Campbell CRVW3, Инструкция по эксплуатации

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CRVW3 3-Channel Vibrating-Wire Datalogger
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Antenna <--> RF407 <--> RV50 <--> Cell Tower <--> Internet Cloud < -->
LoggerNet computer
Other cell modems could be substituted for the RV50, other Wi-Fi-to-serial
devices for the NL240, and other serial-to-TCP/IP devices for the NL201.
Phone modems could also be used or other telemetry options.
Antenna <--> RF407 <--> Any RS-232-based telemetry option <--> LoggerNet
computer
s.campbellsci.com/documents/us/category-brochures/b_telecommunications.pdf
It is possible to use CRVW3-RF407 at the base station of an RF407 radio
network. This should only be done if a permanent USB cable connection can
be maintained between the base CRVW3 and the LoggerNet computer. It is
expected that this configuration will be used only rarely. The physical
configuration of the base station will have this form:
Antenna <--> CRVW3-RF407 <--> USB cable connection <--> LoggerNet
computer
10.2.8 Plan Validation and Hardware Procurement
Once you have documented your implementation plan for sensors, and planned
out your CRVW3 station sites, repeaters, base station, and LoggerNet computer
station, you should make a field visit to validate radio link feasibility. You
should also get feedback about your plan from others. Slight modifications to
your plan may be necessary. After these activities are complete you should be
ready to place an order to procure your hardware.
10.2.8.1 Pre-procurement Field Visits
It is best to confirm your radio network plan with a visit to the field. One of
your main tasks is to confirm line-of-sight visibility between proposed radio
station locations. Consider using a Radio Test Kit (for example, pn 21107).
This will allow you to work out radio connectivity issues and the types of
antennae needed before procuring hardware. Using the kit, you set up a
temporary radio station at two different sites and measure the connectivity
strength between them. End-node stations use Yagi antennae and repeater
stations (and usually the base station) use Omni antennae. These are also used
as part of the test.
There are several key factors that can influence the quality of a radio
communications link. Some are mentioned here:
Radio Power: Different radio types have different broadcast power options.
The RF451 radio and the CRVW3-RF451 can broadcast at power ratings
configurable up to 1 watt. Practical links can be established at distances of 21
km (13 miles). The RF407 and CRVW3-RF407 operate at a maximum power
of 250 milliwatts, and have a practical range of several miles. In conditions that
are closer to the ideal, longer distance links can be achieved. However, in
certain conditions, much shorter maximum distances occur.
Seasonal Vegetation Changes: Sometimes seasonal changes to the
environment can impact the quality of a radio communications link. For
example, if a radio link is tested in the winter when trees have no leaves, it may