Had a friend over and we were talking about terrain obstruction and he just laughed and asked if I had hooked the antenna to a drone and flown it up to see how high I need to go to get max range.
We laughed and he went home. Then my gears started turning. Why not try it for 10 minutes or so. I’ve got a mavic!!
Russians did it, but they did not use a drone, they used a balloon
https://russianpatents.com/patent/232/2320058.html
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I fly with essentially the same hardware but with different software called Stratux.
Getting a few thousand feet up drastically increases the detection range exactly as you would expect.
I did consider it for a short time last year. Tethered drone, no battery, powered via speaker cable, connected via WiFi to the ground.
In my estimation, in order to have motors capable or working at 100% duty cycle, and with the weight of the system plus cable, the drone would VERY expensive. Like $2000.
Not in my “hobby” allotment.
A private drone is limited to the 400 ft height in US uncontrolled airspace. Flights in controlled airspace require a permit.
But, even at that height, the power cable weight becomes excessive.
Baloon is the solution
That’s correct, but limitations are the same. And you would need to refill it time to time.
In my neighborhood, because of proximity to the airport, limit is 300 ft. Closer areas have 100, 50 or even 0 ft.
Yeah, I’d never consider breaking the 400’ limit. I figure a PI, an external battery and length of weighted wire for an antenna would serve the purpose. I know the mavic can handle the weight for sure.
See this external battery mod for weight comparison.
Not that I would use more batteries for drone. Just an idea of putting the PI on one side and a battery to power the PI on the other.
Just something entertaining to do.
Anyway, once you clear the trees around you with a few feet, there is very little to gain by going higher.
You are virtually just adding your height to the 30,000-40,000 feet height of the plane…
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Line of sight = 288 miles, with antenna height 15 feet, plane at 40, 000 feet
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Line of sight = 311 miles, with antenna height 390 feet, plane at 40, 000 feet
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Interesting exercise using HeyWhatsThat.com.
As the old adage goes, height costs money. How high do you want to go?
Upper left – Ground level - 1266 ft above sea level (0 ft above ground)
Upper right – 25 ft. mast – current height
Center left – 35 ft. mast
Center right – 50 ft. mast
Lower left – 100 ft. mast
Lower right – 75 ft. up the tower on the hill across the street - 1404 ft above sea level (75 ft above ground)
These are good… and economical
IRIS + quadrocopter, Orange Pi board, blue dongle on an 820T2 chip, a whip antenna.
Lifting height - 75 meters. The farthest aircraft was approximately 380 km away
http://forum.adsbradar.ru/f19/eksperiment-s-letaushim-setapom-orange-pi-dongl-kvadrokopter-2135/
Balloons are used to lift long-wave antennas of naval communications equipment and for electronic warfare equipment in other troops
380km is 236 miles. I am getting that now (240 miles).
Like I said, once you clear the surrounding obstacles and you have clear view of horizon… there is little improvement you can do, mainly because the target planes are already so much higher.
In the communications they need to raise antennas because none of those are at 40000 ft (12 km) high like the planes are.
I put a PI with a blue stick, filter, and cheapo antenna in a mess sack with a Verizon jetpack wifi hot spot and flew it up to 200 feet.
Results were not very surprising. The range stayed about the same but with the terrain obstructions gone the flights in all directions increase. As expected, mostly in areas that I was not getting any coverage in. Fun little experiment.
I did get some overheating warnings from the battery and motor speed warnings too. Flight time was less then ten minutes as it ate up the battery. 
Yeah, it was pretty fun doing it. I think I’m going to get a smaller battery and then put the wifi hotspot in a second bag so I can have it hanging 100 feet below the PI. Then take the PI upto 300 feet just for fun.
