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Moving the potentiometer?

Discussion in 'General Discussion' started by cosmonaut, Jul 5, 2014.

  1. cosmonaut

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    So I moved the potentiometer from the board to the front using a 5k. It works fine turn right it pans down, left pans up. BUT when I turn it all the way to the left the transmitter beeps and dies sending the drone into come home mode. As long as I watch myself and don't turn it all the way I do fine and even if I move it all the way left I have a second or two to correct it before the drone starts coming in. But at that I would like to fix it. First do I have something wired wrong? A bad pot? Or do I need to add some resistance to the pot?
    Suggestions welcome......
     
  2. Happyflyer

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    Start by double checking your wiring. Other than that, the experts here can help better than I can.
     
  3. cosmonaut

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    Thanks I will do that.
     
  4. KimBrown

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    Use a 1k ohm resistor in series with the wiper connection.
     
  5. MrC

    MrC

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    Is that the center connection on most pots?

    +op, what exact pot are you using? I'm about to do the mod and will avoid that pot if possible. Thanks.
     
  6. KimBrown

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    It sounds like your driving the transmitter outside of it's comfort zone when the pot is at it's extream position.
    As I said earlier, 5k for the pot is normal, but most times the makers have a 1k resistor in series at both ends of the Pot so the minimum and maximum still sees 1k and not a direct short. If your system works ok except at the limits, then putting a single 1k ohm resistor in series with the wiper will achieve the same thing. Normaly the wiper is the center connection, but you can soon check it with a multimeter.
     
  7. cosmonaut

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    Thanks I will try that and see how it goes. I will get back after I do.
     
  8. MrC

    MrC

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    Please do :) My pot is in the mail. Very interested if this fixes it for you.

    So a 1k resistor in line with wiper. I saw another post where they recommended 100ohm resistors in line with the two outside connections, would this work too?
     
  9. KimBrown

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    Yes, I suggested a 1k off the top of my head. If they found two 100 ohm resistors worked then a single 200 ohm would.
    Its when the wiper gets to the extreams. It could be doing two things without the resistor.
    1) Over driving the circuit and taking it out of it's working zone.
    2) Shorting out the circuit, and the whole transmitter.
    I suspect 1 is more likely... I had a similar puzzle on a Hi-Tec radio I was using, then realised what I was doing...
    I haven't my Phantom here with me onboard the ship else I'd look at the circuit.
    At the end of the day either method lets the transmitter see a resistance it can work with. I wouldn't fly it till you've tested it on the ground thou first after doing the mod. If it was me, I think I'd remove the existing Pot, solder wires into the board and run them as three twisted wires to the new pot... I take it you are disconnecting the existing pot, cos you can't have the two wired together....
     
  10. cosmonaut

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    Yes the old pot is removed and wires ran to the new one. I am picking up some resistors today and I will try the 100 ohm. Yes I will try it on the ground before in flight. I did do a lot of flying this weekend with it as is I just didn't mess with the gimbal pot much and sort of left it as is during the flights.
     
  11. MrC

    MrC

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    Ok, they mentioned 100ohm but that too was off the top of their head, they hadn't tested it.
    Not sure which way to go really, - 1k on the wiper, 200ohm on wiper, 1k on two outer legs, 100ohm on 2 outer legs, some other amount ie 300 ohm on 2 outer legs...

    Some people are fine with just a 5k lin pot and no resistors, others have bricked their remotes with exact same setups, not always straight away either. It's not the end of the world if the remote breaks, more worried about the rth that would be initiated if it failed in the field.

    hmm, decisions...
     
  12. Paul K

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    I had exactly same experience today when i turned the knob I noticed the yellow light and it started to move ,I quickly flipped to ATTI and back to GPS and than it was flying ok . I tried to turn the knob few more times and the same happened once again.
     
  13. MrC

    MrC

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    Which pot are you using Paul?
     
  14. Paul K

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    Actually I have two of them on my P1 I have 5k radio shack for some time with no problem ;but I just wanted to innovate little bit and on my P2 I installed 3.5 mm stereo jack and in separate box I installed 5k pot from local electronic store ( my intention is to connect pot with short stereo cable and lock the pot in separate box to my radio for one person control ,but if I use 6 ft cable ,the person who will be helping with video can control the gimbal roll ).I tried it several times with long and short cable and never had problem (today it hapend first time). The radio shack pot was installed inside P1 radio with no problem . I did remove the pot from P1 radio and installed 3.5 stereo connector as well , now I will try to switch both pots back and fort on P1 and P2 and see if both will cost the same problem or if it is only the pot from my local store
     
  15. cosmonaut

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    UPDATE: It seems the 100 ohm resistor on the wiper works. After the install I tested it for a long time and it seems fine. I have a Tarot Gimbal and also set it up some with the software so I have more than enough testing with it. Thanks for all of the help.
     
  16. MrC

    MrC

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    100 ohm or 1k ohm? Sounds good.
     
  17. cosmonaut

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    100 ohm
     
  18. DKDarkness

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    M'kay... I'm successfully using a 100Kohm linear pot... used a german instructional video: http://youtu.be/XTUSqNtt7bM?t=2m