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Unstable channels

Discussion in 'Inspire 1 Discussion' started by worldsoutro, Jul 18, 2015.

  1. worldsoutro

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    Weird thing happened to me today. I started going through my pre flight check list and I noticed my video signal came up with a warning that said weak(electromagnetic interference may be occurring). It switched then back to a good status and stayed there for a few minutes then I saw the warning pop[ up again then disappeared. I then went to check the stability of the channels and 17 was mostly unstable and the others were good. Then for a few seconds three more channels went red(unstable) and stayed like that for 5 seconds then went back to stable. I saw this repeat.

    I then checked the IMU and all were within range. I decided not to fly because it is my responsibility to make sure everything is 100%. I wanted to research this issue before flying again. I have flown here before and never noticed any issues
     
  2. The Editor

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    Where were you (going to be) flying?
    What you describe is very common for domestic router activity. Could that be the case?
     
  3. sirnikolas

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    Sounds like a strong case of interference.
    Add checking the UAV forecast to your pre-flight check list if it isn't in there already.

    http://www.uavforecast.com
     
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  4. worldsoutro

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    Now that you said that, I had my phone at as a mobile hot spot. I also had my smart watch on connected via Bluetooth
     
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  5. The Editor

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    Me thinks, the mystery might be solved! :p
     
  6. sirnikolas

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    *throws a Corona Ed's way*
     
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  7. m00se

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    Is the I1 really that susceptible to wifi?
    Surely that renders it useless in terms of reliability these days, there's wifi and other such signals almost everywhere
     
  8. The Editor

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    Not saying the I1 is any more susceptible or immune from RF interference, the OP said the 'spectrum analyzer' was showing busy 2.4ghz traffic (which means it was doing its job) and he OP elected not to fly. And don't forget Bluetooth is 2.4ghz channel hopping technology with channel changing happening up to 1600 times a second :eek:.
    Personally, I believe that was a sensible desicion as I put everything into airplane mode before I fire up anything Inspire(ish).
     
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  9. m00se

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    I agree he made the right choice if he doubted. But I have had all except the last channel in the red, put it on the last channel manually and found no particular problems other than a shade of lag, which I now know is heat related.

    Have there been reports of people entering a WIFI hot spot whilst flying and then having problems?
     
  10. huppe

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    Wonder what App you're using.Since I switched back to 1.0.10 everything went great.Also tested 1.0.7 and 1.0.6 and everything was ok.I will not using any other app 'till this is solved.
     
  11. The Editor

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    Not that I have heard directly no (there are always hearsay stories) but I have also never heard of cellular phones causing issues on airlines BUT they are still forbidden on long haul/transatlantic flights for fear they MAY interfere with equipment.
    They at also prohibited in ICU areas of hospital but again I have never heard of anyone flat lining because a visitor texted their Mum!
    Its all preventative risk limitation.
     
  12. mdomeny

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    i flew on wifi hotspot last thursday and had no problems at all... even my damn lnding gear is working again after i switched batteries... meanwhile buying a second bird because taking off from hand and landing in a forest like shooting area was to risky for me to do the job so i had to get me a asecond backup bird...
     
  13. m00se

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    thats true, but those are relatively controllable risks, when we fly a multi rotor, we have no idea what the RF interference will be a couple of 100 m away, If it is really that susceptible to WIFI then I would say its as good as useless
     
  14. m00se

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    does the app version affect the output of the channel scanner?
     
  15. The Editor

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    That's it then......I'm not flying ever again :p.
    I think the risk is greater by having close proximity RF devices on your person and therefore close to the Inspire transmitter and receiver. Receiver front ends can easily get swamped by close proximity RF radiation not even on the same frequency. The receivers AGC circuit detects a very strong signal and throttles back the sensitivity. This can then actually deafen it to the true frequency (The Inspires) it should be listening out for.
    I'm just a chicken, cowardly, risk adverse scared nervous, terrified, trembling, quivering wreck of a flyer who likes to take as much 'uncontrollable' risk out of my flying equation as possible. :)
     
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  16. m00se

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    lol. I always try to minimise risk, but the other day I was asked to fly in close proximity to a cell phone tower, with 100w of 900mhz power, I can tell you that I got a few "weak signal" messages, but really nothing that resulted in any drift.

    saying that, I got blown off course with the wind on one occasion, but it was VERY windy, I had assumed it was wind. Maybe I got a small GPS glitch that the app didnt let me know about, I was at least 20m away when that happened though. I had been flying at about 5m
     
  17. Mark C

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    Interesting discussion.
    I have just got a spectrum analyser which is needed to obtain my RPAS permissions.
    Iam trying to work out how to analyse the results.
    Mine covers the 2.4gHz range for here in the UK.
    I turn on the analyser and then are shown the peaks of activity across the 2.4gHz range in the immediate area. So in a built up area lots of action.
    How do I check that the RPAS is not going to encounter spectrum fratricide?
    Do I then turn on the inspire and see where my "peak" is in relation to other traffic and if so how do I then interpret the results?
    Under what circumstances after doing a sweep would you consider it to risky to fly?

    thanks