After the build comes the setup. This post is mostly documentation for my own use.

Hardware & 3GX setup

Setting up the collective & cyclic pitch ranges is a bit more complex with a 3GX added to the mix. Obviously, you can switch the 3GX into bypass mode called “DIR” mode. This disables the 3 gyro-feedback loops and lets you control the servo’s directly. You can enter “DIR mode” by powering on the 3GX with its button depressed, and releasing the button as soon as the LED’s start cycling.

First thing to do was to set up my Tx into the correct CCPM mode: “SR-3”. To get the correct direction of movement, the aileron and elevator servo’s needed reversing. Since the three servo’s are identical, I did not need any specific end-point adjustments and left them all at 100/100. The neutral points were reasonably well set up mechanically, but still needed some fine-tuning with the “sub-trim” to get the swash absolutely level (Ail -22, Ele +6, Pit -12). I configured a collective pitch range of -12º to +12º by reducing the “Swash AFR – Pitch” to +30%. For cyclic pitch I set up ±9º (Ail -47%, Ele +47%).

After teaching the Tx the proper configuration, I also needed to configure the 3GX with the same info. This mostly boils down to setting the 3GX in the correct learning mode and moving a specific control on the Tx to copy the settings.

ESC setup

I kept the original settings for the archives. I configured the input voltage, pole count and gearing ratio into the software, which told me I should use the high speed governor mode. I left most of the other settings at the default. Here is the result in binary and readable form.

Tx setup

Finally I configured some features of my transmitter such as Fail/Safe and Expo. I’m too lazy to text-ify it all, so here’s the full config:

  • D/R,EXP
    • CH 1 (AILE), CH 2 (ELEV) & CH 4 (RUDD)
      • No UP & No DN
        • D/R: 100%
        • EXP: -15%
      • SW: A
  • END POINT
    • THR: 100/125
    • all the rest: 100/100
  • SUB-TRIM
    • AIL: -22
    • ELE: +6
    • PIT: -12
    • all the rest: 0
  • REVERSE
    • Reversed: AIL, ELE & THR
    • Normal: RUD, GYR, PIT, AU1, AU2
  • TRIM: all zero
  • THR-CUT: inhibit
  • SWASH-AFR
    • RATE-AIL: -47%
    • RATE-ELE: +47%
    • RATE-PIT: +30%
  • F/S
    • AIL: F/S +9%
    • ELE: F/S +3%
    • THR: F/S +17%
    • RUD: F/S 0%
    • GYR: F/S -25%
    • PIT: F/S -7%
    • AU1: NOR
    • AU2: NOR
  • AUX-CH
    • CH5: NULL
    • CH7: NULL
    • CH8: NULL
    • CH9: Sw-D, NORM
  • PARAMETER
    • TYPE: HELI(SR-3)
    • MODUL: PCM
    • ATL: ON
  • TIMER: 6 minutes, STk-THR 7%
  • Curves
    • THR-CURVE
      • NORM: 0% 55.5% 55.5% 55.5% 55.5% (2000rpm)
      • IDL1: 70% 70% 70% 70% 70%
      • IDR2: 80% 80% 80% 80% 80%
      • IDL3: 0% 25% 50% 75% 100%
    • PIT-CURVE
      • NORM: 40% 45% 50% 75% 100% (-2.5º -> +12º)
      • IDL1,2, HOLD: 0% 25% 50% 75% 100% (-12º -> +12º)
      • IDL3: 50% 50% 50% 50% 50% (0º)
    • REVO MIX: Inhibit
  • GYRO SENS
    • MODE: GY
    • UP: AVC 30%
    • DOWN: NOR 30%
    • SW: B
  • THR-HOLD
    • POSI: +17%

Leave a Reply

Anti-Spam Quiz: