Setting The Radiation Plane - Raymarine Pathfinder Radar Scanner Owner's Handbook Manual

10

Setting the radiation plane

The scanner unit should be mounted so that the array rotates parallel to the
waterline. The radar beam is approximately 25° wide in the vertical direction,
providing good target detection during the vessel's pitching and rolling.
Planing hull vessels, and some displacement hull vessels, adopt a higher bow
angle when the vessel is at its cruising speed. In many cases this substantially
alters and raises the radar's main radiation plane, and can cause poor detection of
nearby targets. It may be helpful to lower the radar beam back towards the
parallel, by shimming the rear of the radar, so that the beam points slightly
downwards with respect to the waterline when the vessel is at rest.
The shims may be made from aluminium plate wedges, simple flat washers, or an
angled wooden block. For thick shims, you may need longer securing bolts than
the M8x40 bolts supplied with the radome scanner, or the M10 studding supplied
with the open array scanners.
12.5˚
12.5˚
Waterline
Ideal Radiation Plane
Wedge or
washers
Forward
Using shims to lower the main beam
Pathfinder Radar Scanners
D3223-2
D3229-3