Specifications for Vertical Antenna

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Breaking down requirements further we get to specifications of each major piece of this antenna system.


We continue our break down of requirements to specifications for each sub-system previously defined.

There are two sub-systems defined: Antenna Ground and Radiator. That's really no surprise for sure. These along with antenna wide requirements brings us to three groups of sub-system requirements ready to be broken down into specifications we can design and build to.

Ground and Radial Specifications

  • Antenna Ground RF resistance shall not exceed 15 ohms.
    • Minimum number of radials shall be sixty (60).
    • Minimum length of radials shall be .4 wavelength at lowest design frequency.
  • Antenna Ground shall be on or under ground level.
    • Radials shall be laid directly on the ground.
    • Radials shall be held to the ground with garden staples.
    • Central radial ground concentrator shall be set into the ground to accept radial wires at ground level.
  • Antenna Ground shall handle 1,000 watts.
    • Radial conductors shall be sized to handle 100 mA at the target RF frequencies.
    • Central ground concentrator shall be sized to handle 5 amps at the target RF frequencies.
  • Antenna Ground shall use ground level conductors.
    • Radial wires shall be insulated.
    • Radials wire insulation shall be black.

Antenna Radiator Specifications

  • Antenna Radiating Conductor shall be configurable for 10 meter band.
    • 10 meter vertical element length shall be quarter wave less end loss tuned for 28.350MHz.
  • Antenna Radiating Conductor shall be configurable for 15 meter band.
    • 15 meter vertical element length shall be quarter wave less end loss tuned for 21.300MHz.
  • Antenna Radiating Conductor shall be configurable for 20 meter band.
    • 20 meter vertical element length shall be quarter wave less end loss tuned for 14.250MHz.
  • Antenna Radiating Conductor may be configurable for 12 meter band.
    • 12 meter vertical element length may be quarter wave less end loss tuned for 24.950MHz.
  • Antenna Radiating Conductor may be configurable for 17 meter band.
    • 12 meter vertical element length may be quarter wave less end loss tuned for 18.200MHz.
  • Antenna Radiating Conductor may have multiple breakpoints.
    • Antenna vertical element shall be composed of conductive plumbing pipe with threaded connections in between.
  • Antenna Radiating Conductor shall be 1/4 wave in physical length.
    • All vertical conductors will be single quarter wave designs.
  • Antenna Radiating Conductor shall be 1/4 wave monopole at each target frequency.
    • Each band will have a unique combination of shorter conductive pieces.
  • Antenna Radiating Conductor shall handle 1,000 watts.
    • Vertical conductor shall be sized to carry 5 amps current at the base.
    • Transmission line feed conductor shall be sized to handle 5 amps.
  • Antenna Radiating Conductor shall have no capacitive and/or inductive traps.
    • Each vertical antenna conductor shall be be a full size single band antenna.
  • Antenna Radiating Conductor shall have no lumped inductances in series.
    • Vertical antenna conductor shall have no capacitive reactance requiring neutralizing with lumped inductance.
  • Antenna Radiating Conductor shall not exceed 17 feet above ground level.
    • The longest vertical antenna radiator conductor shall not exceed 17 feet in length.

Antenna Specifications

  • Antenna System corroding metal parts shall be painted or similarly protected.
    • Paint or shellac shall be applied to any metal parts that oxidize.
  • Antenna System fasteners shall have use anti-seize compound between mating surfaces.
    • Conductive anti-seize paste shall be applied to each radial attachment bolt and nut interface.
    • Conductive anti-seize paste shall be applied to u-bolt mounting hardware.
  • Antenna System feed-point shall accept Coax with PL-259 connector.
    • The central radial plate shall have a SO-238 connector.
    • The central radial plate shall directly connect the shield of the connector to the radial plate.
  • Antenna System shall be located at least 150 feet away from house.
    • Center of antenna shall be located 200 feet from house.
  • Antenna System shall use components and parts from manufacturers.
    • Radial plate shall be the DX Engineering Radial Plate.
    • SO-238 shall be the xxxx
    • The radial wire shall be household insulated wire.
    • Vertical Antenna Conductor shall be copper plumbing pipe.
    • Threaded copper fittings shall attach to sections of copper pipe.
    • Threaded copper fitting will facilitate assembly of vertical antenna into various quarter wave length.
  • Antenna System shall use Stainless Steel where possible.
    • Radial plate shall be made of Stainless Steel
    • Radial wire attaching hardware shall be made of stainless steel.
  • Antenna System should have primary angle of radiation below 45 degrees above horizon.
    • Radial wire length shall be 33 feet long.
  • Antenna System standing wave ratio (SWR) shall not exceed 2:1 at the center frequency of the vertical radiating element.
    • tbd


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