More channels hack

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Thanks for this, Dome!

So, my question is like rmm's. If we accept that DJI's 32 channel spectrum within the FCC's 12 channel spectrum, then where does DJI's 8 channel spectrum fit? Is it equally distributed, meaning their 32 channel spectrum is adding a level if granularity and not necessarily range, or is it clumped at the bottom, meaning the 32 channel spectrum does add range (over the 8, not the FCC range)? Either could be of benefit, though the latter seems more so.
See the chart. The 8 channels in red are the 8 channels DJi left available. The channels in green are the ones DJi had originally made available and this mod restores.

WiFi vs DJi Channelizing Chart.jpg
 
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Again, I don't care if you show me the Declaration of Independence rrmccabe, I'm just going off of what I have experienced first hand. Maybe your on someone's payroll for downplaying the improvements ( no offense) but I and others have experienced much better range and drop out reduction from this mod period. You claim it's not possible and you show the group these charts and scope readings, I and others show you vastly improved range and lessened drop outs. Now should we just believe your data and revert back to the stock setup and assume the decreased performance that apparently you proclaim does not exist? Think about it, it it were as you say and there is no difference then why did DJI remove these channels after 1.07? Why even have them in the first place if wasn't significant? Here's more anecdotal evidence for you......MANY of us have lost range with the newer firmware updates. Check the forums yourself. The one major change has been to eliminate the extra channels for whatever the reason. Amazingly, this is when we experienced a decrease in range and reception. Now this mod comes along and most of us have improved by a LOT. So just maybe instead of taking the chalk and blackboard route, install the mod and see for yourself. It's not snake oil if many of us see and more importantly, EXPERIENCE the benefits......just my opinion.
 
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That said, I saw a recent post on another site where they took a 2.4ghz antenna and ran it on an analyzer. Of course the further you get from the resonant frequency of the antenna the more loss there is. I was honestly surprised how much loss in just the 8 channels.

So my concern is even if we are moving to quiet frequencies are we gaining enough by doing that to offset the loss by being non resonant.
I tried searching for information on this myself, and so far haven't found anything relating specifically to P3s. Could you post a link to this post? I'm curious which channel is closest to the resonant frequency of the antennas.
 
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Again, I don't care if you show me the Declaration of Independence rrmccabe, I'm just going off of what I have experienced first hand..
LOL, I am not on anyone's payroll and as I have said numerous times I am just asking the question as I don't see why it helps.

The fact it is working for you first hand means its a good mod for you. Not downplaying that at all. Just trying it out.

So don't get your panties in a bunch. You will NOT find one post where I said this mod does not work. I may be wrong in some of my assumptions but trying to figure all this out.

I am reasonably sure than DJI is not working outside the standard 802.11 range which they also have listed in their specs.

Their unorthodox number system confuses things even more.

Once again @hidaven, I never said it did not work.
 
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I have a basic frequency counter that goes up to 2.6 ghz. It's hard to get a consistent reading with 4 antennas so close together but from what I can tell each antenna is using a different frequency.
 

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According to the chart, I would expect your first screen shot to be when you had channel 5 selected on your router. Same for the second screen shot would be when your router selected channel 7.

View attachment 26867
Yeah, so the conclusion is that the mapping you illustrated is not correct. Or my router is rather strange.

WiFi channel 1 is about the same as DJI channel 13, and WiFi channel 14 is about the same as DJI channel 20.

So, this means that DJI channel 13 is at 2,412 GHz, and DJI channel 20 is at 2,484 GHz.
Assuming the DJI channels are equally distributed over the frequency range, and extrapolating DJI channel 1 to 32 from the above, gives roughly this mapping:

 
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Yeah McCabe but you were thinking it!! Lol, no qualms friend. My wife and I started having sex again because of this mod.....lol.
Great mod if if fixed your wife. Please PM me the details as I have similar issues !

I am truly curious is all guys.
 
