"Roger Gt" wrote in message
. com...
I have five on my 26 foot sail boat. Marine VHF on the stern, Amateur on
the port spreader, TV on the starboard spreader, A scanner and a GPS on the
mast head.

Why would one mount a gps antenna on the masthead? Wouldn't the normal roll
of the boat cause that antenna to travel several feet and cause the position to
change
on each cycle? I would think rail or arch mounted would be more stable. Ours is
mounted
in the overhead of the pilot house in the opening for the sliding hatch, which
is lexan.

Leanne
S/V Fundy