I've been enjoying flying the Spark over the last 2-3 months and have not had any major issues (apart from one time where it fell from about 1m ... probably due to compass error).

Recently I was flying the Spark in a large open area (UK NE of Heathrow's Zone and clear of controlled airspace). The RC was connected at 5.8GHz chanel 149. At about 300m distance (not height) there was an intermittent loss of connection between the RC and the drone.

I brought the drone back and changed the frequency to 2.4GHz and chose an appropriate chanel. Didn't have any loss of connection after that.

Can anyone shed some light on the subject matter of Wi-Fi frequencies, which one to use and when?

Good question and I don't know the answer, waiting for it too.

I don't have any scientific knowledge on the subject (though I think I've read that 2.4Ghz is better for long range).  I do have practical experience though, and in my tests my flights at 5.8Ghz have been terrible for connection interruptions.  My flights at 2.4Ghz have been far superior, but I've not had recent opportunity to perform the next test, which is to observe video latency.  My OTG flights have been the best so far, but if I can convince myself that a 2.4Ghz flight is satisfactory, I'd be willing to ditch the cables.

Good question and I don't know the answer, looking for someone to shed light on the subject.

Sounds about spot on for the stated Specs..  CE Regs - 5.8GHz (300m) / 2.4GHz (500m)..

Based on my experience as an Amateur Radio Operator for many years:  2.4 Ghz will transmit data farther than 5.8 Ghz due to the lower frequency and longer wavelength.  5.8 Ghz will however transmit data at faster speeds, possibly reducing latency.  5.8 Ghz though, due to shorter wavelength will be more prone to interference from solid objects such as trees, tree leaves, and even raindrops.  One of the issues with 2.4 Ghz is that so many devices use this frequency creating increased possibility of interference.  (I.E. garage door openers, microwave ovens, etc.)  Also factoring into the equation is the differences in the government maximum transmission power regulations for each band as Galchanto shows in the Spark Secs chart above.  (FCC vs. CE, etc.)  

That's my 2 cents worth.

5.8Ghz - indoors and in confined environments within a 200m range
2.4Ghz - everywhere else
To make it really straightforward - I only use 5.8 when I use the prop guards...

Is there anyway to change the default to 2.4Ghz? It's pretty annoying to do this everytime.

I'm sorry if this has been asked before (I tried to search but perhaps I'm not using the right keywords)

Thanks in advance!

El Diablo Posted at 2017-10-4 05:58
The 5.8ghz bands the Spark uses are not widely supported in EU (big mistake from their part, someone didn't do his homework). They obviously chose those because they are less 'busy'. 2.4ghz has more traffic but in EU it is the only option... The Spark is programmed to switch frecuences automatically in order to keep the best possible signal, unfortunately Dji got the exact opposite effect. if you live in heavily populated areas be prepared to loose your drone if not on the 2.4ghz channels and even so, i would rather use an OTG cable that stabilizes the connection although it is not officialy supported by Dji and voids the warranty.

ps. the Spark doesn't use the more expensive occusync system of the Mavic, instead they opted for this wifi connection. In countries outside EU the stability is widely increased.

El Diablo - What effect does OTG have on the connection between the RC and drone?

I would imagine that the direct cable connection between the phone and RC is just that. My understanding would be that whatever data that the RC is receiving from the drone is being transferred to the DJI Go app on the phone. How much does the app itself control the drone via the RC? Doesn't make sense to me to use OTG if the phone is sitting right next to the RC and connected via Wi-Fi.

I think that the 2.4 GHz / 5.8 GHz are Wi-Fi frequency bands between the RC and the drone. Is it not so?

Charles Adams Posted at 2017-10-4 05:41
I don't have any scientific knowledge on the subject (though I think I've read that 2.4Ghz is better for long range).  I do have practical experience though, and in my tests my flights at 5.8Ghz have been terrible for connection interruptions.  My flights at 2.4Ghz have been far superior, but I've not had recent opportunity to perform the next test, which is to observe video latency.  My OTG flights have been the best so far, but if I can convince myself that a 2.4Ghz flight is satisfactory, I'd be willing to ditch the cables.

