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being tracked drops to less than 10 dB.
A different station should be chosen if
possible.
Noise Margin < 1dB -
This error occurs if the measured signal
to noise ratio of the station being tracked
drops to less than 1 dB. In this case,
tracking is terminated. The FS700 does
not wait for the error to go away.
Oscillator near end of Tuning Range - This warning occurs if the internal
oscillator is at 75% of full scale to warn
the operator that the oscillator needs to
be adjusted. This warning should rarely
occur, if at all, and is easily corrected by
adjusting the oscillator's coarse
frequency adjustment screw (see
TROUBLESHOOTING section of
manual).
Oscillator Tuning Range Exceeded - This error occurs if the internal
oscillator is at the end of its electronic
tuning range. In this case the lock is
terminated. This error should rarely
occur, if at all, and is easily corrected by
adjusting the oscillator's coarse
frequency adjustment screw (see
TROUBLESHOOTING section of
manual). This error can also occur if the
FS700 accidentally tries to lock to
something that is not a LORAN station.
In this case, restarting the lock will solve
the problem.
Excessive Phase Shift -
This error occurs if the FS700 detects a
sudden, large (>120 degree) phase shift
of the LORAN signal relative to the
FS700's internal oscillator. In this case
the lock is terminated. This error can
occur when a LORAN station makes a
rare timing error.
Frequency Generation and Calibration
The FS700 has a built-in frequency source and phasemeter. These may
be used to generate precise frequencies and to calibrate external
frequency sources. The frequency source may be set to output
frequencies between 0.01 Hz and 10 MHz. The phasemeter can
measure phase differences for input frequencies between 100 kHz and
10 MHz.
