Anyone else seeing large battery drain on iphone?

Discussion in 'Mavic Pro Discussions' started by Stilgar, Nov 19, 2016.

  1. Stilgar

    Stilgar Member

    Joined:
    Oct 12, 2016
    Messages:
    14
    Likes Received:
    5
    Folks,
    I am seeing a 20%-30%+ battery drain per flight/battery on my iphone. This seems pretty high. Is anyone else seeing this?

    Stilgar
     
  2. The Editor

    The Editor Well-Known Member

    Joined:
    Oct 12, 2016
    Messages:
    396
    Likes Received:
    187
    I assume you have your screen on l brightness which will obviously eat away at the battery faster.
    The Go app is very processor intensive and so asks a lot of any phone however by simply ensuring you have your device in airplane mode (apart from the safety aspect of not risking harmonic rf interference) will also lower battery drain significantly not just because your device will not attempt to handshake with any cellular site but also because any apps in the background will not attempt to 'check in' from time to time.
     
  3. JakeO

    JakeO Active Member

    Joined:
    Oct 26, 2016
    Messages:
    41
    Likes Received:
    11
    I had the same problem btw with my iPhone. Ensuring before a flight you kill all background apps seems to ensure only 25-30% battery drain on my iphone 6s which is something I can live with. Prior to that I was seeing like 50-75% drain. I am not putting my phone in airplane mode for what it is worth and make sure screen brightness is not maxed.
     
  4. F6Rider

    F6Rider Well-Known Member

    Joined:
    Oct 15, 2016
    Messages:
    313
    Likes Received:
    97
    Location:
    Sunny California
    You mean RF Inductance or interference. A Signal Harmonic is signal distortion at repeated multiples of the original frequency. A perfect sine wave has no harmonic distortion, but few signals are perfect, thus causing a hetrodyne, or reflected distortion at multiples of the base frequency. This is normally not an issue in well made transmitters broadcasting the shorter wavelengths at low power. In wireless communications and broadcasting, transmitters are designed so they emit a minimum of energy at harmonic frequencies. Normally, a wireless device is intended for use at only one frequency. Signal output at harmonic frequencies can cause interference to other communications or broadcasting. For example, a broadcast signal at 90.5 MHz (in the standard FM band) would have a second harmonic at 181 MHz, a third harmonic at 271.5 MHz, a fourth harmonic at 362 MHz, and so on. Some or all of these harmonic signals could, if strong, disrupt activities in other wireless services. So harmonics would not interfere with radios on the same base frequency. When I was building transmitters in the HAM band a secondary harmonic would play hob with TV channels in the lower VHF band, getting you in trouble with the FCC.
    Sorry, couldn't help myself... long time HAM operator here :)
     
    Gary Paul likes this.
  5. The Editor

    The Editor Well-Known Member

    Joined:
    Oct 12, 2016
    Messages:
    396
    Likes Received:
    187
    The problem is we just do not know how well the DJI (Chinese) TX and RX are designed and shielded.
    A very close rf source is very capable of affecting the RX agc on the Mavic remote swamping the receiver and thus making it more deaf to distant signals emanating from the aircraft.
    My philosophy is to mitigate risk and by putting your device in airplane mode your are taking one potential problem out of the equation. :)
     
    Jengle and Theron like this.
  6. F6Rider

    F6Rider Well-Known Member

    Joined:
    Oct 15, 2016
    Messages:
    313
    Likes Received:
    97
    Location:
    Sunny California
    I agree, I was just being picky with your use of the word Harmonic, as it has no affect on the base frequency, a transmitter can put out a strong harmonic (by not being a clean sine wave) but this will only affect radios on the harmonic freq, not ones one the base freq.
     
  7. F6Rider

    F6Rider Well-Known Member

    Joined:
    Oct 15, 2016
    Messages:
    313
    Likes Received:
    97
    Location:
    Sunny California
    Have you flown any other drone with that iPhone, like the P3 or P4? Just curious if you have had the same battery drain with them. My P3 could run thru 3 batteries and my iPhone 6+ would only drop 30% for all three. Was just wondering if the Mavic was for some reason more of a drain on the phone than the Phantoms were.
     
  8. The Editor

    The Editor Well-Known Member

    Joined:
    Oct 12, 2016
    Messages:
    396
    Likes Received:
    187
    Absolutely, but can you imagine the Mavics final O/P stage is as clean as a whistle or the remotes receiver rejection and non fundamental immunity is up to a piece of Amateur Radio equipmemt? I am sure it has been through the FCC certification but I for one am not happy about a cell phone pumping out rf searching to handshake with a cell within a few centimetres of the Mavics RX
     
  9. ThreeGs

    ThreeGs Well-Known Member

    Joined:
    Oct 12, 2016
    Messages:
    72
    Likes Received:
    34
    Location:
    Western MD (Wash Co)
    Yes!!! WOW, yes!!
    My screen brightness is very low normally. I will try quitting other apps and maybe go into airplane mode next time. However, I was only using my iPhone (it's a 5s) while I was waiting on a Nexus 7 to arrive and take over as my flight screen. The Nexus 7 seems to handle battery drain a little better.


