---
logosub: "アマチュア無線家"
language: "jp"
title: "NVIS"
date: "2024-03-09"
---

<div class="alert alert-warning" role="alert">
   <div>
<span>申し訳ありませんが、このページはまだ日本語に翻訳されていません。</span>
   </div>
</div>

<figure class="text-center">
  <picture class="d-flex justify-content-center">
    <source
      media="(max-width: 510px)"
      srcset="/images/radio/antenna/nvis/nvis-setup-diagram-w240.webp"
    />
    <source
      media="(max-width: 850px)"
      srcset="/images/radio/antenna/nvis/nvis-setup-diagram-w480.webp"
    />
    <img
      src="/images/radio/antenna/nvis/nvis-setup-diagram-w800.webp"
      alt="N V I S setup diagram"
      class="img-fluid"
    />
  </picture>
  <figcaption class="figure-caption mt-2">
    <a href="/images/radio/antenna/nvis/nvis-setup-diagram-w800.webp">
      NVIS setup diagram
    </a>
  </figcaption>
</figure>

A [FR-4 PCB](https://en.wikipedia.org/wiki/FR-4) is used. Half of it was scraped off for this design.

<figure class="text-center">
  <picture class="d-flex justify-content-center">
    <source
      media="(max-width: 510px)"
      srcset="/images/radio/antenna/nvis/nvis-pcb-scrape-w240.webp"
    />
    <source
      media="(max-width: 850px)"
      srcset="/images/radio/antenna/nvis/nvis-pcb-scrape-w480.webp"
    />
    <img
      src="/images/radio/antenna/nvis/nvis-pcb-scrape-w800.webp"
      alt="N V I S P C B scrape"
      class="img-fluid"
    />
  </picture>
  <figcaption class="figure-caption mt-2">
    <a href="/images/radio/antenna/nvis/nvis-pcb-scrape-w800.webp">
      NVIS PCB scrape
    </a>
  </figcaption>
</figure>

<figure class="text-center">
  <picture class="d-flex justify-content-center">
    <source
      media="(max-width: 510px)"
      srcset="/images/radio/antenna/nvis/nvis-pcb-w240.webp"
    />
    <source
      media="(max-width: 850px)"
      srcset="/images/radio/antenna/nvis/nvis-pcb-w480.webp"
    />
    <img
      src="/images/radio/antenna/nvis/nvis-pcb-w800.webp"
      alt="N V I S P C B"
      class="img-fluid"
    />
  </picture>
  <figcaption class="figure-caption mt-2">
    <a href="/images/radio/antenna/nvis/nvis-pcb-w800.webp">
      NVIS PCB
    </a>
  </figcaption>
</figure>

<figure class="text-center">
  <picture class="d-flex justify-content-center">
    <source
      media="(max-width: 510px)"
      srcset="/images/radio/antenna/nvis/covering-w240.webp"
    />
    <source
      media="(max-width: 850px)"
      srcset="/images/radio/antenna/nvis/covering-w480.webp"
    />
    <img
      src="/images/radio/antenna/nvis/covering-w800.webp"
      alt="N V I S P C B liquid tape"
      class="img-fluid"
    />
  </picture>
  <figcaption class="figure-caption mt-2">
    <a href="/images/radio/antenna/nvis/covering-w800.webp">
      NVIS PCB liquid tape
    </a>
  </figcaption>
</figure>

<figure class="text-center">
  <picture class="d-flex justify-content-center">
    <source
      media="(max-width: 510px)"
      srcset="/images/radio/antenna/nvis/coax-connector-w240.webp"
    />
    <source
      media="(max-width: 850px)"
      srcset="/images/radio/antenna/nvis/coax-connector-w480.webp"
    />
    <img
      src="/images/radio/antenna/nvis/coax-connector-w800.webp"
      alt="N V I S coax connector"
      class="img-fluid"
    />
  </picture>
  <figcaption class="figure-caption mt-2">
    <a href="/images/radio/antenna/nvis/coax-connector-w800.webp">
      NVIS coax connector
    </a>
  </figcaption>
</figure>

<figure class="text-center">
  <picture class="d-flex justify-content-center">
    <source
      media="(max-width: 510px)"
      srcset="/images/radio/antenna/nvis/nvis-pcb-2-w240.webp"
    />
    <source
      media="(max-width: 850px)"
      srcset="/images/radio/antenna/nvis/nvis-pcb-2-w480.webp"
    />
    <img
      src="/images/radio/antenna/nvis/nvis-pcb-2-w800.webp"
      alt="N V I S P C B"
      class="img-fluid"
    />
  </picture>
  <figcaption class="figure-caption mt-2">
    <a href="/images/radio/antenna/nvis/nvis-pcb-2-w800.webp">
      NVIS PCB
    </a>
  </figcaption>
</figure>

The antenne wires, coiled on a piece of pipe.

<figure class="text-center">
  <picture class="d-flex justify-content-center">
    <source
      media="(max-width: 510px)"
      srcset="/images/radio/antenna/nvis/coils-w240.webp"
    />
    <source
      media="(max-width: 850px)"
      srcset="/images/radio/antenna/nvis/coils-w480.webp"
    />
    <img
      src="/images/radio/antenna/nvis/coils-w800.webp"
      alt="N V I S wire coils"
      class="img-fluid"
    />
  </picture>
  <figcaption class="figure-caption mt-2">
    <a href="/images/radio/antenna/nvis/coils-w800.webp">
      NVIS wire coils
    </a>
  </figcaption>
</figure>

## Diagrams

Some 3d plots of this antenna on 10, 17, 20, 40 and 80 meters made with EZNEC software by PA0ABG. The antenna is most effective on 20, 40 and 80 meters, where the waves go upwards.

