Setting the radiation plane – Raymarine Radar Scanner User Manual
Page 18
10
Pathfinder Radar Scanners
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
D3223-2
Wedge or
washers
Using shims to lower the main beam
D3229-3
Forward
154_4.book Page 10 Wednesday, October 25, 2000 3:02 PM