Parabolic range extenders. Do they really work?

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They help but not even close to a flat panel like a maxxuav DB2, parabolics like flat panels focus all the signal forward so you have to make sure you are pointing directly to the craft, if not it will be worse. I used a pair when I got my P4 many moons ago and it did help somewhat, then I got a flat panel and it was a game changer.
You are right, I upgraded from the parabolic to the ITELITE 14dBi flat panel. The range is crazy good. I use it on my P4P. I also have a P3s that I bought before the P4p and on the P3s I have the FPVLR. It's also great. The ITELITE flat panel may be a smidge better but that's just me. Either one of those will extend your range alot.
 
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Not trying to be rude here but flying 2 miles is asking for trouble. You guys must have very good eye sight. I get scared as soon as I lose visual sight of my drone. Guess I'm a coward lol.
no, you're sensible and you follow the rules.
 
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Don't know why they didn't work on your p4 but they work great on my p3p.... I get 2 miles easy..but you have to keep them pointed at the bird.
 
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Well, today I flew without the parabolic reflectors. Got out to nearly 1700m and then the signal went to 2 bars. I quickly slipped on the reflectors and immediately the signal went to zero and the display went to black and white. I removed the reflector and immediately, the signal went to 2 bars and around 100m later, it all cut out and the Phantom headed for home.

I honestly have no idea what’s going on. In every other aspect, the P4A Plus is an amazing machine but this crazy and unpredictable behaviour is driving me a little crazy!
 
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Well, today I flew without the parabolic reflectors. Got out to nearly 1700m and then the signal went to 2 bars. I quickly slipped on the reflectors and immediately the signal went to zero and the display went to black and white. I removed the reflector and immediately, the signal went to 2 bars and around 100m later, it all cut out and the Phantom headed for home.

I honestly have no idea what’s going on. In every other aspect, the P4A Plus is an amazing machine but this crazy and unpredictable behaviour is driving me a little crazy!
Jay, if you google parabolic antenna design you'll find these devices are not even close to what a proper design requires. From what I've seen on the web they are not even parabolic. One of the rules of thumb is that the dish should be at least 10 wavelengths wide. At 2.4GHz this would mean an antenna 49 inches wide. They are a waste of money.
 
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Jay, if you google parabolic antenna design you'll find these devices are not even close to what a proper design requires. From what I've seen on the web they are not even parabolic. One of the rules of thumb is that the dish should be at least 10 wavelengths wide. At 2.4GHz this would mean an antenna 49 inches wide. They are a waste of money.
Explain how a Pringle’s can wifi booster provides such high directivity? It looks even less like a sat TV dish. Tell the guy who had had his wifi hacked they don’t work.

They do work. Nowhere near as efficient as a larger dish but they work nonetheless. You can increase directivity at audio frequencies using a salad bowl or traffic cone. What do you think the wavelength of audio frequencies is?

Even if the reflector provided no forward gain (it does) it will be reducing signal strength of any devices/interference behind the operator. This can improve range significantly.
 
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Well, today I flew without the parabolic reflectors. Got out to nearly 1700m and then the signal went to 2 bars. I quickly slipped on the reflectors and immediately the signal went to zero and the display went to black and white. I removed the reflector and immediately, the signal went to 2 bars and around 100m later, it all cut out and the Phantom headed for home.

I honestly have no idea what’s going on. In every other aspect, the P4A Plus is an amazing machine but this crazy and unpredictable behaviour is driving me a little crazy!
I couldnt begin to explain your conundrum, but i have the Polarpro parabolic extenders that Best Buy sold for the P3P (same size antenna), and they perform famously on the P4P still. I can fly out three miles over a wifi congested area. I even made some by cutting coke cans in half just to try. They worked as well. Its simple technology, odd that its ineffective in your case.
 
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Explain how a Pringle’s can wifi booster provides such high directivity? It looks even less like a sat TV dish. Tell the guy who had had his wifi hacked they don’t work.

They do work. Nowhere near as efficient as a larger dish but they work nonetheless. You can increase directivity at audio frequencies using a salad bowl or traffic cone. What do you think the wavelength of audio frequencies is?

Even if the reflector provided no forward gain (it does) it will be reducing signal strength of any devices/interference behind the operator. This can improve range significantly.
Those Pringle can atennas work well because they follow established engineering priciples. It doesn't look like a sat dish is because it isn't. It is a Yagi type which is an entirely different animal. The reflected signal doesn't always sum with the primary wave. In fact it arrives a little late and out of phase subtracting from each other and you get even less signal. In FM radio its called "multipath". Anyway, like I said they are rubbish.
 
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Maybe you are putting them on backwards?! I absolutely rely on mine and am extremely pleased.
 
