Modded the Mavic 3's Remote with Alientech's Amplified Duo Antenna, compared range with unmodded remote w/ Yagi Antennas.

[cgmaxed]

Regardless of all the negative vibes sent in this thread mate, I for one appreciate the info on the hardware mod you have done, always fascinated on pushing the limits on current hardware, not seen anyone else do it yet, so cheers.

Thanks.

I hope the hardware specifics and results can help others decide how they may wish to proceed if they need a stronger signal in VLOS or otherwise.

The R/C pro may be an alternative to getting a better signal, but it's pretty expensive compared to a hardware mod.

 

[Cobra193]

Comment unnecessary.

So is this thread. I’m frankly surprised these threads are allowed to begin with. I’m not a BVLOS purist. I believe you can momentarily lose sight, and I also believe BVLOS shouldn’t be enforceable in unpopulated areas where there is no manned air traffic. But to intentionally setup and regularly fly BVLOS is reckless and posts like this that contribute to this practice shouldn’t be allowed.

You could argue these threads should be allowed so people can fly BVLOS in remote, unpopulated areas, but then a disclaimer stating that should be included.

 

[dirkclod]

So is this thread. I’m frankly surprised these threads are allowed to begin with. I’m not a BVLOS purist. I believe you can momentarily lose sight, and I also believe BVLOS shouldn’t be enforceable in unpopulated areas where there is no manned air traffic. But to intentionally setup and regularly fly BVLOS is reckless and posts like this that contribute to this practice shouldn’t be allowed.

You could argue these threads should be allowed so people can fly BVLOS in remote, unpopulated areas, but then a disclaimer stating that should be included.

If you don’t want to read about it. Don’t .Must have missed my prior post to stay on topic. As far as disclaimers…
15. The Community Owners strongly encourage users to obey all federal and local laws and regulations when flying. It is a helpful service to the community when members guide others in understanding and following the regulations. Meanwhile, fully understanding all international rules and regulations is complex and it is not the responsibility of the community owners, moderators or community members to police and enforce these rules and regulations.
That said all that has been posted I have ether deleted or posted
on staying on the original topic.
Now from here on I will delete and warn any member that does not
heed this post.
Disagree fine contact in a message to a Admin.

 

[sax_man_al]

If you want to do this test and remain within the law, can you set up a second controller? The second pilot stays with the drone, the pilot with the modded controller can jump in a soft top and drive off, watching how the signal behaves. That way you can get further away in the same time, and, if there were any issue there's a pilot with control of the drone within VLOS. You could even not take off to save battery even more and drive away further!

 

[cgmaxed]

If you want to do this test and remain within the law, can you set up a second controller? The second pilot stays with the drone, the pilot with the modded controller can jump in a soft top and drive off, watching how the signal behaves. That way you can get further away in the same time, and, if there were any issue there's a pilot with control of the drone within VLOS. You could even not take off to save battery even more and drive away further!

DJI's consumer/ prosumer drones, I don't believe are capable of have two or more remotes assigned to them at any one time. Once one remote is linked, all other remotes are no longer able to function with that particular drone. I'/m not sure why most drone manufacturers do this, but I suspect it is a security reason, so your drone can't be hacked by another remote. I'm just guessing this. Why we can't use 2 or more remotes to control the same drone really doesn't make sense to me. Professional drones allow it, but consumer drones don't. Maybe, the law has something to do with it. One remote to one drone at a time makes it easier to prosecute the drone pilot, if he/she does something wrong. If they won't have to look for a possible second or third drone pilot., prosecution becomes easy.

Again, I'm just guessing. Who knows what the real reason is. I still don't understand why more than 2 remotes can't be assigned. One being primary and one being secondary in case the primary loses control. Maybe it's not a law thing, but a cost prohibitive setup.

 

[Ty Pilot]

DJI's consumer/ prosumer drones, I don't believe are capable of have two or more remotes assigned to them at any one time. Once one remote is linked, all other remotes are no longer able to function with that particular drone. I'/m not sure why most drone manufacturers do this, but I suspect it is a security reason, so your drone can't be hacked by another remote. I'm just guessing this. Why we can't use 2 or more remotes to control the same drone really doesn't make sense to me. Professional drones allow it, but consumer drones don't. Maybe, the law has something to do with it. One remote to one drone at a time makes it easier to prosecute the drone pilot, if he/she does something wrong. If they won't have to look for a possible second or third drone pilot., prosecution becomes easy.

