"Knot@Work" wrote in news:ww%0k.2132$Yx.470@trndny08:

Nitro 750
NX

Right next to the display on top of the console would be fine. Many new
units have built-in GPS antennas to make this much easier on everyone. If
you have a bimini top, no problem. The metal frame doesn't obstruct enough
to trash the fix. The only thing to worry about is metal between the
antenna and the sky. As the satellites are in very high orbits giving very
long over-the-horizon times, and are spread across your sky from horizon to
horizon, the most open view of the sky is fine. GPS signal goes right
through a heavy fiberglass top. I'm shooting two GPS antennas on a 41'
ketch from on top of the steering "dash" through a heavy, solid fiberglass
top on an Amel Sharki 41 with great results. The GPS antenna hardly ever
gets wet, even offshore.

You might be interested that the 17 is discontinued, which in marine
electronics lingo means NO SUPPORT. It was replaced by the 717 and I'd buy
that model instead if you insist on this brand/style.
http://www.fishfinder-store.com/huma17.html

God the prices on all manufacturers' units has just become as obscene as
the prices at the fuel dock. Computers are CHEAP....Marine computers are a
ripoff.