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Those Pringle can atennas work well because they follow established engineering priciples. It doesn't look like a sat dish is because it isn't. It is a Yagi type which is an entirely different animal. The reflected signal doesn't always sum with the primary wave. In fact it arrives a little late and out of phase subtracting from each other and you get even less signal. In FM radio its called "multipath". Anyway, like I said they are rubbish.
Anyway? The Pringles can isn't a yagi- the best description would be waveguide actually.

The range extender is placing the standard DJI dipole at the focal point of the reflector.

They might be rubbish but they do work.

Have you tried them?
 
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The wavelength at 2.4ghz is 12.5 cm. As far as I know (and I fully admit that my physics is old!), if the focal point, where the antenna is, is less than this or not a multiple of this number, you WILL get destructive interference of the signal because the reflected signal will be out of phase with the non reflected signal.
This is likely to result in areas where the signal is good (constructive interference) and other areas where the signal is bad (destructive interference).
Since none of these reflectors are 12.5cm away from the anntennas, how can they work?
Don’t want to get into the wave vs particle nature of radio waves here!

Ps loved the comment about the reflectors being back to front!
 
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The wavelength at 2.4ghz is 12.5 cm. As far as I know (and I fully admit that my physics is old!), if the focal point, where the antenna is, is less than this or not a multiple of this number, you WILL get destructive interference of the signal because the reflected signal will be out of phase with the non reflected signal.
This is likely to result in areas where the signal is good (constructive interference) and other areas where the signal is bad (destructive interference).
Since none of these reflectors are 12.5cm away from the anntennas, how can they work?
Don’t want to get into the wave vs particle nature of radio waves here!

Ps loved the comment about the reflectors being back to front!
Think about the reflector in a vehicle driving light or a torch (flashlight).... they vary in performance however they also vary greatly in dimensions- they all work yet the wavelengths if visible light are constant. These simple range boosters are simply placing the driven element at the focal point of the reflector. They are crude and inneficient but they do work. 1/4 wavelength of 2.4 ghz isn’t much off the antenna to reflector spacing on a lot of these units.

Arguably they are largely a waste of time given the current unaided performance of lightbridge, occusync etc.
 
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They do work and no amount of balking will prove otherwise. The increase is nominal, but they do show an increase.Take yours and throw them out. We've used them and know the truth. I personally depend on advanced methods, but already have seen the effects of the foil panels. Also... I use them on my home wifi extender and again, see them work every day. If you want to see real magic, then use actual boosters and flat panels. Then try to argue their ineffectiveness...
 
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Jay, if you google parabolic antenna design you'll find these devices are not even close to what a proper design requires. From what I've seen on the web they are not even parabolic. One of the rules of thumb is that the dish should be at least 10 wavelengths wide. At 2.4GHz this would mean an antenna 49 inches wide. They are a waste of money.
You obviously haven't used one yourself and compared. They do work, however the fixed antenna spacing on the RC doesn't allow for optimal performance, granted. But they do help and well worth the $5 to 15 they cost.
 
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Well, today I flew without the parabolic reflectors. Got out to nearly 1700m and then the signal went to 2 bars. I quickly slipped on the reflectors and immediately the signal went to zero and the display went to black and white. I removed the reflector and immediately, the signal went to 2 bars and around 100m later, it all cut out and the Phantom headed for home.

I honestly have no idea what’s going on. In every other aspect, the P4A Plus is an amazing machine but this crazy and unpredictable behaviour is driving me a little crazy!
OK, now that you have confirmed you have a P4A, this uses only 2.4Ghz, same radio as the P4. You are posting this in the P4P (these use completely different radios with 5.8Ghz) section of the forum so it's important you tell us exactly what you have. Your first post stated P4.

Sugestion:
For the P4A, go into the channel section of the app. Choose a custom channel manually that has the least traffic. You'll see the 2.4Ghz traffic for each channel, select the least busy channel. AFTER you select a channel manually, you will see an option pop up to set the "Transmission quality". This only appears AFTER you choose a custom channel. Set the Transmission quality to 4mbps. Try that and see how it works for range.

As for the GL300C that you are using with that P4A, for some reason DJI made the GL300C with a weaker radio. If you measure the signal strength from the radio with an RF meter, you can compare and see it's inherently weaker than the GL300A from the P3P. You can check out my test results on this from 2016. Since this radio is inherently weaker, I used the Inspire controller with my P4 and then got what I call "normal range" support from my P4 of 2-3mile (FCC). The windsurfer parabolic antenna helps, but not nearly as good as when using GL300A or GL658A controllers. I finally installed an Itelite antenna onto my GL300C and that seemed to work much better, helping optimize the inherently weak RF radio in the RC. But I still use the Inspire controller with my P4.
 
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Determining the focal length of a parabolic dish
Parabolic Dish Reflector
http://www.analyzemath.com/parabola/parabola_focus.html

The backing is also important. If the foil used is cheap and too thin, then it will have reduced reflecting power. Thick copper foil is the best.

