There is plenty of documented footage from balloons/blimps demonstrating they can be very stable transmission platforms.
Is there evidence they are used in this capacity instead of the satellites? How many are there, and where are they? How can I spot or track them?
The issue is possible alternatives to satellite transmission.
Possible alternatives were put forth.
Transmission of signals via troposcatter and balloons is axiomatic.
Specific frequency has not been debated and as I have stated before, I have not claimed they have been used for this.
Balloons are all over the place. I am sure troposcatter is used all over the globe, especially in difficult to access.
Any possible alternative source designed to mimic geostationary satellites has to be "geostationary" for years.
Not to move in relation to the grond for more than half of a degree.
This eliminates any kind of objects flying in the air.
The only two ways to achieve this are fixed
towers or very
well anchored balloons.
The alternative also has to be high enough to appear at the same elevation and azimuth for large areas on the ground.
You can calculate height yourself from data published on several web sites, and used from there for orienting dishes all over the world.
Knowing that the highest high altitude balloon flight in history was 32.9 miles high, and it was not anchored (fixed in the sky),
this eliminates ballons, because the alternative source has to be many times higher.
Additionally, we don't see anchors every couple of miles required to keep in place that many balloons.
Towers are already eliminated, as the tallest man made structure is Burj Khalifa, 828 meters. 830 with antenna on top of it.
Every structure like that can be seen from 64 miles away, and in real life we don't see such towers every mile or two all around.
EDIT: By using alternative source you can fool small number of people concentrated in small area, like same household or very small village.
But in attempt to scale up the same thing to vast population the system quickly grows beyond concealability.