Near Vertical Incidence Skywave (NVIS) Simplified

NC Scout has a new article up at American Partisan about NVIS radio communications. If you were confused by some of the terms used in our Suggested Radio Equipment for Community Security article, this has some additional explanation of line of sight and beyond line of sight communication as well as, of course, NVIS which was briefly mentioned in that article.

HF radio wave propagation can be shot nearly straight into the Ionosphere, hence the name Near Vertical Incidence. What goes up, must come down. Knowing that all things have equal and opposite reactions, the angle coming down is also nearly vertical. Then it goes back up, and down again, and over and over. Like this:

near
Near Vertical Propagation

And it gives you a range Beyond Line of Sight, at the tactical level, like this (minus the TACSAT in the photo):

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Tactical Coverage of NVIS Comms

With a regional picture looking something like this (which goes along with Planning your Footprint) pictured below.

Washington DC
Regional Coverage Using NVIS

So what does this give us? We now have Beyond Line of Sight Communications that do not rely upon repeaters. Once operators are decently trained and have a good amount of time working in this method under their belt, it can be very reliable.

Important to note is that not all HF bands work well for this. Generally speaking, 160-40M work best due to the way the frequencies themselves refract off the ionosphere. Experience as a Radio Operator should tell you when to use which band based on noise level, the amount of heard traffic, and beacon propagation near your operating frequency will give you a good idea if your traffic will be successfully transmitted or not.

Click here to read the article in its entirety at American Partisan.

American Partisan: Realistic Redundancy

JC Dodge of Mason Dixon Tactical has a brief article up at American Partisan entitled Realistic Redundancy: Prioritization and Selection about the gear for which you should have a spare.

It was a dark and stormy winter night in Northern Iraq. My patrol had just been ambushed by bad guys, and we had casualties. Guess what “Patrol Leader”, you’ve got to call in the 9-line, ASAP! I hurry up and fill it out with a grease pencil, and start to relay the info to higher via radio. Guess what? While reading off line three, my headlamp died. “WHAT THE HELL DO I DO NOW!” is the first thought, which is immediately replaced with “Wait, I have a clip light in my front gear pocket.” I get it out, clip it to my helmet band, and am able to continue transmitting. Why am I telling you this? I bring up this example to point out why redundancy in certain areas of your gear is CRITICAL, and how you might want to prioritize what should have redundancy.

Nine line

When people in the Civilian Survivalist/LEO/Mil arena think about redundancy, it’s usually tied to the phrase “Two is one, one is none.” There’s a lot to be said for that mindset, but taken to the extreme, it will do nothing but add extra crap (that you don’t need readily available), and probably slow you down in the process, due to the extra weight it adds to your gear. Whether you are a Civilian, LEO, NPT (Neighborhood Protection Team) member, or member of the Military, understanding the need for redundancy in you essential gear, and how to prioritize it is essential to giving yourself the best chance at survival in a non-permissive environment. First we will talk about prioritization of gear that needs redundancy, then we will talk about a method to use when looking for redundant gear options.

How do you prioritize what needs redundancy? Here’s the questions I ask myself to make my decisions. 1) If I lose use of the item while in the middle of using it, could it drastically alter my chances of surviving? 2) Is the item of such importance in my line gear (1st on person, 2nd is load bearing gear, 3rd is your ruck), that not having it alters my chances of success and/or mission accomplishment? “Mission accomplishment” being different things to different people. An example of this for Survivalists would be surviving a life and death situation, whether it is natural or man made. For the LEO or legally armed civilian, it could be an “Active shooter” situation. For an NPT (Neighborhood Protection Team) member, it might be conducting operations in your AO after your area has devolved into TEOTWAWKISTAN, whether those operations are purely defensive, or what I call “Aggressive Defense”. 3) Is the weight of the redundant item that is added to my gear offset (less important than) by the importance of that item?

Let’s discuss them in order,

1) If I lose use of the item while in the middle of using it, could it drastically alter my chances of surviving? As I illustrated in the first paragraph, having that extra light (same type, a hands free design) was critical to mission success, which at that time was callin’ in the status of some of my patrol’s wounded soldiers.

2) Is the item of such importance in my line gear, that not having it alter my chances of success in mission accomplishment? Due to the “priorities of work” being done at the time, It would have been “less than optimal” to pull one of my other soldiers off of their assigned task, just to hold a light for me.

3) Is the weight of the redundant item that is added to my gear offset (less important than) by the importance of that item? In the case of the hands free light HELL YEAH! Those clip lights from a number of vendors are very small, lightweight, and can be tucked almost anywhere for a future need. The only downside is their proprietary type of small watch battery (my normal headlamp uses AA, along with almost all my electronic gear, except for a few 123’s).

Things that I think are good candidates for redundancy…

Read the entire article by clicking here.