Again, I'm just guessing. Who knows what the real reason is. I still don't understand why more than 2 remotes can't be assigned. One being primary and one being secondary in case the primary loses control. Maybe it's not a law thing, but a cost prohibitive setup.

I have talked to the guys that brought the first spread spectrum wifi radio to the RC market in 2004. The way it was explained is; that these radios do not operate on a single 'channel' or frequency like a typical radio or old RC remote controller.

Once these radios are connected to the controller they are designed to resist other similar frequencies, even from the exact same or duplicate controller. This is why you can put any number of similar drones with their pilots standing shoulder to shoulder with their controllers and you will get no interference. It is part of the design. I am guessing that DJi's proprietary Occusync operates very similarly.

Back in the 'old' days (here in the US) there were about 60 channels that were allotted to the RC community - when you bought an RC radio and receiver package they were each tuned to a specific frequency that correlated to a number to make it simple. In my case I always flew on channel 51. But here is the problem - there were a couple thousand or more such pilots also flying on that exact same channel channel.

As you can imagine this can and did cause problems so there had to be a protocol in place. Simply put you had to wait for the channel to become free and then you could get the 'pin' that signified the channel was in use and hope some newb didn't pull up to the pits and turn on even for a second.

When Spread Spectrum technology came out this changed everything and we can now turn on our drones just about anywhere we want and have a safe secure connection. But the flip side of that coin is that multiple controllers for a single unit using the current technology is not likely.

I'm not saying that multiple controllers for a single craft is impossible, because it is possible, but from a business standpoint, it would make no sense to put this kind of functionality in a consumer drone because the majority of consumers (recreational and commercial) would neither need, or pay for that capability in my opinion.

 

[MAvic_South_Oz]

DJI's consumer/ prosumer drones, I don't believe are capable of have two or more remotes assigned to them at any one time. Once one remote is linked, all other remotes are no longer able to function with that particular drone. I'/m not sure why most drone manufacturers do this, but I suspect it is a security reason, so your drone can't be hacked by another remote. I'm just guessing this. Why we can't use 2 or more remotes to control the same drone really doesn't make sense to me. Professional drones allow it, but consumer drones don't.

M1P / MPP can do that, not sure if M2 could, but maybe Fly app / newer controllers aren't adapted for it.

 

[AZDave]

I have talked to the guys that brought the first spread spectrum wifi radio to the RC market in 2004. The way it was explained is; that these radios do not operate on a single 'channel' or frequency like a typical radio or old RC remote controller.

Once these radios are connected to the controller they are designed to resist other similar frequencies, even from the exact same or duplicate controller. This is why you can put any number of similar drones with their pilots standing shoulder to shoulder with their controllers and you will get no interference. It is part of the design. I am guessing that DJi's proprietary Occusync operates very similarly.

Back in the 'old' days (here in the US) there were about 60 channels that were allotted to the RC community - when you bought an RC radio and receiver package they were each tuned to a specific frequency that correlated to a number to make it simple. In my case I always flew on channel 51. But here is the problem - there were a couple thousand or more such pilots also flying on that exact same channel channel.

As you can imagine this can and did cause problems so there had to be a protocol in place. Simply put you had to wait for the channel to become free and then you could get the 'pin' that signified the channel was in use and hope some newb didn't pull up to the pits and turn on even for a second.

When Spread Spectrum technology came out this changed everything and we can now turn on our drones just about anywhere we want and have a safe secure connection. But the flip side of that coin is that multiple controllers for a single unit using the current technology is not likely.

I'm not saying that multiple controllers for a single craft is impossible, because it is possible, but from a business standpoint, it would make no sense to put this kind of functionality in a consumer drone because the majority of consumers (recreational and commercial) would neither need, or pay for that capability in my opinion.

Yes, you have that correct. Spread spectrum means that the signal hops around several frequencies, and before it makes a hop it sends a code to tell the receiver where to listen next. It is a very efficient way to way to make the best use of a batch of frequencies, but as you say it makes it very difficult for a second controller to just jump in and take control.

Interestingly enough, the original patent for the basic concept of spread spectrum transmission was granted to movie star Hedy Lamarr back in 1942.

 

[stavok]

Yes, you have that correct. Spread spectrum means that the signal hops around several frequencies, and before it makes a hop it sends a code to tell the receiver where to listen next. It is a very efficient way to way to make the best use of a batch of frequencies, but as you say it makes it very difficult for a second controller to just jump in and take control.

