Alta 8 PPM erroneous readings with Dragonlink

Discussion in 'ALTA 8' started by John Santry, Nov 1, 2016.

  1. John Santry

    John Santry New Member

    Joined:
    Oct 1, 2015
    Messages:
    13
    Likes Received:
    0
    Hello all,

    We installed a V3 Dragon Link on Alta 8 and we're getting some erroneous visual readings in the Radio Mapper once its all hooked up and configured. Videos attached. From reading the manual, I understand that the Synapse midpoint is 1500ms, full up/fwd deflection is 2000ms, and back/down is 1000ms. I adjusted subtrims to get center points as close to 1500 as possible, and then we set end points to ensure servo travel was hitting the 2000/1000 mark. Actual values are more like ~2009 and ~992 when fully deflected. But they rapidly fluctuate when held at the extreme point by a few micro seconds. ie if you hold a full throttle command the ms jumps around faster than you can really read , and the numbers range from like 2002-2009. Same thing happens in neutral... the number jumps around by a few ms at 1500. The visual indication from the Radio Mapper even shows erratic deflections into other modes. We haven't flown with Dragonlink yet because I want to understand this issue before we go up in the air. Any insight or help would be greatly appreciated. Wondering if this is just a normal read out for PPM systems do to the information relay or something.

    Normal Alta 8 operation with Futaba connected


    Same Alta 8 aircraft with Dragonlink V3 Connected
     
  2. Jason Toth

    Jason Toth Active Member

    Joined:
    May 11, 2013
    Messages:
    304
    Likes Received:
    45
    Update your dlink to the latest firmware. Go into the dlink app and change the channel output to Sbus (on channel 8 for example). The dlink will now act just like your sbus futaba :) Also note you might want make sure the dlink is in V2 protocol and unmodulated.
     
  3. NickB

    NickB New Member

    Joined:
    Nov 24, 2018
    Messages:
    1
    Likes Received:
    0
    I was able to get a stable connection with a dragon link v3 slim unit. Futaba 14SG, DL receiver and Synapse set to PPM. I had to play with the receiver baud. It’s currently set at 9600 and seems to be stable with Synapse. Pin 8 on the DL receiver seems to work better for some reason so use that one for your PPM output.

    There was an issue getting the motors to initialize but I was able to fix the problem by increasing the travel of the yaw (channel 4) from 100 to 110% in the Futaba function menu. This seemed to push the dragon link signal far enough to get a good arm and motor power on.
     

Share This Page