P4 Power Output for Video is only .598 Watts v. .746 Watts on Original P3P

[kphantom]

14 microwatts difference!

This is negligible.

Definitely not significant!

 

[dewster]

Not at all. My point was about people comparing the power levels in FCC documents and thinking they know what the real world difference will be. It is far more complicated than power levels. This is not ham radio. And with SDR, DJI can and has changed power levels via firmware updates. This is a tempest in a tea cup.

Yeaaa! Sounds good!


Sent from my iPhone using PhantomPilots mobile app

 

[sar104]

Field strength is generally non-linear with transmitter power, typically going with the square root of power so, even if these asserted numbers are correct, it should only represent a 10% decrease in signal strength at any given range.

 

[GadgetGuy]

Field strength is generally non-linear with transmitter power, typically going with the square root of power so, even if these asserted numbers are correct, it should only represent a 10% decrease in signal strength at any given range.

I'll ask the same question yet again, to which I have yet to receive a meaningful response.

How else do you explain the real world numbers of a significant degradation in video stability, whenever the output power numbers from the aircraft have been lowered? Same with the successive TX power reductions.

Without a doubt, the original W323 P3P with the GL300A TX has the greatest control range and the most stable video at long range over any other P3P and the P4. The P4 uses the weakest TX of the P3 series and the P4 aircraft has a 20% power output reduction over the original W323 P3P. The P4 has the worst range and greatest video instability, when compared side by side with any P3P version.

Don't dispute the data. Just give me any other change in hardware or firmware that could explain it, if it is not solely due to the change in power outputs.

I am all ears.

 

[Kman]

Look, I love my P4. I also love my first version P3P.

As soon as I started flying the P4 I knew something was wrong. The distance is no where near what I am able to get with the P3P.

I flew 400 feet up yesterday and a few hundred feet in front of my takeoff location with the P4 and the signal was cutting in and out. Never had that issue with my P3

 

[sar104]

I'll ask the same question yet again, to which I have yet to receive a meaningful response.

How else do you explain the real world numbers of a significant degradation in video stability, whenever the output power numbers from the aircraft have been lowered? Same with the successive TX power reductions.

Without a doubt, the original W323 P3P with the GL300A TX has the greatest control range and the most stable video at long range over any other P3P and the P4. The P4 uses the weakest TX of the P3 series and the P4 aircraft has a 20% power output reduction over the original W323 P3P. The P4 has the worst range and greatest video instability, when compared side by side with any P3P version.

Don't dispute the data. Just give me any other change in hardware or firmware that could explain it, if it is not solely due to the change in power outputs.

I am all ears.

You may have misunderstood the point of my post. I was simply pointing out that the alleged reduction in power should not account for the reported reduction in range. It's just simple physics. If there are other factors in play then it is hard to deconvolve the effects.

As for explanations, amidst all the shouting I have seen few simple comparisons between a stock P3P and a P4 - at least that have clearly been stated as such. Lots of examples of pilots with Windsurfers, modified RC equipment, and such. Dirty Bird, on the other hand, appears to be getting over two miles without problems, and stated that it looked like it would match the P3 in better conditions. I haven't range tested mine, since this is poor terrain for that kind of experiment, but I think I'll wait until the hysterics have died down before drawing any conclusions.

 

[Davphys]

Does the P4 remote have he same output as the most recent P3P remote?

You may have misunderstood the point of my post. I was simply pointing out that the alleged reduction in power should not account for the reported reduction in range. It's just simple physics. If there are other factors in play then it is hard to deconvolve the effects.

As for explanations, amidst all the shouting I have seen few simple comparisons between a stock P3P and a P4 - at least that have clearly been stated as such. Lots of examples of pilots with Windsurfers, modified RC equipment, and such. Dirty Bird, on the other hand, appears to be getting over two miles without problems, and stated that it looked like it would match the P3 in better conditions. I haven't range tested mine, since this is poor terrain for that kind of experiment, but I think I'll wait until the hysterics have died down before drawing any conclusions.