Video latency is not an issue for me. If the image is delayed by less than a second, it doesn't really affect either the flight or filming.

If you're flying in sport mode with goggles through trees and objects then perhaps it would be more relevant.

All I need is reassurance that whichever Wi-Fi frequency is being used to conduct the flight does not break the connection between the RC and the drone.

mtnlandpix Posted at 2017-10-4 10:46
Based on my experience as an Amateur Radio Operator for many years:  2.4 Ghz will transmit data farther than 5.8 Ghz due to the lower frequency and longer wavelength.  5.8 Ghz will however transmit data at faster speeds, possibly reducing latency.  5.8 Ghz though, due to shorter wavelength will be more prone to interference from solid objects such as trees, tree leaves, and even raindrops.  One of the issues with 2.4 Ghz is that so many devices use this frequency creating increased possibility of interference.  (I.E. garage door openers, microwave ovens, etc.)  Also factoring into the equation is the differences in the government maximum transmission power regulations for each band as Galchanto shows in the Spark Secs chart above.  (FCC vs. CE, etc.)  

That's my 2 cents worth.

mtnlandpix - Thank you for that comprehensive reply. Makes sense.

Hi El Diablo, I think you're confusing a couple things here...

1st of all, do you use iOS or Android? I'm guessing Android hence your trouble with the 2.4 & 5.8GHz bands.

2nd the problem Android users encounter when trying to use the 2.4 GHz band (RC -> Spark) is such: in order to use the 2.4GHz band without an OTG-cable, the RC -> phone connection has to switch to 5.8 GHz. However, a lot of android devices can't connect to this band (for whatever reasons). Using a device which is running iOS solves this, as they have no trouble using this band.

In order to use the 2.4GHz band, which in Europe drastically increases range and image transmission sability, your mobile device has to connect to the RC via 5.8GHz and the RC -> Spark connection switches to 2.4GHz.
Using a OTG-cable is the only way for some android users to change the RC -> Spark connection to 2.4GHz, as the RC -> mobile device connection is no loger using WiFi and thus the 2.4GHz band becomes available.

Hope that helps.

flyingnewbie Posted at 2017-10-4 21:17
Is there anyway to change the default to 2.4Ghz? It's pretty annoying to do this everytime.

I'm sorry if this has been asked before (I tried to search but perhaps I'm not using the right keywords)

I would like to know this as well. Based on what I am reading it is recommended to fly in 2.4 however my connection seems to default to 5.8. Thanks

I ended up in this Thread because I was having the same question about 2.4GHz or 5.8GHz.
So far I have been using the default channel 149 at 5.8GHz, with signal loss at 300m even in open spaces.
Today I kept my Spark in a fixed position and walked around at far distance, with and without obstacles, and definitely noticed an improvement and increase in distance capabilities if switching to 2.4GHz.
However here 2 questions:
1) what is the best way to select the best channel in 2.4GHz? I see that while 5.8GHz menu doesn't show any stable-unstable bar, it definitely shows in the 2.4GHz menu. I guess we have to select one of the channel with the best green stable bar... is it correct?
2) Why do the specifications show a 2Km range if it looks like the distances we manage to cover are much less?
Tnxs.

Flip_L Posted at 2017-10-5 04:01
Hi El Diablo, I think you're confusing a couple things here...

1st of all, do you use iOS or Android? I'm guessing Android hence your trouble with the 2.4 & 5.8GHz bands.

Can you please tell me how can I connect my iphone to the RC via 5.8 Ghz and RC to Spark in 2.4 Ghz? (at the same time)

Within the iOs Go4 App we only (me, at least) have 2 options: We can take 2.4 or 5.8 Ghz band, which I assume is the band where the RC talks to the AC, right?

If so, as Diablo said, when you use OTG you are forcing the RC to talk to the AC in 2.4 Ghz. Right?

