FPV relay idea?
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Theoretically possible but not really practical. Much easier to just use a more appropriate frequency and/or antenna setup to get greater range. The more pieces in the chain the greater potential for a failure at some point causing loss of video or control, not to mention the latency of relaying a real time signal.
Ken
helloman1976
Ziptie Relocation Expert
It can be done but there's a better way. Do what the Germans did during WWII and use a blimp or hot air balloon. If you use a balloon you could use hard wire instead of beaming the signal down. The wire itself would be the tether to the balloon and this setup would give you HUGE range advantages. Let us know if you try it, I want to see a video.
DucktileMedia
Drone Enthusiast
Would it really make that big of a difference? Seems the whole sky is littered with interference. Like Ken said, just choose a better frequency.
helloman1976
Ziptie Relocation Expert
I think he's talking conceptually can it be done. The answer is yes it can be but to Iris point you can select another channel OR you can go to a setup that's free of ground floor noise. 900mhz has a lot of ground floor noise and is great outside of city limits however anywhere close to a cell phone town and you'll get a ton of interference. 1.3Ghz is fantastic and is not used nor is there much noise on that channel plus you get to keep the penetration of low frequency versus something like 5.8Ghz which is fast and clear but LOS only.
Iris, "would it really make that much difference?" Absolutely as long as there wasn't interference on that channel, if you were just looking to increase your range on an open channel then height is your very best friend and it would be a night and day difference.
RotorJockey
Member
There are a few ways to do this. You will need at least a twisted pair of insulated wires from the balloon. At the balloon you would have to have an FPV receiver (like you would have on the ground) and a line amplifier/impedance matcher like the one described by TEXAS instruments at: http://www.ti.com/lit/an/snoa422b/snoa422b.pdf
Remember also, that the true horizon (as opposed to the actual horizon to the trees etc.) is a function of:
d (Km to horizon) is approx 3.75 x sq. root of observer's height in meters. Therefor d=3miles for h=6ft, d=24mi for h=330 ft, & d=69mi for h=2717ft (at the coast).
Just some thoughts ...
Remember also, that the true horizon (as opposed to the actual horizon to the trees etc.) is a function of:
d (Km to horizon) is approx 3.75 x sq. root of observer's height in meters. Therefor d=3miles for h=6ft, d=24mi for h=330 ft, & d=69mi for h=2717ft (at the coast).
Just some thoughts ...
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helloman1976
Ziptie Relocation Expert
Yes! Now you're thinking, excellent and well put. Height of eye is always an excellent way to increase range. This is why they put antennas on the tops of towers and buildings and not flat on the ground
Another option would be to put the antenna on the balloon and receiver on the ground but the resistance of the antenna cable would probably be pretty high.helloman1976
Ziptie Relocation Expert
The higher you are, generally speaking, the longer your radio signal will be received and the lower you are the exact opposite. You have a better chance at 1 mile away and 500 feet up than you do at 1 mile away and 5 feet off the ground of receiving a signal.
tamulmol
Member
Yah but I mean whats the purpose of having high vrx antenna if you're just sitting low with your uhf radio. Youll see the video but you wont be able to control it right?
helloman1976
Ziptie Relocation Expert
The purpose would be to extend the range of your video transmitter which is the weakest link in that setup. UHF radio will go around 25Km with no issues at all where most video setups may go 10-20Km with a perfect setup but a more typical setup around 6-10Km.
Droider
Drone Enthusiast
This has all got be to flight time dependent, what quad is going to fly for miles anyway.. Oh and I thought in most countries flying beyond line of sight was a no no.
I here of people flying planes miles and miles no problem BUT one day with all this advanced technology easily available to fly further and further there is going to be a disaster. The CAA over here in the UK now have a team on the hunt for people to prosecute after a few near misses with commercial and recreational full size aircraft.
Think long and hard before flying FPV BLOS and if you are going to do it anyway at least check for NOTAMS in the area you are going to fly and just remember its not only our hobby and your freedom you are jeopardising but its also other peoples lives.
Slight rant over.
I here of people flying planes miles and miles no problem BUT one day with all this advanced technology easily available to fly further and further there is going to be a disaster. The CAA over here in the UK now have a team on the hunt for people to prosecute after a few near misses with commercial and recreational full size aircraft.
Think long and hard before flying FPV BLOS and if you are going to do it anyway at least check for NOTAMS in the area you are going to fly and just remember its not only our hobby and your freedom you are jeopardising but its also other peoples lives.
Slight rant over.
helloman1976
Ziptie Relocation Expert
This thread is more about theory and how to get the longest range. For those of us not in the UK I don't think it matters much right now especially if you are flying in remote areas where no one lives like the desert or mountains etc. The basic idea of this thread is called "height of eye". The higher the antenna, the longer the range etc....
Droider
Drone Enthusiast
@helloman, errr the tread is called 'FPV relay idea' oh and by the way no matter where you fly UK or anywhere if you cause an incident you will be held responsible. Yes we all know the technology is there to do it but its about responsibility. Desert, mountains, local parks it makes no odds, once you don your FPV goggles your peripheral vision is gone, your awareness of what is around you 500m out has gone, you do not know what is behind, below, above left or right.
Guess this is a matter of opinion but as far as I am concerned FPV should only be used with a observer ALWAYS keeping the craft in site and in contact with the pilot to make him aware of what the immersed pilot may not be aware of.
Example, only a couple of days ago I was working LOS. I had check the NOTAMS in the area I was operating and was perfectly clear to work LOS and to an altitude of 400ft. I carried out the flight and landed, as I landed I heard a plane, it was a Army C130 flying down the Loch at 200ft not 300ft from my take off position. This totally freaked me out. I rang the local ATC and was told they do that now and again! Now you are 1km out FPV and even though you think you are not going to cause any problem to anyone how do you really know. The answer is you don't, you could cause a massive problem.
Anyhow I dont agree with FPV flight BLOS of an observer...so thats me done.
Dave
Guess this is a matter of opinion but as far as I am concerned FPV should only be used with a observer ALWAYS keeping the craft in site and in contact with the pilot to make him aware of what the immersed pilot may not be aware of.
Example, only a couple of days ago I was working LOS. I had check the NOTAMS in the area I was operating and was perfectly clear to work LOS and to an altitude of 400ft. I carried out the flight and landed, as I landed I heard a plane, it was a Army C130 flying down the Loch at 200ft not 300ft from my take off position. This totally freaked me out. I rang the local ATC and was told they do that now and again! Now you are 1km out FPV and even though you think you are not going to cause any problem to anyone how do you really know. The answer is you don't, you could cause a massive problem.
Anyhow I dont agree with FPV flight BLOS of an observer...so thats me done.
Dave
helloman1976
Ziptie Relocation Expert
It is a matter of opinion however this thread is about how to increase the range of your video and will raising the height of your antenna increase your range, i.e. "height of eye". You're entitled to your opinion Dave and you're welcome to share it however as long as no laws are being broken people can and will fly however they'd like regardless of how you feel about it but thanks for sharing.