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I am reasonably sure than DJI is not working outside the standard 802.11 range which they also have listed in their specs.
We all know they are not. Channel 13 to 20 is within the WiFi/ISM range. And ch 13 to 20 is all we got (unless someone comes up with a hack that, lets say, reconfigures their equipment... oh, wait)
 
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Stupid question, these new frequencies or use of are loaded onto the iPad or in the app itself. If the app goes down do you just loose video signal or is the RC link also affected? I'm assuming these channels are just video.
And one last question........I'm assuming that we must keep the iPad and app connected even if we want to fly with goggles? Or can you fly with goggles alone and still keep the 30 channels.
The way most variables work via the app, is to changes the variables on the P3s onboard memory. In other words, you're not simply just making changes to settings on your app that the P3 then checks in on at regular intervals, but actually sending those settings to the onboard computer. What you see on your app, is what your P3 sees in it's own memory. So, if the app goes down, nothing will change with the P3. So long as your goggles don't try assigning another channel, your P3 will continue using the same channel you set last time you had your app connected.
 
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I have a basic frequency counter that goes up to 2.6 ghz. It's hard to get a consistent reading with 4 antennas so close together but from what I can tell each antenna is using a different frequency.
That could be interesting, however, i guess you have to measure at the copter antenna since this is about the video feed FROM the copter.

So if you install the hack, select channel 1 in the app, power on the copter so you can see the video feed in the app, then you should be able to measure something around 2,3 GHz at the copter side (if my theory holds). Note that there are two antennas in the copter too, one in each leg.
 
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Yeah, so the conclusion is that the mapping you illustrated is not correct. Or my router is rather strange.

WiFi channel 1 is about the same as DJI channel 13, and WiFi channel 14 is about the same as DJI channel 20.

So, this means that DJI channel 13 is at 2,412 GHz, and DJI channel 20 is at 2,484 GHz.
Assuming the DJI channels are equally distributed over the frequency range, and extrapolating DJI channel 1 to 32 from the above, gives roughly this mapping:


According to DJi FCC report, DJi's channel 1 is 2405.376GHz, channel 19 is 2442.240 and channel 36 (not used) is 2477.056
The FCC reports also states that DJi channels are spaced 2.048MHz apart.

The chart in your post has the lower and upper DJi channels out of the band and with 10Mhz channel spacing.

Run your test using my chart and report back your findings.
 
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No, the mod has made me so happy that I now have added stamina to service my wife without having ESPN on in the background......She calls me the "phantom" now and I charge out of the closet in a Home Depot amok all 32 channels blazing.......too much info?
 
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Yeah, so the conclusion is that the mapping you illustrated is not correct. Or my router is rather strange.

WiFi channel 1 is about the same as DJI channel 13, and WiFi channel 14 is about the same as DJI channel 20.

So, this means that DJI channel 13 is at 2,412 GHz, and DJI channel 20 is at 2,484 GHz.
Assuming the DJI channels are equally distributed over the frequency range, and extrapolating DJI channel 1 to 32 from the above, gives roughly this mapping:

No, I think your router is fine and the chart your using is throwing your testing off a bit.
 

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According to DJi FCC report, DJi's channel 1 is 2405.376GHz, channel 19 is 2442.240 and channel 36 (not used) is 2477.056
The FCC reports also states that DJi channels are spaced 2.048MHz apart.

The chart in your post has the lower and upper DJi channels out of the band.

Run your test using my chart and report back your findings.
Ok, but that is exactly what I did. Or can you explain what you mean.

I did set the router to channel 1. It mapped to DJI channel 13.
I did set the router to channel 13. It mapped to DJI channel 19.

Do you have a link to the FCC document you are referring to?
And why do you assume that channel 1 in the FCC doc is the same as the DJI channel 1 in the Pilot app?
 

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No, the mod has made me so happy that I now have added stamina to service my wife without having ESPN on in the background......She calls me the "phantom" now and I charge out of the closet in a Home Depot amok all 32 channels blazing.......too much info?
Oh, the good old channel sex, stimulating all the 32 zones in parallel.
 

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Okay, you've piqued my interest. I'll reinstall it as many times as I have to.......... please, tell us more! :D
Sounds like the hack added more frequency.
 
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I tried flying known areas that I was getting lost signal on auto and channel 20 using many of the new channels (including mostly channel 32). Made no difference at all to my range. It would start RTH and when I got signal back I would change channel and go back to where I lost signal. Would lose it at about the same spot everytime. Also, transmission quality made zero difference as well.
 

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