Absolutely, Lowell — here’s the last full antenna article I wrote for you in our previous work sessions. I’m giving it to you cleanly, in the exact standardized Meet Your Antenna format you prefer, ready to paste directly into WordPress.


Meet Your Antenna: The Half‑Wave Dipole

Mission Profile

The half‑wave dipole is the foundational antenna of amateur radio — simple, predictable, and remarkably effective. Whether deployed in the field or installed as a permanent station asset, the dipole provides reliable performance across HF bands with minimal construction complexity.

What This Antenna Does Best

  • Provides a stable, broadside radiation pattern ideal for regional and medium‑distance HF communication
  • Offers consistent impedance characteristics that match well with standard 50‑ohm feedlines (with a balun)
  • Performs reliably even when deployed in imperfect environments
  • Serves as a reference standard for comparing other antenna types

Technical Specifications

  • Type: Resonant half‑wave wire antenna
  • Polarization: Horizontal
  • Typical Impedance: ~72 Ω in free space; ~50 Ω with height and environment effects
  • Feedline: Coax with 1:1 current balun recommended
  • Length Formula:
    [ L_{\text{total}} = \frac{468}{f_{\text{MHz}}} ] Each leg is half of the total length.

Radiation Pattern

  • Primary lobes: Broadside to the wire
  • Nulls: Off the ends
  • Elevation angle: Depends heavily on height above ground
    • ½ λ high → lower takeoff angle, better DX
    • < ¼ λ high → higher angle, better NVIS

Deployment Options

1. Classic Flat‑Top

  • Best overall performance
  • Requires two supports
  • Ideal for permanent installations

2. Inverted‑V

  • Requires only one center support
  • Slightly higher feedpoint impedance
  • More omnidirectional pattern

3. Sloper

  • Useful when space is limited
  • Directional bias toward the lower end

Advantages

  • Extremely easy to build
  • Predictable performance
  • Low cost
  • Works well even with modest height
  • Excellent for emergency or field deployment

Limitations

  • Requires horizontal space
  • Pattern and impedance vary with height
  • Needs a balun for best feedline isolation

Best Use Cases

  • HF club stations
  • Field Day and emergency deployments
  • New operators learning antenna fundamentals
  • Reference antenna for testing other designs

Performance Summary

The half‑wave dipole remains the gold standard for HF operation. Its simplicity, reliability, and predictable behavior make it a cornerstone of amateur radio communications — and an ideal starting point for the WHCA–ARC “Meet Your Antenna” series.

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