Interestingly enough, the original patent for the basic concept of spread spectrum transmission was granted to movie star Hedy Lamarr back in 1942.

" spread spectrum transmission was granted to movie star Hedy Lamarr back in 1942."

BEST Trivia I've heard in years! AAA+++

 

[RadioFlyerMan]

Yes, you have that correct. Spread spectrum means that the signal hops around several frequencies, and before it makes a hop it sends a code to tell the receiver where to listen next. It is a very efficient way to way to make the best use of a batch of frequencies, but as you say it makes it very difficult for a second controller to just jump in and take control.

Interestingly enough, the original patent for the basic concept of spread spectrum transmission was granted to movie star Hedy Lamarr back in 1942.

I proved it for myself with my dual, co-located RC fixture. RC’s 6 inches apart have shown no interference for two Mavics at VLOS distances.

 

[Heavydpj]

... However, the people in the car can act as spotters or visual observers so I guess it'd be legal.

No. It would absolutely NOT be legal. The operator must keep the craft in sight throughout the entire flight sequence, as must the spotters.

 

[Heavydpj]

Regarding VLOS, having spotters in cars communicating with the pilot electronically isn't approved by the FAA. You have to have unaided communications. I know, it makes no sense. Ask yourself, How does a control tower communicate with an airplane pilot?. They use electronic communications. Why drone pilots and spotters aren't allowed to do the same doesn't make sense. I personally think flying drones with spotters using electronic equipment as phones or walkies would be a safer system than using spotters that need to stand close enough to the pilot to physically verbalize that they see the drone. The logic doesn't make sense.

The issue is not communications, the issue is that the PIC and VO must have the craft in sight through the entire flight operation.
§ 107.31 Visual line of sight aircraft operation.

(a) With vision that is unaided by any device other than corrective lenses, the remote pilot in command, the visual observer (if one is used), and the person manipulating the flight control of the small unmanned aircraft system must be able to see the unmanned aircraft throughout the entire flight.

and

§ 107.33 Visual observer.

If a visual observer is used during the aircraft operation, all of the following requirements must be met:

(a) The remote pilot in command, the person manipulating the flight controls of the small unmanned aircraft system, and the visual observer must maintain effective communication with each other at all times.

(b) The remote pilot in command must ensure that the visual observer is able to see the unmanned aircraft in the manner specified in § 107.31.

 

[Rockl]

Both controllers from the Mavic Air 2, Mavic Air 2S, DJI Mini 2, and the Mavic 3 Standard are exactly the same. In fact, you can fly the M3 with any of those controllers. I did the test. Every time you switch from aircraft the firmware needs to be reflashed and is done by the DJI FlyApp.

The funny fact is that they can produce OccuSync 2 and OccuSync 3. OccuSync 3 when is paired to the Air 2S but they downgrade to OccuSync 2 when is paired to the M3 in purpose to make you buy the RC Pro controller when the controller can talk OccuSync3.

The Smart Controller does not have SMA connectors from the factory. You need to open and mod and change the plate. I have pictures of mine when I moded. In the mod show, QMA is the Allientech connector. I have QMA to SMA converters when I want to use my 4hauks XR antenna.

View attachment 139879


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I like the Alientech mod kit for the original Smart Controller. That was needed due to the stock antenna design not having a suitable mounting surface for QMA connectors. Luckily, DJI moved the SD card and HDMI & USB ports to the front and used two independently mounted antennas for the new/Pro version of the Smart Controller. So while it wasn't easy disassembling the Smart Controller Pro, the standard Alien Tech IPX to QMA connectors work great on the Pro version with no housing modifications required.

 

[zeusfl]

That was very good to know. Thanks for the tip.

 

[zeusfl]

By the way. I have my smart controller with the Allientech Duo II for sale if someone is interested.

 

[Lasidora]

I

I like the Alientech mod kit for the original Smart Controller. That was needed due to the stock antenna design not having a suitable mounting surface for QMA connectors. Luckily, DJI moved the SD card and HDMI & USB ports to the front and used two independently mounted antennas for the new/Pro version of the Smart Controller. So while it wasn't easy disassembling the Smart Controller Pro, the standard Alien Tech IPX to QMA connectors work great on the Pro version with no housing modifications required.

Are you seeing much difference in range/ penetration, as I see you are located in FCC location, the RC-Pro is rated at nearly 1995mw output there, so nearly 2w the Alientech Duo II at most is 3db power increase, maybe with added direction improvement in the antenna compared to stock.

 

[Rockl]

I

Are you seeing much difference in range/ penetration, as I see you are located in FCC location, the RC-Pro is rated at nearly 1995mw output there, so nearly 2w the Alientech Duo II at most is 3db power increase, maybe with added direction improvement in the antenna compared to stock.

I've only used it a couple of times since making the mod. I plan to do a comparison of the amplified Alientech Duo vs. a passive directional antenna to evaluate the differences. To your point, if the base power is already 2w, the additional amplification may not produce measurable improvement above a high-gain directional antenna.

 

[AZDave]

I

Are you seeing much difference in range/ penetration, as I see you are located in FCC location, the RC-Pro is rated at nearly 1995mw output there, so nearly 2w the Alientech Duo II at most is 3db power increase, maybe with added direction improvement in the antenna compared to stock.

Feeding 2 watts into an amplifier that can only put out 2 watts is zero dB gain. But as you say, directional antennas could add considerable to that ... although not more so than directional antennas would for the stock 2 watts.

 

[Phantomrain.org]

This may have been a BVLOS range test, but "Range Test" can also be referred to as a "Signal Strength Test". These range tests can help those who have problems with signal strength at VLOS, or in areas where they are in VLOS, but with lots of obstructions and signal interference. BVLOS range tests can provide info on hardware mods that may be usable in such conditions.

For those of us that really enjoy flying from inside the car these mods mean a great deal. What is most important is Signal Strength because that goes hand in hand with Safety of flying your drone , so I am a fan.

With Range test coming to the end of an Era. We need to focus on other ways to test the Drones signal strength so I can fly with confidence , which is really what a range test is for . A one time charlie test to gain confidence in the drone.

My favorite was flying the smart controller with no antennas out 2500 ft and getting disconnected , than turning on the SC Alien Dual to see if it was really working and gaining back signal.

I also would point the SC in the Opposite direction to see if I could maintain a signal. and the Ailen Tech Dual did well.

I am tempted to use My Alien Tech with the Mavic 3 but have yet to test the Occu 3 to it limits do to VLOS rules.

What are some new ways we can test the Signal Strength without breaking the rules of VLOS. ?
I want to be able to fly behind rocks , go into gulley's , and caves and under tunnels and fly under the wave curls over the lake.


Phantomrain.org
Gear to fly in the Rain. Land on the Water.

 

[AZDave]

For those of us that really enjoy flying from inside the car these mods mean a great deal. What is most important is Signal Strength because that goes hand in hand with Safety of flying your drone , so I am a fan.

With Range test coming to the end of an Era. We need to focus on other ways to test the Drones signal strength so I can fly with confidence , which is really what a range test is for . A one time charlie test to gain confidence in the drone.

My favorite was flying the smart controller with no antennas out 2500 ft and getting disconnected , than turning on the SC Alien Dual to see if it was really working and gaining back signal.

I also would point the SC in the Opposite direction to see if I could maintain a signal. and the Ailen Tech Dual did well.

I am tempted to use My Alien Tech with the Mavic 3 but have yet to test the Occu 3 to it limits do to VLOS rules.

What are some new ways we can test the Signal Strength without breaking the rules of VLOS. ?
I want to be able to fly behind rocks , go into gulley's , and caves and under tunnels and fly under the wave curls over the lake.


Phantomrain.org
Gear to fly in the Rain. Land on the Water.

Look for an RF spectrum analyzer (but not a wireless network analyzer) and put a stubby antenna on it. Finding one that covers 2.4 GHz isn't too hard ($200+ on Amazon), but finding one that covers 5 GHz is tougher. If you're out in the open on flat ground and away from obstructions, you should be able to get good relative readings a short distance from the RC. "Relative readings" means the ability to compare various options.

Absolute readings (the kind you could use to calculate usable distance if you knew the drone receiver's sensitivity and noise figure, which you don't) are going to be almost impossible ... well, actually completely impossible ... without expensive calibrated lab gear operated by somebody who knows what they are doing.

And as far as flying behind rocks, into gullies, into caves, and under tunnels, you would also need to be able to model all those reflections and know what the conductivity of every surface is.

Have I properly painted the picture? Imagine trying to predict how sound waves would behave ... then multiply the difficulty by lots of digits because of the difference in the difficulty of making the measurements for microwave RF. I'm an electrical engineer with an RF background and in my opinion the only way to fly a drone safely is to do so with a lot of margin. Trying to min/max the situation with any degree of precision is a lost cause in the real world.