Nemroig Posted at 2017-10-5 08:35
Can you please tell me how can I connect my iphone to the RC via 5.8 Ghz and RC to Spark in 2.4 Ghz? (at the same time)

Within the iOs Go4 App we only (me, at least) have 2 options: We can take 2.4 or 5.8 Ghz band, which I assume is the band where the RC talks to the AC, right?

your iPhone does that automatically when you switch to 2.4GHz via the DJI GO App.

Flip_L Posted at 2017-10-5 10:26
your iPhone does that automatically when you switch to 2.4GHz via the DJI GO App.

Excuse me, I don’t get it. My iphone does what, when I switch to 2.4 ghz?

FIrst of all I had this problem, iphone and android have the same problem. As changing freq. is controlled from SPARK to CONTROLLER... Not from controller to your smart phone. This is a software issue and I fear it will never be resolved as regulation make it difficult for DJI.

I'm currently using a modded version of the DJI app. And I've not had a problem changing freq never lost connection but I use an otg connection. I don't a fear of it flying away... because I set RTH at 10% so if it ever gets that low it won't get far

My understanding of how to select 2.4GHz is to choose a channel with no bar, which means it is vacant.
Until now, I have used channel 3 and have reached more than 1000 meters (CE mode, iphone) without a single
transmission fault. Height was 60-100 meters over an open field.

I fly OTG with my Samsung tablet.  When I am connected to spark and look at the menus I see a place to select Wi-Fi  either auto or manual when I select manual I don't see an option to pick either frequency band, just select a channel.  It always reverts to auto when I leave the page.  When flying I can see that sometimes I start at the 2.4 but it almost always jumps to 5.8...Like I have no say in the issue.   

Not sure if this is the OCT cable but flying without it is horrible.   

mtnlandpix Posted at 2017-10-4 10:46
Based on my experience as an Amateur Radio Operator for many years:  2.4 Ghz will transmit data farther than 5.8 Ghz due to the lower frequency and longer wavelength.  5.8 Ghz will however transmit data at faster speeds, possibly reducing latency.  5.8 Ghz though, due to shorter wavelength will be more prone to interference from solid objects such as trees, tree leaves, and even raindrops.  One of the issues with 2.4 Ghz is that so many devices use this frequency creating increased possibility of interference.  (I.E. garage door openers, microwave ovens, etc.)  Also factoring into the equation is the differences in the government maximum transmission power regulations for each band as Galchanto shows in the Spark Secs chart above.  (FCC vs. CE, etc.)  

That's my 2 cents worth.

Nice summary.
Just a few additions:
1. the effect of trees and tree leaves is not necessarily bigger when wavelength gets shorter. when it comes to tree leaves in particular, it depends a lot on the ratio between the length of the leaves and the wavelength. That is even more true with conifer trees, such as pines - those needles act like little antennas absorbing signals at certain frequencies, depending on their lengths.
2. Keep in mind that the offered bandwidth in 5.8 is bigger. The spectrum DJI supports in 5.8 is 80MHz wide, as opposed to 50MHz in 2.4 .

Still, I agree that statistically speaking in an open environment with few other sources of RF interference - 2.4 should perform better in most places. In en environment more dense with other RF users - it's not so clear.

Jetline737 Posted at 2017-10-5 06:17
I ended up in this Thread because I was having the same question about 2.4GHz or 5.8GHz.
So far I have been using the default channel 149 at 5.8GHz, with signal loss at 300m even in open spaces.
Today I kept my Spark in a fixed position and walked around at far distance, with and without obstacles, and definitely noticed an improvement and increase in distance capabilities if switching to 2.4GHz.

The reason for the limited range you experience is that you live in Europe.
Europe acts according to the CE regulation, which limits your allowed transmission power much more than FCC does (FCC is the Federal Communication Commission of the US), FCC rules apply in the US and some other countries, their transmission power limits are more liberal allowing you bigger range.
DJI enforces the power limitations according to the area you're in. If you take your drone to the US, you should feel the difference.
See the specs of Spark (last pages of the user's manual) for theoretical ranges in each regulation.