The articles explain the position of the focal point. The position of the antenna in relation to the reflector is important
Actually not so much since microwaves are very much "skin effect" sort of frequencies.
That said it *does* have to be a good conducting metal - just thickness isn't too much of a concern since we're only talking a couple watts.
 
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Millimeter waves are VERY much in subjection to any variance. distances ( foremost to the reflector), power, angles and all materials. First, the material used to reflect is the thing to consider most. Gold, being the best densest metal is the most desirable to use. Now considering Amazons pricing structure and the average consumer ability, gold is out of the ballpark as far as affordability is concerned. Next is copper, the most widely used. Next is copper/aluminium. The very percentage has an effect although as you say, the wattage and typical use has little observable differences. Next, is the use of "Mylar" although this does still reflect signal and is still useable, it is not copper or aluminium or gold. I have no proof of the use of Mylar in the place of denser metals it is a suspectable direction given the tricks of the trades.... What the most important thing is, after the use of proper metal backing is the curve of the parobolic curve combined with the distance of the antenna element to the parabolic plate/dish. Considering the small energy of the millimeter signal, every dimension is paramount. As well as the material used. Combined, every aspect will contribute to the output, performance and end "Phantom magic happiness" of the consumer. As a testor, and experimentor, I have found said end result best by just blasting the microwaves out there as a "Rambo" of the millimeter plane. RX is the very thing needed to have your flights "end well". Although "RX" is not at stake in heath concerns, I always ask if nearby observers have a pacemaker and/or a substantial heath plan before the switch is flipped. Then I warm my coffee before the flat panel antennas as I take off to unparalleled saturation levels. Foil plated parabolics have their place, as do outright occiliation of the unseen high frequency of 2.4ghz. Migratory birds may have to delay their journeys, but I get the footage sought.
 
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Hint: The receive (RX) is the secret. Transmit (TX) is irrelevant mostly.... (Controller side)
 
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Hint: The receive (RX) is the secret. Transmit (TX) is irrelevant mostly.... (Controller side)
It's interesting you say that. Normally I would agree you when flying my P3P, however with my P4 I seem to lose control signal more than video. This triggers immediate RTH, which I don't like. When I lose control signal on the P4, the video feed will immediately disconnect also, even though I have a couple bars on the video feed. That's what's so wierd with the P4. Since the Tx control signal is so little data, in comparison to the video downlink data rate, I would think the control signal would be easy to maintain a good connection, like the P3P. But the P4 acts a bit weird in this regard, losing control signal first, due to the weak GL300C controller.

With my P3P I would always lose video signal first. When that happens, I ALWAYS still had control of the craft and could easily ascend to a higher altitude to regain video signal. This is how I prefer to lose signal, by losing video first instead of control first. However with P4 I would always lose control first, with immediate disconnect of video feed when that occurs. Then I started using the Inspire GL658A RC which has 50% more control transmit RF power than the GL300C. When using the Inspire RC with my P4, the craft would act more like my P3P, having a much more reliable control signal, and losing video signal first, the way I like it. I prefer losing video first, not control, so I can still ascend to regain video signal.

Although I speak of P4 here, it's relevant to the P4A issue being discussed in this thread, since it uses the same GL300C, which I deem weak.
 
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OK, now that you have confirmed you have a P4A, this uses only 2.4Ghz, same radio as the P4. You are posting this in the P4P (these use completely different radios with 5.8Ghz) section of the forum so it's important you tell us exactly what you have. Your first post stated P4.

Sugestion:
For the P4A, go into the channel section of the app. Choose a custom channel manually that has the least traffic. You'll see the 2.4Ghz traffic for each channel, select the least busy channel. AFTER you select a channel manually, you will see an option pop up to set the "Transmission quality". This only appears AFTER you choose a custom channel. Set the Transmission quality to 4mbps. Try that and see how it works for range.

As for the GL300C that you are using with that P4A, for some reason DJI made the GL300C with a weaker radio. If you measure the signal strength from the radio with an RF meter, you can compare and see it's inherently weaker than the GL300A from the P3P. You can check out my test results on this from 2016. Since this radio is inherently weaker, I used the Inspire controller with my P4 and then got what I call "normal range" support from my P4 of 2-3mile (FCC). The windsurfer parabolic antenna helps, but not nearly as good as when using GL300A or GL658A controllers. I finally installed an Itelite antenna onto my GL300C and that seemed to work much better, helping optimize the inherently weak RF radio in the RC. But I still use the Inspire controller with my P4.
Hi!
I do have the P4A Plus but since I’m talking about distance flying, I thought that the 5.8gHz part of the transmission signal was largely irrelevant. As far as I understood, the 5gHz signal was mainly for flying close by in congested WiFi areas as the 5gHz bands are usually a lot less congested!
 

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