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BARRETT 4050 HF SDR TRANSCEIVER - OPERATING AND INSTALLATION MANUAL
913 Series Helical Dipoles
(Barrett P/N BC91301 to BC91305)
913 series helical dipole antennas are compact and easily installed, having
extremely narrow bandwidth characteristics and a performance approaching
that of a wire dipole when used at frequencies over 4.5 MHz. The helical dipole
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frequencies.
The 913 helical dipole requires a 50 mm diameter mounting pole. This pole
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any obstruction. Alternatively, the helical dipole can be mounted on top of a
mast or tower. Make sure that the site selected for the antenna is as far from
any source of electrical interference as possible and that under no circum-
stances can come in contact with high tension power lines.
After mounting the helical dipole hub on the mounting pole, remove the front
circular cover, pass the coaxial cable through the hole at the bottom of the
hub. Screw the UHF connector into the balun. Now screw the helical dipole
elements onto the hub. Each element has its frequency marked on the brass
ferrule used to screw the element onto the hub. Assemble the helical dipole
elements in the positions on the hub as indicated by the diagram enclosed in
the hub. Failure to assemble the helical dipole as indicated in this diagram will
cause tuning problems.
Содержание 4050 HF SDR
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