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BARRETT 4050 HF SDR TRANSCEIVER - OPERATING AND INSTALLATION MANUAL
Fixed Station Installations
Site Selection Recommendations
The success of every HF Radio system is primarily measured by its ability to
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tant factors need to be considered to achieve success. These include: frequency
selection, time of day and ambient noise at the receiver site. Frequency and
time of day are factors which can be used to calculate the maximum usable fre-
quency (MUF) and lowest usable frequency (LUF), for a particular time of day,
using prediction software freely available on the internet. A typical example of
this is VOACAP, http://www.voacap.com/prediction.html
Site selection and system design go hand in hand and should be considered
before any equipment is purchased. Forcing the radio system into an unsuita-
ble site will undoubtedly result in disappointing if not unworkable performance
of the system. Little can be done to improve an installed system if, for example,
the ambient RF noise is unacceptably high.
It is recommended that site evaluation be done before any system designs are
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The following should be considered when choosing a position for the Trans-
ceiver:
Operating
Convenience
The Transceiver should be placed so that the operator is com-
fortable and any required facilities are easily accessible.
Air Circulation
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dissipate heat generated by the transmitter. The mounting
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Proximity of
Transceiver to
Antenna
When using RG-58 coaxial cable from the Transceiver to the
antenna, a cable length of no more than 30 metres is recom-
mended. Should a run of more than 30 metres be required, it
is recommended that a low loss coax such as RG-213 or RG-8
be used.
It is recommended that the Transceiver chassis is connected
to ground using the bolt on the rear panel to stop pick-up
of unwanted noise from local power supplies and electrical
equipment.
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