Setting - up the radar involved orientating it in a known azimuth ( the basic mounting could cover an arc of 4800 mils ) and setting the datum beam elevation between - 90 and 360 mils .
Datum beam elevation was above the radar horizon .
Setting - up the radar involved orientating it in a known azimuth ( the basic mounting could cover an arc of 4800 mils ) and setting the datum beam elevation between - 90 and 360 mils so that it was above the radar horizon .