 

[ringolong]

Someone did a range test and posted on Youtube,

 

[Davphys]

Out in the absolute middle of nowhere. I think the P4 is WAY more susceptible to interference than the P3 series thus in urban or suburban areas is range is dramatically reduced.

Someone did a range test and posted on Youtube,

 

[sar104]

Does the P4 remote have he same output as the most recent P3P remote?

The current specifications on the DJI website indicate 20 dbm for the P3P and 23 dbm for the P4. If that is correct then the P4 RC has twice the EIRP of the P3P RC.

 

[ringolong]

Out in the absolute middle of nowhere

lol!!! I was thinking this poor guy has nothing exciting to film from the looks of it.

 

[sar104]

Out in the absolute middle of nowhere. I think the P4 is WAY more susceptible to interference than the P3 series thus in urban or suburban areas is range is dramatically reduced.

You think that why, exactly?

 

[Davphys]

Because there seems no other way to explain the lower range vs P3P that people are getting in urban/suburban areas.

I have a feeling that if enough people email Frank Wang: [email protected] then we will see a swift firmware update that will fix a lot of these problems.

You think that why, exactly?

 

[sar104]

Because there seems no other way to explain the lower range vs P3P that people are getting in urban/suburban areas.

I have a feeling that if enough people email Frank Wang: [email protected] then we will see a swift firmware update that will fix a lot of these problems.

So now it is an interference issue, not power output? This all seems like random guesswork based on flimsy anecdotal evidence. I would hold off with the complaints and lawsuits until someone has managed to do something resembling controlled testing that confirms a range problem.

 

[Davphys]

It is anecdotal right now- you are right. But the RC power output is specified as the same yet the bird gets less distance. I don't think is coincidence that something is going on here.

People are now doing controlled flights and it appears the distance is reduced versus the P3P. I myself tested both in my area and the signal was cutting out on my P4 at a MUCH shorter range than my late model P3P.

So now it is an interference issue, not power output? This all seems like random guesswork based on flimsy anecdotal evidence. I would hold off with the complaints and lawsuits until someone has managed to do something resembling controlled testing that confirms a range problem.

 

[sar104]

It is anecdotal right now- you are right. But the RC power output is specified as the same yet the bird gets less distance. I don't think is coincidence that something is going on here.

People are now doing controlled flights and it appears the distance is reduced versus the P3P. I myself tested both in my area and the signal was cutting out on my P4 at a MUCH shorter range than my late model P3P.

Your late-model, stock P3P, with stock RC? Just checking.

 

[Davphys]

Yes. Late model stock P3

Your late-model, stock P3P, with stock RC? Just checking.

 

[sar104]

Yes. Late model stock P3

Perhaps you posted and I missed it - what are the ranges you are getting with the two models? And at the limit are you losing control, video, or both?

 

[Davphys]

I start losing both control AND video at about 3000-3500 ft in my urban congested area with the P3P and with the P4 I lose BOTH at about 2000 ft of distance. Same area, same conditions.

Reading the boards others are noticing this same pattern.

 

[GadgetGuy]

You may have misunderstood the point of my post. I was simply pointing out that the alleged reduction in power should not account for the reported reduction in range. It's just simple physics. If there are other factors in play then it is hard to deconvolve the effects.

As for explanations, amidst all the shouting I have seen few simple comparisons between a stock P3P and a P4 - at least that have clearly been stated as such. Lots of examples of pilots with Windsurfers, modified RC equipment, and such. Dirty Bird, on the other hand, appears to be getting over two miles without problems, and stated that it looked like it would match the P3 in better conditions. I haven't range tested mine, since this is poor terrain for that kind of experiment, but I think I'll wait until the hysterics have died down before drawing any conclusions.

I'm inclined to agree with you. However, it appears that the power reductions do correspond with the reductions in control and video range. The P4 performance, however, is even worse than the power reductions alone would indicate, assuming the reductions were linear. I only care about results. I know which aircraft and which mods perform the best and which are mediocre, and which are terrible. P4 out of the box is the worst, compared to all versions of the P3P. I am hoping my mods can help overcome that. We definitely will also need a battery mod! Might even need a birdside video amp, or even just a better birdside video antenna that will unfortunately interfere with the clean Apple Look.