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BARRETT 4050 HF SDR TRANSCEIVER - OPERATING AND INSTALLATION MANUAL
914 Series Manual Tap Whip Antenna
(Barrett P/N BC91401 to BC91424)
Installation
914 series manual tapped whip antennas are mounted on vehicles using
a heavy duty base and spring (Barrett P/N BCA91400). The whip should be
mounted on the vehicle in positions such as those illustrated in the diagrams
below. A bracket, fabricated to withstand the forces and vibration that can
be expected during off-road driving, should be used to mount the antenna
base and spring to the vehicle. When locating the mounting position for the
antenna, the ring located above the label at the bottom of the whip should be
level with the surrounding ground plane, e.g. the bonnet of the vehicle or the
roof of the vehicle. Ensure that the mounting bolt on the base and spring is
electrically bonded to the chassis of the vehicle via a very low resistance path,
i.e. clean all joints to bare metal and use braid earth straps if any non-metal
joints are encountered. Use only good quality coaxial cable and water proof
UHF connectors (such as those supplied by Barrett Communications).
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.
When running the coaxial cable from the antenna to the Transceiver, avoid
sharp corners and heat such as that generated by the manifold of the engine.
After installing the antenna check the antenna VSWR on each channel. Gener-
ally if the antenna has been mounted in the positions as illustrated, the VSWR
will be less than 1.6-1 and no adjustment is necessary. If the VSWR is not lower
than 2:1 the antenna to ground capacitance in that installation is probably
outside of the design range of the factory set tuning. Consideration may be
given to retuning the whip if the VSWR is so high as to cause the transmitter
ALC system to begin to reduce power (to protect the transmitter).
Содержание 4050 HF SDR
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