Welcome to PhantomPilots.com

Sign up for a weekly email of the latest drone news & information

P2V+ centered tilt slider for v3.08 firmware

Discussion in 'Firmware' started by ElGuano, Nov 27, 2014.

  1. ElGuano

    Joined:
    Sep 4, 2013
    Messages:
    2,219
    Likes Received:
    4
    With DJI giving us the 7th channel gimbal tilt control in firmware v3.08, we now have three choices:

    1. Buy the new controller with the tilt wheel. $100.
    2. Buy the Phantom / P2 gimbal tilt lever. It's $15, but you have to center the lever precisely to stop the gimbal from slowly tilting.
    3. Install a knob or slider pot with a center detent, so you have tactile feedback when the gimbal is stopped. $1.50. That's what we're going to do here!

    First, you need a pot. It should be 5K ohm resistance, linear taper, 20% tolerance. If you're using a slider, I think 20mm travel is just about perfect. I have a bunch of these from Mouser.com, but they seem to be discontinued now. No worries, plenty of alternatives are still available.
    [​IMG]

    Next, I opened up the TX, and positioned the pot. I like it having it on the right hand side, but it fits on the left just as well.
    [​IMG]


    Testing the LED - the wires are reversed in this picture, but it lights up with 3.5v power. I don't really care for an LED on the pot sucking up batteries, but since it came with em, might as well wire it up, right?
    [​IMG]

    Most tutorials tell you to remove the existing pot. You really don't need to do so. I just solder the new pot to the old pot's pins on the backside of the PCB. The next pic shows the TX's circuit board removed and flipped over. The pot and connections are on the bottom right, the left side is where I tapped 3.5v power for the LED
    [​IMG]

    Here's the pinout for the potentiometer. You need to look at the data sheet for the pot you use, but it will usually be labeled with 1/2/3, for ground, wiper and output. The colors for the text correspond with the wiring and the connection to the circuit board in the previous picture.
    [​IMG]

    Now's a good time to test the connection. Use a multimeter with probes connected to 2 and 3. If you slide the pot all the way in one direction, it should go to about 3.5v. Slide it all the other, it should go to 0v. Taper should be linear (stopping the pot at the center detent should be about 1.75v). Don't forget to zero out the DJI stock pot on the other side.

    With the electronics done, all you need to do is drill a hole for your knob, or carve out a slot for your slider to fit:
    [​IMG]

    Fitting and securing the pot (I just glob a ton of hot glue to keep it affixed):
    [​IMG]

    Installation complete. Remember to zero out the old pot! Full clockwise.
    [​IMG]

    Finished and closed back up. Don't forget to calibrate your transmitter with RC Assistant, and then calibrate X1 in Phantom 2 Assistant. If you accidentally installed the pot upside down, no need to tear everything down and start over, just switch from NORM to REV in the RC tab of the Phantom 2 Assistant.
    [​IMG]
     
  2. PJA

    PJA

    Joined:
    May 28, 2013
    Messages:
    368
    Likes Received:
    0
    Location:
    USA
    Hey Elguano...

    I did this slider mod with my original Phantom 1 TX without the LED awhile ago. I once showed you in another post. However, I also had a Slider Pot with a green LED and never knew exactly how to solder it on the TX Board to get it to work...

    The TX you are working with looks a little different inside than my original P1 TX... Are the LED solder points the same or in a different location of the original P1 TX board?
     
  3. ElGuano

    Joined:
    Sep 4, 2013
    Messages:
    2,219
    Likes Received:
    4
    Heya PJA! Yeah, I have the same mod (sans LED) on my P1 as well. The P2V+ TX is already version 5 of DJI's PCB, it's changed a LOT since the version 1.0/1.1 Phantom TX. So the solder points are almost guaranteed to be different. But the principles are the same:

    1. Find the datasheet for your pot. It should give you the pin-out. You will most likely have 5 pins. The ones labeled 1/2/3 are for the potentiometer, the remaining ones may be LED1/2 or E/B. These probably have polarity, but you can wire them up and tap the leads to your battery tray to see if it'll light up on 5v-6v. If it works, you now know the pins are the +/- for your LED.

    2. Now, all you need to do is find a ground and positive you can tap on your TX circuit board. It may easiest to do so at the power switch but there are probably free traces everywhere. The best way to verify is to break out the multimeter and confirm you're seeing voltage at a given connection (almost everything downstream of the switch is 3.3v, but it should still be enough to power the LED).

    3. Always test before you fly. Make sure you didn't tap into some open circuit that draws power even when the TX switch is off, and also make sure all your TX functions operate normally afterwards.

    I wish I had a green-LED version. Apparently all the ones I got were amber or red. The LED modules pull right out of the stalk though, so they're easy to replace.