    Sent from my iPhone using MavicPilots
     
  10. F6Rider

    F6Rider Well-Known Member

    Joined:
    Oct 15, 2016
    Messages:
    313
    Likes Received:
    97
    Location:
    Sunny California
    Now you have my interest up, I will have to fire up the scope and signal generator when I get mine to see just how clean the final stage is, and check for drift.
     
  11. F6Rider

    F6Rider Well-Known Member

    Joined:
    Oct 15, 2016
    Messages:
    313
    Likes Received:
    97
    Location:
    Sunny California
    Also turn off 'Background refresh', or restrict it to when on WI-FI. This is not good news.
     
  12. Stilgar

    Stilgar Member

    Joined:
    Oct 12, 2016
    Messages:
    14
    Likes Received:
    5
    No...I fly my P3P with an ipad. I did not see this issue with the ipad. and P3P.
     
  13. Stefan350

    Stefan350 Well-Known Member

    Joined:
    Oct 16, 2016
    Messages:
    52
    Likes Received:
    6
    Location:
    North Carolina
    Using iPhone 7, no problem as it's only dropping maybe 5% per flight.
    I know from experience the iPhone battery isn't so great after the one year mark.
     
  14. F6Rider

    F6Rider Well-Known Member

    Joined:
    Oct 15, 2016
    Messages:
    313
    Likes Received:
    97
    Location:
    Sunny California
    My iPhone 6+ is over 2 years old and the battery still lasts me 3 days, and on my P3 it drops about 10% per flight with full bright and data connected, I will be curious to see how it does with the Mavic, providing of course if DJI ever ships me one.
     
  15. Fattybolatty

    Fattybolatty Member

    Joined:
    Nov 19, 2016
    Messages:
    14
    Likes Received:
    0
    IMG_0566.JPG
    This is happening on my iphone 6s plus. I have used the same phone to fly a p3 standard a p3 advanced and a p4 but none of them used the battery anywhere near as much as the mavic!
     
  16. F6Rider

    F6Rider Well-Known Member

    Joined:
    Oct 15, 2016
    Messages:
    313
    Likes Received:
    97
    Location:
    Sunny California
    That just indicates the percentile of energy used by app, not the total battery power used, I see you fuel gauge shows about 3/4 battery, was this after a flight, 2 flights, or just general usage. We know that the DJI go app uses more power than other apps, the question is how much of total battery power is used per flight by DJI GO? Charge your phone to full, make one flight then check the battery usage, that will show how much just the DJI go app used.
     
  17. Fattybolatty

    Fattybolatty Member

    Joined:
    Nov 19, 2016
    Messages:
    14
    Likes Received:
    0
    That screen grab was taken after a flight, phone was fully charged and screen brightness was just over 50%,flight was for about 15mins. batter percentage afterwards was showing 69%
    As i said i have used phone with 4 dji drones now and the usage has been negligible .
     
  18. F6Rider

    F6Rider Well-Known Member

    Joined:
    Oct 15, 2016
    Messages:
    313
    Likes Received:
    97
    Location:
    Sunny California
    WOW!, you didn't mention it was right after one flight and you started with a fully charged battery. That is crazy! How old is the iPhone? could be the battery is going south. There is no way it should use that much, something is wrong, I have flown 6 flights on my P3 and used less power than that.
     
  19. Fattybolatty

    Fattybolatty Member

    Joined:
    Nov 19, 2016
    Messages:
    14
    Likes Received:
    0
    I know, phone 1 year old full charge usually lasts 48 hrs, again as i said flown my p4 and previous p3 and no issue! something is causing it to suck the juice
     
  20. Ulfertg

    Ulfertg New Member

    Joined:
    Nov 6, 2016
    Messages:
    4
    Likes Received:
    0
    I had a battery drain issue with the DJI Go app and an iPhone 6 as well.
    The phone got very hot and the battery went from full to shut-down in less than 30 minutes.
    I did a restore of the iPhone and the issue was gone.
    Restoring an iPhone is very easy, maybe it's worth a try?
     
Loading...
Similar Threads - Anyone else seeing Forum Date
Is anyone else experiencing frequent disconnections? Mavic Pro Discussions Nov 5, 2016
Have anyone else experienced uneven focus ? Mavic Pro Discussions Oct 29, 2016
Anyone else have a snowflake Mavic they want to sell? Classifieds Oct 28, 2016
Anyone else order from Carolina Dronz? General Discussions Oct 24, 2016
Anyone mounted a Trackimo on the DJI Mavic Pro yet? General Discussions Yesterday at 9:36 PM

Share This Page