Datawell 45100, Руководство пользователя

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4.1.1 GPS position
When the buoy being received is equipped with a GPS module, the GPS position of the buoy is
shown on the display. The GPS position message is “rotated” with the heave message according
to the scheme shown in figure 4.2.
Figure 4.2. Heave message and GPS message rotating scheme.
Note that the update rate of the GPS position is defined by the received buoy. Please refer to the
buoy documentation for more information.
4.1.2 Signal quality
When displaying heave, a signal quality bar graph is shown on the display, see figure 4.2. The
signal quality indication is derived from the “frame error rate” (FER) parameter. A full-scale
deflection of this bar indicates that no errors are detected in the incoming vectors (FER = 0%)
while no deflection at all indicates that all vectors contain errors (FER = 100%).
4.1.3 Speaker
The speaker is used to get an audible indication of the signal quality. A 1500 Hz frequency-
modulated beat-note should be heard against a clean background (none or clean noise without
any sign of interference or noise bursts).
The speaker can be switched on and off by pressing the button.
4.2 Checking the receiver alignment
The RX-D2 has a built-in test mode that is used to check the receiver alignment. The test mode
is entered by holding the button down for more than 3 seconds. The test mode is exited by
pressing the button again.
Figure 4.3. test mode
During test mode, the receiver alignment is shown in the form of a bar graph, see figure 4.3. The
bar graph reading is only valid when the buoy signal is being heard through the speaker. If the
RX-D2 is not receiving any signal, the bar graph reading is not valid.
When the receiver alignment is within the operating range the bar graph will show the
alignment as shown in figure 4.3. When the receiver alignment is not within the operating range,
the message “
out of range
“ is shown. If this is the case and the signal quality is poor then