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The venerable Inverted-L is the most popular antenna for the low bands, due in large part to its simplicity. It has enabled many hams to get on 80, 160, or even lower from their city lots. Unfortunately, its ease-of-use has allowed substantial misunderstandings as to design theory.

This article will address several of the most oft-repeated myths regarding Inverted-L’s for the low bands. In a future follow-up article, I will detail the construction of a 160m Inverted-L at my new QTH using the “Ten Commandments” provided below.

Myths and Realities:

Ten Commandments for your Inverted-L

By way of summary, here are my basic design requirements for a good Inverted-L. Many of us, myself included, can’t have all of them, but we should attempt ​most ​ of them. After all, who among us is without sin?

  1. Don’t use SWR as a design metric
  2. Make the vertical section as tall as possible
  3. Use as many evenly-spaced radials as possible
  4. Use a decent choke at the feedpoint
  5. Avoid lossy bottom-loading
  6. Place the vertical element in the open, away from trees and buildings if possible
  7. Use high quality coax or hardline to feed the antenna
  8. Match at the feedpoint, only use a tuner in the shack as a last resort
  9. Use empirical performance tests; avoid “I snagged 3Y0 so it works fine” -statements
  10. Don’t use SWR as a design metric (again)