User's Manual

Synapsis Radar
with Nautoscan NX Pedestal
Operator Manual
Edition July 2015
3-11
4265.DOC020102
It often appears that the radio wave propagation is abnormal (duct effect), when
the object is a very large mountain. If the signal reception level, however, is
small and the transmitted pulse intervals are slightly changed, then a long
cloudy form echo appears as shown in the figure, and can easily be identified.
If it is difficult to identify, reduce the receiver gain (GAIN) slightly. In rare cases,
the guard ring alarm goes off. In this case, check and observe the video
echoes, and reduce the receiver gain, and in case of medium range scale (3, 6,
12 Nm) switch to LONG PULSE or to 24 Nm range scale (Figure 3-9).
Figure 3-8 Second Trace False Echo, Duct Effect
Second trace false echo
Radar range
Out of range
Second trace false echo
Second trace false echo
Atmosphere