
THE RADAR SYSTEM - OPERATIONAL CONTROLS
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Section 10.2) which require that the means provided
for obtaining bearing should enable the bearing of a
target whose echo appears at the
edge
of the display to be
measured with an accuracy of ± 1° or better. It is essen-
tial to appreciate that the permitted error of ± 1° refers
only to the measurement of the angle and does not take
into account other sources of bearing errors. The
inherent accuracy of radar bearings is discussed, and the
procedures for ensuring that the potential accuracy is
realized are summarized, in Section 6.9.9.
6.9.4 Parallel index
This comprises a pattern of equally space