I am in Australia and 5.8 seems to work fine. I use OTG cable on my spark  I just got an amazing 4633 metres in distance (8664 RETURN)  yes thats right. I also have phantom4 std , which only gets 6644 metres in same flight path. Both of these I use a $10- range extender purchased on Ebay. I saw on you tube someone claiming 4200 metres as world record distance for Spark so I was hell bent on breaking it and did so on Easter Sunday last weekend.

dw goldengrove Posted at 2018-4-4 01:37
I am in Australia and 5.8 seems to work fine. I use OTG cable on my spark  I just got an amazing 4633 metres in distance (8664 RETURN)  yes thats right. I also have phantom4 std , which only gets 6644 metres in same flight path. Both of these I use a $10- range extender purchased on Ebay. I saw on you tube someone claiming 4200 metres as world record distance for Spark so I was hell bent on breaking it and did so on Easter Sunday last weekend.[view_image][view_image]

The record is 5.2 KM using a reflector.

FCC output 0.5W
CE output 0.025W

You can see why FCC is so much better. DJI controller can be modded to output 1.5W but it's illegal unless you have a HAM radio license.
The frequency can also be changed to 2.33 or 2.57 ghz using the ISM/LIPD band.

I better get more in this weekend then I have another 550 metres to achieve!  

Like your video interesting that I notice our speeds were similar there and back but I didn't make it back had still 971 metres to go? but you got an extra 550 metres and made it back. so as you said 10 km total return 1400 metres more on same battery? But my video time was 14 minutes and 100 % power all the way you must have got nearly 18 -20 minutes out battery? which DJI claim only 16 minutes flight time?

I notice you were not recording does this make a big difference to flight time battery wise? other than that our times I notice were similar at 5km you had around 60% left same as me but I didn't get back?

BTW i noticed you were at only 50 metres height but I was at 120metres because i was informed that height is your friend for long range receiption I guess I might have chewed up some extra battery gaining this extra height and also coming down. On reflection of my video although I wasn't against the wind there and back I did have a 5 - 10 km south easterly wind off the ocean so also might have affected my battery?

your thoughts?

This thread is very informative. Gonna have the parabolic reflectors to boost my range here in PH

dw goldengrove Posted at 2018-4-4 01:37
I am in Australia and 5.8 seems to work fine. I use OTG cable on my spark  I just got an amazing 4633 metres in distance (8664 RETURN)  yes thats right. I also have phantom4 std , which only gets 6644 metres in same flight path. Both of these I use a $10- range extender purchased on Ebay. I saw on you tube someone claiming 4200 metres as world record distance for Spark so I was hell bent on breaking it and did so on Easter Sunday last weekend.[view_image][view_image]

But you didn't make it back... Spark battery range is shorter than signal range.... unless.....

El Diablo Posted at 2017-10-4 05:58
The 5.8ghz bands the Spark uses are not widely supported in EU (big mistake from their part, someone didn't do his homework). They obviously chose those because they are less 'busy'. 2.4ghz has more traffic but in EU it is the only option... The Spark is programmed to switch frecuences automatically in order to keep the best possible signal, unfortunately Dji got the exact opposite effect. if you live in heavily populated areas be prepared to loose your drone if not on the 2.4ghz channels and even so, i would rather use an OTG cable that stabilizes the connection although it is not officialy supported by Dji and voids the warranty.

ps. the Spark doesn't use the more expensive occusync system of the Mavic, instead they opted for this wifi connection. In countries outside EU the stability is widely increased.

I don’t understand how using OTG cable stableizes the connections...

Your only talking about the connection from remote to phone which is right next to each other, I’ve never used OTG and never had an issue

dw goldengrove Posted at 2018-4-5 14:16
I better get more in this weekend then I have another 550 metres to achieve!  