<figure class="text-center">
  <picture class="d-flex justify-content-center">
    <source
      media="(max-width: 510px)"
      srcset="/images/radio/antenna/nvis/eznec-10m-28mhz-top-w240.webp"
    />
    <source
      media="(max-width: 850px)"
      srcset="/images/radio/antenna/nvis/eznec-10m-28mhz-top-w480.webp"
    />
    <img
      src="/images/radio/antenna/nvis/eznec-10m-28mhz-top-w800.webp"
      alt="N V I S 10 meter 28 mega hertz diagram boven"
      class="img-fluid"
    />
  </picture>
  <figcaption class="figure-caption mt-2">
    <a href="/images/radio/antenna/nvis/eznec-10m-28mhz-top-w800.webp">
      NVIS 10 meter 28 mega hertz diagram top
    </a>
  </figcaption>
</figure>

<figure class="text-center">
  <picture class="d-flex justify-content-center">
    <source
      media="(max-width: 510px)"
      srcset="/images/radio/antenna/nvis/eznec-10m-28mhz-side-w240.webp"
    />
    <source
      media="(max-width: 850px)"
      srcset="/images/radio/antenna/nvis/eznec-10m-28mhz-side-w480.webp"
    />
    <img
      src="/images/radio/antenna/nvis/eznec-10m-28mhz-side-w800.webp"
      alt="N V I S 10 meter 28 mega hertz diagram side"
      class="img-fluid"
    />
  </picture>
  <figcaption class="figure-caption mt-2">
    <a href="/images/radio/antenna/nvis/eznec-10m-28mhz-side-w800.webp">
      NVIS 10 meter 28 mega hertz diagram side
    </a>
  </figcaption>
</figure>

<figure class="text-center">
  <picture class="d-flex justify-content-center">
    <source
      media="(max-width: 510px)"
      srcset="/images/radio/antenna/nvis/eznec-17m-18mhz-w240.webp"
    />
    <source
      media="(max-width: 850px)"
      srcset="/images/radio/antenna/nvis/eznec-17m-18mhz-w480.webp"
    />
    <img
      src="/images/radio/antenna/nvis/eznec-17m-18mhz-w800.webp"
      alt="N V I S 17 meter 18 mega hertz diagram"
      class="img-fluid"
    />
  </picture>
  <figcaption class="figure-caption mt-2">
    <a href="/images/radio/antenna/nvis/eznec-17m-18mhz-w800.webp">
      NVIS 17 meter 18 mega hertz diagram
    </a>
  </figcaption>
</figure>

<figure class="text-center">
  <picture class="d-flex justify-content-center">
    <source
      media="(max-width: 510px)"
      srcset="/images/radio/antenna/nvis/eznec-20m-14mhz-w240.webp"
    />
    <source
      media="(max-width: 850px)"
      srcset="/images/radio/antenna/nvis/eznec-20m-14mhz-w480.webp"
    />
    <img
      src="/images/radio/antenna/nvis/eznec-20m-14mhz-w800.webp"
      alt="N V I S 20 meter 14 mega hertz diagram"
      class="img-fluid"
    />
  </picture>
  <figcaption class="figure-caption mt-2">
    <a href="/images/radio/antenna/nvis/eznec-20m-14mhz-w800.webp">
      NVIS 20 meter 14 mega hertz diagram
    </a>
  </figcaption>
</figure>

<figure class="text-center">
  <picture class="d-flex justify-content-center">
    <source
      media="(max-width: 510px)"
      srcset="/images/radio/antenna/nvis/eznec-40m-7mhz-w240.webp"
    />
    <source
      media="(max-width: 850px)"
      srcset="/images/radio/antenna/nvis/eznec-40m-7mhz-w480.webp"
    />
    <img
      src="/images/radio/antenna/nvis/eznec-40m-7mhz-w800.webp"
      alt="N V I S 40 meter 7 mega hertz diagram"
      class="img-fluid"
    />
  </picture>
  <figcaption class="figure-caption mt-2">
    <a href="/images/radio/antenna/nvis/eznec-40m-7mhz-w800.webp">
      NVIS 40 meter 7 mega hertz diagram
    </a>
  </figcaption>
</figure>

<figure class="text-center">
  <picture class="d-flex justify-content-center">
    <source
      media="(max-width: 510px)"
      srcset="/images/radio/antenna/nvis/eznec-80m-3.5mhz-w240.webp"
    />
    <source
      media="(max-width: 850px)"
      srcset="/images/radio/antenna/nvis/eznec-80m-3.5mhz-w480.webp"
    />
    <img
      src="/images/radio/antenna/nvis/eznec-80m-3.5mhz-w800.webp"
      alt="N V I S 80 meter 3.5 mega hertz diagram"
      class="img-fluid"
    />
  </picture>
  <figcaption class="figure-caption mt-2">
    <a href="/images/radio/antenna/nvis/eznec-80m-3.5mhz-w800.webp">
      NVIS 80 meter 3.5 mega hertz diagram
    </a>
  </figcaption>
</figure>

The antenna deployed in the field.

<figure class="text-center">
  <picture class="d-flex justify-content-center">
    <source
      media="(max-width: 510px)"
      srcset="/images/radio/antenna/nvis/antenna-nvis-w240.webp"
    />
    <source
      media="(max-width: 850px)"
      srcset="/images/radio/antenna/nvis/antenna-nvis-w480.webp"
    />
    <img
      src="/images/radio/antenna/nvis/antenna-nvis-w800.webp"
      alt="N V I S antenna"
      class="img-fluid"
    />
  </picture>
  <figcaption class="figure-caption mt-2">
    <a href="/images/radio/antenna/nvis/antenna-nvis-w800.webp">
      NVIS antenna
    </a>
  </figcaption>
</figure>
