My first trip into the local ham radio store was made with one question in mind; what do I need to do to listen to lots of stuff, and talk locally for 0-200 miles(ish); similar to what we did with radios in the Army. The person I was talking to looked quite confused at my question and thus began my quest.
Now that I have enough comfort with the science, skill, gear, and art that I thought I’d present the case for Near Vertical Incident Skywave (NVIS) and share my learnings and experiences regarding this important radio art.
Let’s start with the why. I’ve played with technology and traveled enough to experience regional power outages, communication outages, and other mayhem that happens when infrastructure fails. Thus far NVIS is the one reliable communications that is low power, field portable, and zero infrastructure.
Now, let’s establish what NVIS is; Wikipedia has a nice description here – https://en.wikipedia.org/wiki/Near_vertical_incidence_skywave
If you’d like a simple demonstration, go into your yard, point a hose straight into the sky and turn it on. One quickly notices the water pattern falling back to the ground. That is what NVIS essentially seeks to accomplish; but reflecting RF off the F-layer of the ionosphere and then creating a pattern roughly a few hundred miles in diameter.
Understanding NVIS is one thing, being able to use it in a true grid-down / field-portable environment require understanding and enough practice so you can rely on your knowledge, skill, and gear if it ever needs to be put into practice. In future articles we will cover aspects of this; radios, antennas, propagation (band conditions), power, etc.
Thanks for reading and I hope you get something from my ramblings. Post a comment and let me know your questions, comments, and thoughts.