Adding Spektrum firing buttons

Discussion in 'Electrical & Radio' started by djranier, Feb 14, 2008.

  1. djranier

    djranier Well-Known Member

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    Hi All

    I just finished my first Spektrum Transmitter. It did take me 3 hours to do this, and I don't think I could shorten that much, maybe to 2.5 hours, just due to what needs to be done to the case, and fabrication of the button plate.

    Here are some pics of the internals, and the finished product. And it sure does make it easier to fire the guns. I never cared for the gymbol, joystick to fire.

    Here is the drawing to follow.

    633386051025644949.png

    Here is a internal view of my wiring.

    633386052287193371.png

    A closer view of the internal wiring.

    633386052546254213.png

    And the finished product.

    633386052787971416.png

    On the MWC site it has a explanation on how to add buttons To a Airtronics VG600 Transmitter by Brian Eliassen. Its his wiring drawing that I posted. He did a great job with it.

    Visit this site

    I wanted to leave the trim buttons installed just to make sure the holes were covered up, and you can see that I used the gymbal frame also to hold the button plate in place. If anybody would like me to, I can post a step by step explaination on how to do this. Only a few things are different from what Brian did, since the radio's are different internally.
     
  2. djranier

    djranier Well-Known Member

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    Since I cannot edit the above post, with the Spectrum, the wire color codes are not used. You determine what color you want.

    I used green, red, and black. With green on the left side, red to the center, and black to the right side. If you look closely at the internal pictures you can see that. I also tied together the switches, with 1 red, and 1 green jumper.
     
  3. JustinScott

    JustinScott Well-Known Member

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    Great job!
     
  4. JohnmCA72

    JohnmCA72 Member

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    That's how it works on any radio, as long as you have a proportional control channel. Substitute trimmers for any of the fixed resistors & you can tweak the end & middle points.

    Design consideration: What do you want to happen when you close BOTH switches at once?

    JM
     
  5. Reckless

    Reckless Active Member

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    simple question about this modification

    does the trim still work? I've never opened a radio to see if the trim is part of the gimble controls.. or seperately attached to the circuit.
     
  6. JohnmCA72

    JohnmCA72 Member

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    Some are, some aren't. On some radios, the trim physically moves the pot. relative to the stick. On others, it's in the input circuit itself. Still others have trim as separate inputs to the encoder.

    When I replace pots with switches, I use trimmers instead of fixed resistors so that I can put all of the important points where I need them easily. Once they're set, that's usually that & they don't need trimming "on the fly".

    JM
     
  7. Bob

    Bob Well-Known Member

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    The futaba & airtronics radios I have added buttons to the trim tabs are part of the gimbal assembly. I keep the stick and trim tabs in place by adding the buttons on the side of the case. I have found that i can fire faster with my finger then my thumb. I was never that good at Nintendo.
     
  8. rowboat captain

    rowboat captain Member

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    I just ordered the Futaba 6EX 6-Channel 2.4GHz I am looking for info on installing fire buttons. Can I install the buttons and keep the gimbal assembly so i could use either or?

    thanks
     
  9. Bob

    Bob Well-Known Member

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    Yes you can. That's how I do mine. Just drill mount the buttons on the side of the radio.
     
  10. Tugboat

    Tugboat Facilitator RCWC Staff Admiral (Supporter)

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    I added buttons to my Spektrum, and left the trim buttons connected so I can use the software trim. Works fine.

    Your work looks beautiful! Very similar to mine, so I could be biased :)
     
  11. Powder Monkey

    Powder Monkey Active Member

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    Man I wish I had the sack to cut into mine but I don’t so I will continue to use the stick.[V]
    Tug you should start a Radio reconfiguring company. MOTO "we will make it easier for her to push your buttons" [;)]
     
  12. rowboat captain

    rowboat captain Member

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    Just got do setting my spektrum up with firing buttons. I found that I had to remove the 2.2k resistors from the red and black wires. with the resistors in place the servos would bearly move. it was real easy. the hard part was making up the bracket to hold the firing buttons.
     
  13. Tugboat

    Tugboat Facilitator RCWC Staff Admiral (Supporter)

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    I used 1.1k and 3.7k resistors (I think, they're out in the shop, not here by the coffee)
     
  14. djranier

    djranier Well-Known Member

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    Yes I heard that 1k, and 3.3k gives better stick resolution on the Spektrums.
     
  15. jackpkt

    jackpkt Member

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    I was interested in doing this, with my Spectrum DX6i.

    Is there more detailed instructions other then these and the old Brian Eliassen article?
    I am not sure where these 1k and 3.3 resistors go, and seems like some resistors were being removed. I am also very keen on this idea because I think with the buttons i can also add digital counters to keep track of the ammo in each gun. i.e. just count up as the button is fired, and have a rest switch for all displayed when you end the battle.
     
  16. SteveT44

    SteveT44 Well-Known Member

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    Buttons are fairly simple. For each set of two buttons, it's just the four resistors soldered in a row with the buttons wired across the two center resisters. The four resistors replace the variable resistors (potentiometers) in the joystick.

    Here's a pic of my setup (ignore the switch on the bottom, it's a more complex three speed setup for my pump). For the push button resistors, you feed 5v into one side (red wire) and the other end is grounded (black wire). What used to go to the center wiper on the joystick potentiometer (green wire) taps between the two center resistors as shown.

    upload_2017-2-6_17-39-9.png


    Your wire colors might not match what is show but they're easy to determine by looking at the joystick and testing with a multimeter. Most joystick will have three wires going to each axis potentiometer (5v, center tap, ground). Some setups may have a little circuit board connecting the two potentiometers with the wires soldered to that.


    upload_2017-2-6_17-45-25.png

    upload_2017-2-6_17-45-59.png
     
    Last edited: Feb 6, 2017
    jackpkt likes this.
  17. Captain obvious

    Captain obvious Active Member

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    Very nice. I plan on doing this to my radio when I get the build done.
     
  18. jackpkt

    jackpkt Member

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    Thanks so much very helpful.
     
  19. jackpkt

    jackpkt Member

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    anybody have any ideas on adding an ammo display for each of the firing buttons?
    I was thinking a simple counter could work nicely but wondering if anyone has done that before. I found these very small golf stroke counter with a small display that I could just pull the board out and cut the display above each button, remove the button that does the count and wire the leads to the firing button. Thoughts?
     
  20. SnipeHunter

    SnipeHunter Well-Known Member

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    I've built a number of shot counters over the years. I have them on all my radios and have installed them for a few other people too. There is a picture of my current radio in my Bismarck thread (in stem to stern warships in detail) if you want to see what mine looks like installed. Not sure if there are any pictures of the guts online.

    I think they are extremely useful and have improved how I battle.

    How hard they are too make depends on how good with electronics you are. If you can just hack up some existing counters and get them to work more power to you. Microcontrollers and small displays are cheap, easy to use, and readily available so going with a more custom electronics package is doable if that's your thing. My current design is integrated with the radio, so I don't have to remember to turn it on or worry about the battery going dead.