Areas of radio silence are odd and sometimes unexplained. There is an area of the Chihuahuan Desert in Mexico referred to as the Zone of Silence. What is going on there?
Located about 400 miles south of El Paso, this barren desert area has a reputation. Here, radio and television signals to not travel.
In the 1800s, local farmers reported hot rocks falling down from the sky, on clear days!
Visual and auditory hallucinations have been known to occur to people passing through there.
It is coincidentally, an active UFO hotspot with local stories of "alien" people wandering the desert. There are also reports of mysterious people showing up and disappearing into thin air, meteorites crashing down, unexplained ancient ruins not built by locals, and that it aligns with other strange sites, such as the pyramids in Egypt.
Balls of fiery light are said to dance around the area, sometimes even lighting scrub brush on fire.
In the 1930s, a pilot flying over the area reported that his radio and his instruments went haywire while flying over. In the 1970s, a missile flying over the area lost its bearings and crashed.
It would seem that overall, any device of communications ceases to work there. These signals include television, radio, microwave, short wave, or satellite.
Some scientists have postulated it might be the ground's magnetite content. I would guess that this would affect the ability of birds to migrate without getting lost. We humans have a bit of magnetite in our pineal gland which aids in our ability to get a sense of direction, like an internal compass.
The parameters of this zone of silence shift around, as well, which is a very distinctively odd trait, somewhat like how magnetic north and south shift. It would be interesting to see if it shifts in the same direction or same time.
One other thing to keep in mind is that "authorities" report this area is an urban legend, that there are no such anomalies there (LINK).
As the area is remote and left as a preserve, it can be difficult to get any real information about the validity of any of these claims, even the claims of zone of silence existing. For now, it remains in the files of "unsolved legends."
Great article on the area (LINK)