Chameleon Antenna CHA MPAS, Руководство оператора

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CHA MPAS Page 7
The Antenna Connection is located on the top of the Hybrid Micro Base (a). It is a 3/8” x 24 (fine thread)
female fitting.
i. Counterpoise Connection
The Counterpoise Connection is located on the bottom of the Hybrid Micro Base (a). It is a 3/8” x 24 (fine
thread) male fitting.
j. Antenna Shackle
The Antenna Shackle assembly, see plate (3), consists of a shackle, bolt, and nut. It is attached to the top of
the Hybrid Micro Base (a).
Antenna Configurations
Using the supplied components, the CHA MPAS can be deployed into a number of configurations. Seven
configurations
(some configurations require optional components that are sold separately) , see table (2), are
described in this manual, each with unique performance characteristics.
Configuration Ground Short Medium Long Directionality
Manpack Vertical ↕ Omnidirectional
Portable Vertical ↕ ↑ Omnidirectional
Horizontal NVIS ↓ ↑ Omnidirectional
Sloping Wire ↓ ↕ Unidirectional
Inverted “V” ↓ ↕ ↑ Bidirectional
Inverted “L” ↓ ↕ Unidirectional
Tilted NVIS ↓ Omnidirectional
Table 2. Antenna Configuration Selection.
The table can assist the operator to quickly select the most appropriate antenna configuration to meet their
operational requirements. To use the table, decide which distance column (Ground = 0 to 90 miles, Short = 0 - 300
miles, Medium = 300 – 1500 miles, Long > 1500 miles) best matches the distance to the station with whom you
need to communicate. Then, determine if the OWF is in the lower (↓ = 1.8 – 10 MHz) or upper (↑ = 10 – 30 MHz)
frequency range. Finally, select the antenna configuration with the corresponding symbol in the appropriate
distance column. All CHA MPAS configurations provide some capability in each distance category, so depending
upon the complexity of your communications network, you may need to select the best overall configuration. The
directionality column indicates the directionality characteristic of the antenna configuration. When using NVIS, all
the configurations are omnidirectional. Most configuration and frequency combinations will require a wide range
antenna tuner or coupler.
Manpack Vertical
The CHA MPAS Manpack Vertical configuration, see figure (1), is a broadband short range HF/VHF-LO antenna.
This configuration, which is especially designed to be manpackable, is omnidirectional and provides ground wave
communication on frequencies between 1.8 – 54.0 MHz without using sky wave propagation. Performance is
limited below 3.5 MHz, but very good above 24 MHz. A single 25 foot counterpoise “tail wire” will provide a good
compromise between portability and performance or you can use the supplied 60 foot antenna wire as the