance on the
handheld. I once hooked mine up to the horizontal nav antenna
instead of the vertical com antenna. Nav performance was rock solid,
but my com performance suffered quite a bit.

John Galban=====N4BQ (PA28-180)