Simrad EY500, Инструкция по эксплуатации

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Calibration
20
P2260/E
The LOBE program will set up "windows" around TS value and Depth. The TS
window is ±4 dB and the Depth window is ±10%. TS samples outside the
windows will be rejected. When starting the calibration, check that the
measured TS value is well within the window. If it is close to the limit, you may,
when moving the sphere, easily end up with TS values outside the window that
will be rejected. To avoid this you should readjust the TS Transducer Gain in
the echo sounder's Transceiver Menu until the reading is closer to the correct
TS value. Then the LOBE program has to be restarted by typing CR/LF and
then F3. This is because the LOBE program has to collect the new settings from
the echo sounder. The Depth window is shown as the green part of the red bar
on the left hand side of the PC display. The present depth of the reference
sphere is shown as the white dot on the right hand side of the bar. Refer to
figure 8.
Then move the reference sphere slowly to collect TS data sets until the file
contains sufficient number (>100) of samples evenly distributed inside the 4
quadrants of the beam pattern. The present or last position of the sphere inside
the beam is shown in white colour (black) and the recorded samples are blue
(grey). The recorded number of Data Sets is shown. When the file is completed,
stop collecting data by typing CR/LF.
If the TS of unwanted objects like fish is recorded, note the sample numbers
when these are recorded. Before processing the recorded data, use an editor to
delete the data recorded from these unwanted echoes. They can be located using
the sample numbers noted, obviously incorrect TS or/and Depth values
appearing incidentally.
When suspect data has been removed, type F4 to check the true transducer
pattern. If this appears to be non-consistent with the expected shape or with
considerable offset values or other anomalies, the possible cause has to be
revealed before the calibration can be completed. The reason may be the
transducer or the transceiver unit.
If acceptable data has been recorded, type F5. The processing of the collected
data will start and the number of iterations is shown at the lower end of the Fit
Menu. When reaching approximately 50 iterations, the processed data will
remain even and the processing can be stopped by typing CR/LF. In the Fit
Menu there is a Relative Angle given in % (
E
in old versions). 150 % means all
accepted samples are being used in the calculation. If the operator would like
to check the beam pattern for a reduced angle, decrease the setting by using the
horizontal arrow keys. Reducing to 100 % the calculation will only use samples
inside the -3 dB circles.