I feel that the idea of an NVIS antenna is very simple, yet it seems people are still confused about it. It’s as simple as a wire dipole antenna at 1/4 to 1/8 of a wavelength off the ground.
Also, I’ve had some people try telling me you can use higher frequencies for NVIS. You can try higher frequencies, but EVERYTHING that is written in every book, even military manuals says NVIS works on 80-40 and sometimes up to 20 but not often. They even have a website dedicated to measuring the critical frequency daily so you can check how high you can go that day. Here is that site
There are also people on the internet saying they are getting NVIS propagation with a 40m Hustler vertical. I have tested this, and it is definitely not getting true NVIS propagation. It would make random contacts in the NVIS range, but it is NOT getting over the mountain NVIS propagation like a horizontal antenna does. Video below:
To get the best idea of how NVIS propagation works for you, you should get out and test, test, test!! You can read all the blogs and watch all the videos you want, but nothing compares to getting out and putting theory into action. See you on the air.
Wyoming Survival 