Like your video interesting that I notice our speeds were similar there and back but I didn't make it back had still 971 metres to go? but you got an extra 550 metres and made it back. so as you said 10 km total return 1400 metres more on same battery? But my video time was 14 minutes and 100 % power all the way you must have got nearly 18 -20 minutes out battery? which DJI claim only 16 minutes flight time?

Yes, you've picked it, how could they be getting the flight times to cover that distance at those speeds? I won't tell you directly, but I'll give you a hint and see if you can work it out.... and its not dual batteries. Read up about the difference between a Bebop 2 and a Bebop 2 Power. Parrot use the same trick to get longer flight times from essentially the same battery.
Good luck, and don't do anything dangerous. ;)

Jetline737 Posted at 2017-10-5 06:17
I ended up in this Thread because I was having the same question about 2.4GHz or 5.8GHz.
So far I have been using the default channel 149 at 5.8GHz, with signal loss at 300m even in open spaces.
Today I kept my Spark in a fixed position and walked around at far distance, with and without obstacles, and definitely noticed an improvement and increase in distance capabilities if switching to 2.4GHz.

Jetliner where are you from? What part of the world?

RustyStainless Posted at 2018-4-29 04:52
Yes, you've picked it, how could they be getting the flight times to cover that distance at those speeds? I won't tell you directly, but I'll give you a hint and see if you can work it out.... and its not dual batteries. Read up about the difference between a Bebop 2 and a Bebop 2 Power. Parrot use the same trick to get longer flight times from essentially the same battery.
Good luck, and don't do anything dangerous. ;)

Don't tease me, tell me What are you referring too?

NedUK Posted at 2018-4-29 05:26
Jetliner where are you from? What part of the world?

Australia, yes we seem to have 5.8 on spark it seems Europe does not if I read correctly?

El Diablo Posted at 2017-10-4 05:58
The 5.8ghz bands the Spark uses are not widely supported in EU (big mistake from their part, someone didn't do his homework). They obviously chose those because they are less 'busy'. 2.4ghz has more traffic but in EU it is the only option... The Spark is programmed to switch frecuences automatically in order to keep the best possible signal, unfortunately Dji got the exact opposite effect. if you live in heavily populated areas be prepared to loose your drone if not on the 2.4ghz channels and even so, i would rather use an OTG cable that stabilizes the connection although it is not officialy supported by Dji and voids the warranty.

ps. the Spark doesn't use the more expensive occusync system of the Mavic, instead they opted for this wifi connection. In countries outside EU the stability is widely increased.

ya too bad the spark didn't come with ocusync

NedUK Posted at 2018-4-29 04:46
I don’t understand how using OTG cable stableizes the connections...

Your only talking about the connection from remote to phone which is right next to each other, I’ve never used OTG and never had an issue

I think so:
 
If you do not use OTG, there are two parallel radio streams: RC <---> telephone and RC <----> Spark.
If you are using OTG, then the stream is in the wire, so there is only one radio stream: RC <----> Spark
So there is less interference.

Does anyone know why, when switched to auto, it always chooses a 5.8GHz band? And on 5.8 I find the connection drops all the time.

I want to use 2.4 but the only way to do so is to switch from auto to custom. If I do that I *have* to choose a 2.4 band, and sometimes I make a bad choice and keep losing the connection. You can't switch bands manually mid-flight, can you? When I do pick a good band, however, it works well and I can go some distance, keep connected long enough to take a sphere, and just generally enjoy a stable connection of the kind I imagine users in the US get all the time.

TL;DR: Why can't the DJI Go app auto-select a 2.4GHz band?

(I'm in the Netherlands, using iOS)

5.8 is, at first, in most location worldwide still the band with the least interferences.
Most wifis are in 2.4 Ghz
In Europe (CE), unluckily, that avantages with no/few other 5.8 wifis is gone after about 100m
In FCC however, 5.8 has even the stronger signal poweroutput.

Have you tried to fly with a otg cable?
This way you give Spark and RC the option, to switch bands midair if needed.