- Barrett P/N’s 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 antenna is fed by a single coaxial
feeder and can accommodate up to 5 frequencies.
The 913 helical dipole requires a 50mm diameter mounting pole. This pole should be long
enough to place the helical dipole at least 5 metres above 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 circumstances it 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.
913 series helical dipoles
3 frequency helical dipole
BARRETT 950 HF TRANSCEIVER
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