People use 5.8ghz patch antennas for long range video link, so I was thinking of trying one on the radio. Not a tech guy, so might be a stupid idea.

Like this one:
https://hobbyking.com/en_us/immersionrc-...s_products

You generally don't want your transmitter to be using a directional antenna. Unless you plan to fly with the patch facing you the whole time (including the return trip), you will experience significant db loss. This is why even on the receiving side, we pair a patch with an omni or another patch covering an opposing line of sight.

(21-Sep-2020, 09:05 PM)the.ronin Wrote: You generally don't want your transmitter to be using a directional antenna. Unless you plan to fly with the patch facing you the whole time (including the return trip), you will experience significant db loss. This is why even on the receiving side, we pair a patch with an omni or another patch covering an opposing line of sight.

Sorry, I meant a patch antenna on the radio/controller. Especially if your radio has two antennas like my Flysky i6x.

Video signal degradation or complete loss can be overcome if it's short lived, it's still flying you might recover it. But the control side I'd be careful. Signal loss from turning your body if your out too far could be a failsafe and you plummet from the sky before you get the chance to recover.
So yes you can but you'd need to keep the quad within the directional range of the antenna. The further out you go the easier this is but the more important it is as well.

2.4 Ghz on TX control is a loser as there isn't the power to go along with the 2.4ghz signal.  Most 2.4ghz TX put out around 25mw to 50mw.  So if you want long range, go with a 900mhz system.

But yes, you could do what you want to do.  Will it be awesome, no.  Will it be better than a standard antenna on a 2.4ghz in a longer range format, yes.  Is it worth it, well that is up to  you.

It won't have any worse characteristics than a 900mhz system though due to beam width.  Even with Crosssfire, a 900Mhz system, you have to deal with the narrowness of the signal close because of how a beam antenna works.  Also, you have to know how the RF beam comes out of the patch antenna, so you have the signal facing forward.

There are lots of considerations, and really for very little gain.  

In the end, buy Crossfire.

So technically it would work but problems are:
1. low power and
2. keeping the quad inside the signal beem?

1. What if I have a 2W signal booster on the radio?

2. I can use video quality as sort of an antenna tracker, which I'm sure everyone does anyway, so as long as I don't lose video, the control link should also be good? And GPS/RTH will save it incase links do go down.

I started wondering about how to improve the control link because yesterday I read on here that my video link equipment is good for 8 miles and I think I'd be happy/battery limited already at 4 miles. I've flown a bit over 2 miles/3.56km as it is without failsafes, so who knows, I might already be 4 miles capable.

I would of course prefer to buy crossfire or other long range control link equipment but I dread the learning curve to install/use them and then there's the price.

(22-Sep-2020, 08:17 AM)Pekka Wrote: So technically it would work but problems are:
1. low power and
2. keeping the quad inside the signal beem?

1. What if I have a 2W signal booster on the radio?

2. I can use video quality as sort of an antenna tracker, which I'm sure everyone does anyway, so as long as I don't lose video, the control link should also be good? And GPS/RTH will save it incase links do go down.

I started wondering about how to improve the control link because yesterday I read on here that my video link equipment is good for 8 miles and I think I'd be happy/battery limited already at 4 miles. I've flown a bit over 2 miles/3.56km as it is without failsafes, so who knows, I might already be 4 miles capable.

I would of course prefer to buy crossfire or other long range control link equipment but I dread the learning curve to install/use them and then there's the price.

Yeah, it is all possible.  RF is RF and all you want to do is possible.  But I'm sure there will be unforeseen challenges that crop up.

I understand your concern about the learning curve to install the Crossfire system, but hey, that's why you are part of this forum.  You will get all the help you need.

Yes, switching to Crossfire comes with a price.  But it is a good and reliable system, and once you have it, you are set.  

My recommendation is to save up and buy Crossfire.....

But, part of me wants to see your home brew system come together.... If you decide to go forward with your idea, post up pics and results for us.  

I would recommend you run you idea by someone like JB, Pavel, Drone Mesh, they all will answer in a timely manner, JB and Drone Mesh have for me.  They may see hiccups you or others haven't seen on the horizon.

Good luck

You can't go by distance ratings or what you heard other people have achieved especially in a quadcopter with a carbon frame. Foam airplanes do not block the signal like a carbon frame they will almost always get more out of any system. From the airplane side antenna separation is the one of the most important consideration's when planning a build. We don't talk about this with multirotors because there really isn't any way to do this anyway.

Things like humidity, altitude, temperature start to come into play the further you go. I do my best in the winter when humidity is almost non existent where I am.

It's kinda fun to push what you have to the extreme, I'm surprised you got as far as you have. But do it safely if yout going to, where you won't drop out of the sky and hurt someone. Last thing any of us need is another drone making the news.

Well, if it's possible then I have to try it! Even though I know I will eventually get crossfire. If I know there's something out there that will improve some feature of the quad/radio/goggles, I have to have it. It's become an addiction.

I will update this thread with the results.

I do long range flights as much "in the middle of nowhere" I can. Yes, winters are good with low humidity and when you can fly out to sea after it freezes over.

This forum has already been a huge help! Wouldn't have gotten anywhere with my quad without it and I'm sure that's how it'll be with setting up crossfire.

Here's the return flight sped up/reversed after turning around at 3.56km with my current setup:

1st update. I've ordered what I think/hope is everything I need to hook up this huge 2.4ghz patch antenna to my radio.

https://ibb.co/v3fhxLz

Update 2: Got everything for the control link. Now just waiting for this huge nearby lake to freeze over to test this in practice.

Also, definitely not battery limited anymore.
6s 3300mah 30-40C lipos bumbed up the flight time from 12min on 4s 3300mah to 25min. Landed at 3.6V.

Update 3:

Did first flight with everything hooked up and pushed it straight away to that 5k mark.

Everything was just perfect flying out but connections started breaking up after turning around. GPS rescue worked so got it back but not before almost dropping it on the ice.

Don't think I'll do this ever again!

Just my 2cents

Directional Patch on radio works great. (Radio always has 2 antenna)
Ofcourse test/setup approptiate failsafe.
either long hold time for you to reposition, or GPS RTH.

Pekka
Your video is beautiful!

You fle 3.5km one way with X6B? Wow
Can you please share details of your setup.

(08-Feb-2021, 04:54 PM)romangpro Wrote: Pekka
Your video is beautiful!

You fle 3.5km one way with X6B? Wow
Can you please share details of your setup.

Thanks! Yes, 3.5km without any issues and now 5.1km with the patch antenna on radio but went into failsafe after turning around.

Control link:
Flysky fs-i6x with 2W signal booster.
X6B receiver.

Video link:
Eachine tx805s at 1.6W + VAS Ion V2 antenna
Eachine ev800d with Menace pico patch + VAS Ion V2