NVIS antenna
============

This [Near vertical incidence skywave antenna](https://en.wikipedia.org/wiki/Near_vertical_incidence_skywave) was made for me by PA0ABG.

![N V I S setup diagram](/images/radio/antenna/nvis/nvis-setup-diagram)

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

![N V I S P C B scrape](/images/radio/antenna/nvis/nvis-pcb-scrape)

![N V I S P C B](/images/radio/antenna/nvis/nvis-pcb)

![N V I S P C B liquid tape](/images/radio/antenna/nvis/covering)

![N V I S coax connector](/images/radio/antenna/nvis/coax-connector)

![N V I S P C B](/images/radio/antenna/nvis/nvis-pcb-2)

The antenne wires, coiled on a piece of pipe.

![N V I S wire coils](/images/radio/antenna/nvis/coils)

## 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.

![N V I S 10 meter 28 mega hertz diagram top](/images/radio/antenna/nvis/eznec-10m-28mhz-top)

![N V I S 10 meter 28 mega hertz diagram side](/images/radio/antenna/nvis/eznec-10m-28mhz-side)

![N V I S 17 meter 18 mega hertz diagram](/images/radio/antenna/nvis/eznec-17m-18mhz)

![N V I S 20 meter 14 mega hertz diagram](/images/radio/antenna/nvis/eznec-20m-14mhz)

![N V I S 40 meter 7 mega hertz diagram](/images/radio/antenna/nvis/eznec-40m-7mhz)

![N V I S 80 meter 3.5 mega hertz diagram](/images/radio/antenna/nvis/eznec-80m-3.5mhz)

The antenna deployed in the field.

![N V I S antenna](/images/radio/velddagen/2023-12-30/wwff-2023-12-30-antenna)
