Video interference and blackout

Discussion in 'Cinestar 8' started by Chris Babiana, Apr 2, 2013.

  1. MIke Magee

    MIke Magee Active Member

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    I'm in the same boat and agree with both Josh and Brad. I've stepped back to the 1.3 lawmate for the camop and VLOS for me.
    But I will try to circle back as time allows because I have heard some success stories. Good luck Chris!.
    -m


     
    Chris Babiana likes this.
  2. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
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    You can easily see four volt noise pulses on the +5 volt supply to the servos. I think there's a lot of back-EMF coming out of the servos....

    Andy.
     
  3. Chris Babiana

    Chris Babiana Member

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    Thanks everyone for your input!
    I've spent waaay to much $$$ on this system for it to be a dud! My upgrades will arrive Friday (so the tracking says) or Saturday and I'll post my results. For now, back to that dang roll radian tweaking! Does it ever end??? And I thought owning a boat was a hassle! o_O
     
  4. Josh Lambeth

    Josh Lambeth Well-Known Member

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    Maybe ill try this as well... figured since I am using a BEC it was cleaning some of that EMF noise out... guess I was wrong? Ill try a separate battery and see what happens.

    Josh
     
  5. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
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    Hi Josh:

    I've forgotten your setup - do you have the Bluebeam antenna pointing upwards, or is it you that has the "auto-extend" mechanism on one of the landing gear for the antenna and it's pointing downwards?

    Andy.
     
  6. Gary Haynes

    Gary Haynes Administrator
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  7. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
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    I'm not an antenna guru (or any other kind of guru, come to think of it), but I know that Bluebeam antennae are right hand circular polarized.

    What I don't know is whether that polarization is "right hand" look at the electric field emanating from the transmitter or from the receiver -- there is a classical historical disagreement as to which you use to determine the left/right handedness -- and it matters because right hand from the Tx point of view is left hand from the Rx point of view.

    Also what I don't know is whether, if you invert the Bluebeam transmitter antenna, you must also invert the receiver antenna. The guy who makes them, IBCrazy, seems to be active on rcgroups.com, so maybe I should ask him...

    Andy
     
  8. Brad Meier

    Brad Meier Active Member
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    I don't think that would make much of a difference. It's seems, with 5.8 at least, that having a separate battery to keep a clean source to the transmitter greatly affects the quality. I'm fine with my 1.2 but I've never had it further than 250-300 yds.
     
  9. Gary Haynes

    Gary Haynes Administrator
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    My TX antenna points down and the Recv points up. At 1.5 miles had a good video feed. Don't think that up or down matters.
     
  10. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
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    Good. That answers that question. I know with a whip antenna most of the radiated power is transmitted in a flattish circle from around the tip and at 90 degrees to the whip's long axis, so you need the Tx and Rx antenna to be pointing vertically up or down...

    Andy.
     
  11. Chris Babiana

    Chris Babiana Member

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    The "Gary Haynes" knockoff. Nice idea Gary!
    photo-2.JPG
     
  12. Gary Haynes

    Gary Haynes Administrator
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    Let us know if it improves your video reception.
     
  13. Chris Babiana

    Chris Babiana Member

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    So everything is installed but I still get unacceptable dropout. (both on the CS-8 with 5.8 and my NAZA F450 with it's own 5.8) I have the ground station from Quadrocopter with the Pyle monitor and a second monitor, a Marshall M-CT7. I never had an issue with the Marshall using it as an on camera monitor. With the 5.8 down-link? Forget it!
    http://www.bhphotovideo.com/c/produ...s_m_ct7e_M_CT7_Portable_Camera_Top_Field.html
    About to pull my hair out, I remember having a 7" $50.00 Wall-mart special portable LCD TV I bought in a pinch 4 years ago. I hooked it all up and NO DROPOUT.
    I've read posts here about what others are using for monitors (successfully) and some use both the Marshall and the Pyle. Is the 5.8 somehow interfering with the monitors? Getting a bit tired of blowing cash to attain the right combo. Using the cheap-o is not an option, battery life is only 2 hours (internal battery).
    I've thrown my hands up on this one...severely frustrated and clueless! Other than starting to think the 5.8 is not the way to go.
     
  14. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
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    I think the difference tends to be the degree to which the monitor demands a sync signal -- and it sounds like the Marshall is more demanding than the cheapy TV. I've noticed that digital monitors will blue screen when the sync signal breaks up, but the more analog monitors (typically the cheapy ones) will hold on to the signal even if it briefly turns to snow.

    I realize that this doesn't help you much, Chris.

    What I've seen some folks do is to interpose a DVR with video passthrough between the receiver and the monitor. The DVR has the effect of regenerating the sync so that the digital monitor doesn't blue-screen.

    Are you seeing actual blue screens or just video breakup?

    Apologies if you've already answered this, but are you powering the Video Tx off a BEC to give it good clean power?

    Andy.
     
  15. Chris Babiana

    Chris Babiana Member

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    Thanks Andy. It's like this...when you buy a new car right off the lot, and pay a handsome price for it, you EXPECT it to work...period. Not spend your nights and weekends turning wrenches and blooding knuckles on an investment you barely used...and keep dumping cash into for upgrades with hopes of video bliss!
    I understand your explanation about the digital sync (yes, I'm getting the blue screen...constantly), but it seems that others are having success with this same set up. And after the investment of the Bluebeams, I wasn't expecting signal drops. I read a few comments about the FOXTECH FPV Monitors...not too expensive, maybe I'll try one.
    The BEC...I didn't try it yet, I'll connect it tomorrow....
     
  16. Gary Haynes

    Gary Haynes Administrator
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    Chris if you are running power to the Iftron from the main flight power bus try hooking itnupto a small 3s battery direct and see if youngest a difference. Also how about a photo,of the ground station setup?
     
  17. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
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    Hi Chris:
    Yeah. I hear you, man! I wish I could tell you it wasn't so, but I'd lying if I did. :(
    As someone said on the PBS Special about "drones" (ugh), "we're at the bi-plane stage of aviation...."
    Just keep posting and we'll do what we can to help! :)

    Both Gary and I are going down the thought chain of trying to figure out whether there is electrical noise on the system that's degrading the system.

    That said, the evidence is forcing me to ponder whether the issue is the transmitter. I'm using a Mondo Stinger too, but I'm using the 1,000 mW version so it's kicking out a bunch more radiated power.

    Andy
     
  18. Chris Babiana

    Chris Babiana Member

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    Hi Gary...both FPV setups are run from dedicated batteries. No connections to the main power dist. board. Ill post a photo in the morning of both.
    Andy, I would initially tend to think the same thing about the transmitter...but, on both systems? Personally, I'm leaning to the the monitors and what their lowest signal loss is...if that makes sense. Two monitors on two different systems (Pyle & Marshall) all dropping. Then, stage left....the Wall-mart $50 discontinued closeout "buy of the week" working perfectly? :cool:
    I'll introduce the BEC tomorrow and see if anything changes...:mad::mad::mad:
    Thanks guys!
     
  19. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
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    I hear you! :)
    It defies logic. Professional gear working less well that Walmart closeouts....strange but true....

    Andy.
     
  20. Brad Meier

    Brad Meier Active Member
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    Chris, I too have felt your Marshall pain. 2 years ago I bought one and promptly returned it. I'm not exactly sure what wasn't working as that was a while ago but I did replace it with an IKan and that I've never had an issue with.
     

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