b393capt wrote:
MARPA shows vector's and speeds of other boats, that are wrong. After
observing a couple of boats, best I can tell is that MARPA thinks my
boat speed is zero. For example I am catching up to a boat in front of
me, we are both heading east. I expect MARPA shows that boat as heading
east at 5 knots (I am moving at about 7 knots). Instead MARPA shows the
heading of the other boat to me in my direction (270 degrees) at 2
knots, a speed roughly equal to the speed our boats are closing
relative to each other.

It sounds to me like MARPA is working right. All speeds and vectors are
relative you yours.

It may be that it is a MARPA configuration option to display either
apparent speed or speed over ground on targets and that you are
configured to see the latter.

Jack

--
Jack Erbes in Ellsworth, Maine, USA - jackerbes at adelphia dot net
(also receiving email at jacker at midmaine.com)