ICS Nav6plus, Руководство пользователя

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NAV6 plus NAVTEX System User Guide
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The bar graph is a visual guide to reception quality.
When reception quality is good, the reported error rate will be low ( <4%
). Note that the bar graphs give a visual indication of the error rate and
an indication of the trend (increasing or decreasing error rate). The error
rate is calculated as an average over a large number of received
characters.
Note that once a transmission stops and the transmitter shuts down, any
error rate that was previously displayed will slowly return back to 0%.
Evaluating a proposed sensor location
Evaluating a proposed sensor location Evaluating a proposed sensor location
Evaluating a proposed sensor location
A methodical approach when evaluating a proposed sensor site would
be to note down the average error rate from each station.
Then make a change to the proposed sensor location, take a new set of
% error readings and consider your options.
Ideally you need to receive from at lest one distant station that is 100
miles or more away or you may find it impossible to get any received
error count at all.
As most NAVTEX stations just transmit for a maximum of ten minutes at
a time in every four hours, you will have to work quickly.
Alternatively, take your time and make a new set of readings after four
hours has elapsed.
Fine tuning the sensor installation
Fine tuning the sensor installation Fine tuning the sensor installation
Fine tuning the sensor installation
If you want to increase the sensitivity of your system and hence the
range of reception, you can try connecting the screen of the sensor
interconnecting cable from the connecting block direct to a good
electrical ground. This can either be a specially installed ground plate, or
the keel bolts on a non-encapsulated keel.
Refer to Sensor installation section for full details of recommended
grounding arrangements.
Take careful note of reception error rates on the NAVTEX monitor page
both before and after attaching a ground connection. Note that
connection to an inappropriate or electrically noisy ground point can