The concept is very simple: more channels more probability to have a free frequency (channel) to use. Spectrum analyzer can't explain nothing more than this. Wifi ch 14 is not used in the U.S. so DJI channel above 20 are more suited for p3 control.
More channels hack
- Thread starter tomtnt
- Start date
The concept is very simple: more channels more probability to have a free frequency (channel) to use. Spectrum analyzer can't explain nothing more than this. Wifi ch 14 is not used in the U.S. so DJI channel above 20 are more suited for p3 control.
ianwood
Taco Wrangler
More channels only means the center frequency is more likely to be clear but doesn't prevent overlap with competing signals as the channel width is the same. And if it is truly better, why did DJI change it? They did it on the standalone Lightbridge as well.
ianwood
Taco Wrangler
Speaking to the resonant range of the antenna..................... the range of frequencies is so small, I doubt the SWR is even effected at all. Who wants to post up a graph of the swr range on the antenna over the used frequencies?
ianwood
Taco Wrangler
Missed this. So DJI's radios are bleeding over into adjacent spectrum. That could have been avoided.
The "hack" didn't add any channels. All those channels were there and available when I received my P3 a week or 2 after it started shipping.
Remember the fuss around here when an app release (don't remember which one) limited us to only 8 channels? That was probably done because some government agency, somewhere, squawked about the use of frequencies outside the wifi range. Remember also that, at the time, Dji was saying it was because of "international" regulations. Nobody even said at the time that U.S. regulations were the reason.
Obviously somebody left themselves a back door to get access to those frequencies and, just as obviously, somebody leaked it. Look at the date of the file - more than 2 months ago. I think that's about when the 24 channels disappeared.
Anyway, the "hack" is not creating any new channels or access to a wider spectrum. It just gets around a restriction that was imposed on us after we bought our Phantoms.
Ahah... At 2.4ghz you have 100mhz wideband of resonance. The pcb antenna has always a capacity hat, that compensate the Xc of the resonance itself. This is done to not overload the under dimensioned power amp of the small chips.
No, I looked, and the used frequencies do not enter into the 13cm amateur band. It was just a comment someone posted before researching it.
ianwood
Taco Wrangler
This is where the spectrum analyzer would help. Anyway, it makes sense if they limited it to the center 8 channels that there's a reason they're avoiding the outer spectrum. Bleeding into adjacent spectrum would be a logical reason.
Barring someone doing a spectrum analysis, I wouldn't assume that the frequencies of the additional channels are contiguous with the WiFi range.
Here's a seat-of-the-pants spectrum analysis of what my WiFi router is doing while streaming a Netflix movie to my Roku on WiFi channel 11:
Notice that there is zero overlap to channel 21. Makes it likely that Dji's channel 21 frequency isn't right next door to it's channel 20.
Here's a seat-of-the-pants spectrum analysis of what my WiFi router is doing while streaming a Netflix movie to my Roku on WiFi channel 11:
Notice that there is zero overlap to channel 21. Makes it likely that Dji's channel 21 frequency isn't right next door to it's channel 20.
This question keeps coming up but the answer is obvious. Add the config and connect to your bird and fire it up. Look at the traffic on the new channels compared to the original 8. If they have less traffic, then they will work better for you. Why do you care how it's sliced? Better is better!
But not at the expense of other users of the spectrum. I think that's what some of us are getting at. There are regulations in place that made DJI remove the extra channels, in all probability. We just don't know the specifics, and until I do, I'll continue using the hack. If I'm shown to be using it unlawfully, I'll remove it............. Why do you care how it's sliced? Better is better!
I added the file to my iPad and. Ow I can see all 32 channels BUT I can't select custom. Anybody a fix?
Cheers
Cheers
Not exactly sure what you mean by this. The antenna is only resonant at one spot. How far you can go off frequency before there is a mismatch I don't know. I normally don't play with stuff this high up. A typical antenna for me is usually about 100' and some even 250'!!!
I may model a vertical at 2.4 on my modeling software just to see how it acts across 2.4. You would think it would be fine. As I said I saw a post showing db loss of a 3dr solo antenna at both ends of band. Just doesn't seem right and his results are suspect to me.
Thanks for help guys.
