SESKStuff Everyone Should Know
SESK: Stuff Everyone Should Know · sesk.info/ham-elliptical-polarization

Ionospheric signals are elliptically polarized. What does that mean for your antenna choice?

Vertical or horizontal antennas can both send and receive.

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  1. Both antennas must have the same polarization
  2. Vertical or horizontal antennas can both send and receive ✔
  3. Digital modes become unusable

Why: After a trip through the ionosphere, a signal's polarization gets mixed up. So for skywave contacts, a vertical or a horizontal antenna will work.

Huh, didn't know that: Polarization matters much more on direct VHF and UHF paths than on ionospheric skip.

The dad joke
My antenna is horizontal and my friend's is vertical. Thanks to the ionosphere, we still get along.
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References

Answer: Vertical or horizontal antennas can both send and receive. After a trip through the ionosphere, a signal's polarization gets mixed up. So for skywave contacts, a vertical or a horizontal antenna will work.

  1. 2026-2030 Technician Class Question Pool, T3A09 ncvec.org/downloads/2026-2030%20Technician%20Pool%20and%20Syllabus%20Public%20Release%20Feb%2019%202026.pdf
    Either vertically or horizontally polarized antennas may be used for transmission or reception
    Checked 2026-10-09.

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