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Any way to tell if there's interference on the 2.4ghz signal?

Discussion in 'Inspire 1 Help' started by Primo_NYC, Jul 3, 2015.

  1. Primo_NYC

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    Is there a detector that can tell if there's interference?
    It wasn't with my i1, but I have a Movi M15 gimbal that uses a Futaba 2.4 tx / rx setup and yesterday on a shoot they were having issues with the connection.
    I didn't think much about it, until later in the day,
    There was also a 12 rotor UAV flying the RED cam for the shoot and it went down.
    They took off, got up to about 35' and the motors just lowered rpm.
    Pilot was fighting with it, but lost the battle, he felt he lost signal with the bird.
    I wasn't there, my tech was out with the M15 and I didn't see any of this, just got it 2nd hand.
    Wondering if there's a meter that can monitor how much interference we might encounter?
    I found these, but not sure if they'll do what I need, seem more like ways to find bad stuff around the house
    http://www.lessemf.com/rf.html
    Any help will be greatly appreciated, as always
     
  2. offtosleep

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    What was the damage on the bird that went down? I bet the pilot was crying! That's an expensive rig I'm sure.
     
  3. Kilrah

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  4. Primo_NYC

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    Again, I didn't see it

    Was told most likely a complete loss, AF was in 3 pieces & gimbal in 2
    Camera body seems to be recoverable
     
  5. Primo_NYC

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    Thanks
    seems like a similar product as the lessemf ones?
     
  6. Kilrah

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    The lessemf devices will give you a single reading of how much RF is being sent as average in their entire wide sensitivity range, without saying where it is or how it's distributed. For example the model that is sensitive between 800MHz and 2.5GHz might give you a crazy high reading due to a mobile phone transmitting on 900MHz nearby while the 2.4GHz band is perfectly quiet (which it never is, but thats another story).

    The RF Explorer is a true spectrum analyzer, which will give you a plot of the signal level vs frequency. You could liken that to a thousand lessemf devices each having a very narrow sensitivity band and of which you collect the respective readings.
     
  7. Primo_NYC

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    Thank you, I have a lot to learn
     
  8. Scotflieger

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    All RPA pilots should consider having a handheld 2.4GHz spectrum analyser like the RF Explorer 24G. This inexpensive device allows the user to identify any possible interference that could affect the main I1 command and control (C2) and Lightbridge video link especially if operating in a densely populated area.

    I have mine programmed to cover the entire I1 frequency range:

    Centre Frequency = 2441.500 MHz
    Frequency Span = 85.000 MHz
    Start Frequency = 2399.000 MHz
    End Frequency = 2484.000 MHz

    You should be concerned if the maximum ambient signal noise is greater than -45 to -60dBm between 2400.000 and 2483.000 GHz.
     
  9. Primo_NYC

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    Thank you & Kilrah for the help
    I have one on it's way now.
     
  10. Ralph thompson

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    Scot, I saw you had commented on potential RC Inspire 1 Pro interference.
    I have a contract to do aerial photography in a stadium, just before the game. Potentially 20K people in the stands all flashing their smart phones around. I have to get Transport Canada approval which should not be too difficult. But being an ex pilot and super cautious, I asked DJI if the proximity of thousands of cell phones or other devices could interfere with the I1 control system. Their response was " ....... mobile cell phones in the stadium may interfere the signal bond between your remote controller and aircraft........". This makes me nervous, last thing I need is the I1 flying off into the wild blue yonder or smashing into the crowd. Any thoughts precautions, safe guards etc? I assume that the worst that could happen is that if the link was broken, the bird would just RTH? I see the RF Explorer Combo covers 2.4GHz & 5.6GHz. If you get > -45 to -60dBm does that me you don't fly? Would appreciate your or others thoughts. In 5 years of droning I've never had a problem but would not like to have it with in front of 20K people. Thanks
     
    #10 Ralph thompson, Apr 16, 2017
    Last edited: Apr 16, 2017