These elevated feed-point monopole antennas have been designed for HF receiving applications as either a standalone element or as an element in an array.
Each antenna operates from 1.5 to 30 MHz. For enhanced performance, models EFM-6,12 or 18 can be used together to provide separate low, mid, and high band receiving elements.
The antenna consists of a rugged stainless-steel radiator having a solid insulator fitted at the feed point that is located above the base of the antenna. An impedance transformer/matching network provides suitable impedance transformation to a 50-ohm coaxial cable input. The position of the feed-point combined with the transformer impedance ratio allows optimum performance over a selected operating bandwidth.
The antenna is mechanically stabilized by non-conductive guy wires.
A radial earth mat of any length, consisting of up to 64 copper wires can be fitted to the base of the antenna to stabilise antenna impedance and radiation patterns.
FEATURES / BENEFITS
Rugged, high-reliability construction with stable performance
Proven design, installed in multiple locations over many decades
Stainless steel construction for harsh environments
Cyclonic wind rating
Element performance can be optimized for specific operational requirements, frequency sub-bands, or array configurations using RFS state of the art simulation and optimization algorithms
Hinged base construction allows ease of maintenance and installation
1.5 - 32
Optimum Frequency Range
Elevation Radiation Pattern
Refer to plot
Azimuth Radiation Pattern
Maximum Power Rating
Typical <3dB from 4 MHz to 10 MHz
Typical <2.5dB from 7 MHz to 18 MHz
Typical <2.5dB from 15 MHz to 32 MHz
Mismatch Loss Note
Mismatch loss/bandwidth properties can be adjusted to suit customer operational requirements
Impedance (unbalanced), ohms
Wind Survival Rating (no ice)
Operating Temperature Range
-20 to 70 (-4 to 158)
Material - Guys
Phillystran or equivalent (option: Insulated Stainless Steel)
Material - Radiators
Stainless Steel Tube
Material - Earth Mat
Up to 64 copper radials, or mesh ground screen when used in array configuration