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Station
Not
Found
-
This error will occur if the specific
selected station is not detected. This
may mean that the station is off the air or
out of range.
Can't Match Phase Code -
This error occurs if no phase coding
seems to match that of the selected
station. Usually this is because the
master station has been misidentified.
Can't Find Third Zero Cross - This error occurs if the FS700 is unable
to detect the LORAN pulse third zero
crossing.
Tracking Problems
A variety of problems can crop up once the FS700 is locked and
tracking a LORAN station. Most of these conditions are recoverable
without loss of frequency accuracy provided that they do not last too
long. If an antenna, rf, or blink condition occurs, the FS700 will freeze
its FLL so that no erroneous frequency corrections are made. Then,
the FS700 will wait for up to 20 minutes for the condition to go away. If
the condition goes away, the FS700 will restart its FLL and continue
tracking. If the condition does not go away, the FS700 will terminate its
lock and display a timeout error message. If the search mode is set to
AUTO, the FS700 will restart the acquisition process. Otherwise it will
stop. When one of these conditions occurs, the FS700 will turn on the
ERR LED (ANT LED for antenna problems) and display a warning
message. The signal status indicator in the STATUS menu will also be
set. The LED will remain on and the warning message will be displayed
for the duration of the condition and will go off when the condition goes
away. These conditions are fairly common but rarely last long enough
to produce a timeout.
Antenna Warning -
This warning will occur if the current going
to the remote antenna preamp is
abnormally high or low. This may mean
that the antenna has become
disconnected or damaged.
Station Amplitude Fluctuation - This warning occurs when the FS700
detects that the rf signal level has
dropped by more than 10 dB during one
correction period. Long term variations
are ignored.
Station Blinking -
This warning occurs when the FS700
detects that the station being tracked is
blinking its first two pulses.
Noise Margin < 10dB -
This warning occurs if the measured
signal to noise margin of the station
