Service manual

Simrad EK 500 / EY 500
P2260/E 21
In the Fit Menu the rms deviation between calculated beam pattern and the
collected data sets will be given as well as the minimum and maximum
deviation and where these data sets are recorded in the file. The max. and min.
values are shown by a red and a blue cross in the polar diagram. The recorded
max. and min. samples should be removed by using the editor if the deviations
are more than approx. 1 dB. Note the line numbers to locate these unwanted
data. All the remaining data sets are shown in the polar diagram by red and
blue dots. The red ones are those above the calculated beam pattern, the blue
are those below. A cut through the beam can be shown for 0, 45, 90 and 135
degrees by typing F1, F2, F3 or F4. Refer to figure 9.
The final calibration data for TS Gain, Beam and Offset values are calculated
and shown in the Fit Menu. These data should preferably be logged in the
recommended form at the end of this document.
By typing CR/LF one more time, the PC will ask if the operator wants to "Copy
best fit parameters to EK 500 (y/n) ?". When typing y, the calculated data will
be entered into the Transceiver Menu. If the echo sounder is already in the
Transceiver Menu, leave this and enter the same menu again to have the new
settings displayed.
When the reference sphere is located in the centre of the beam after the
calibration has been completed, the TS value in this position may be a little
higher than the correct TS. This is more perceptible using old versions of the
LOBE program with a little bit different algorithm.