Unable to Get VTX Control Working (Foxeer Reaper, “Tramp” Labeled, on UART TX4)

ArduCopter
1

I’m running ArduPilot on a TBS Lucid H7 flight controller and trying to get analog VTX control working with a Foxeer Reaper VTX that has “Tramp” printed on it. My goal is to control power level, band, and channel via Mission Planner or an RC switch.

Current Setup:

  • FC: TBS Lucid H7
  • VTX: Foxeer Reaper (analog, labeled “Tramp”)
  • VTX telemetry wire connected to TX4 on the FC
  • Video wire is connected to the “VTX” video pad on the H7
  • Power and GND are wired and confirmed functional
  • Live analog video feed is working correctly

ArduPilot Parameters Tried:

Attempt 1: IRC Tramp protocol

SERIAL4_PROTOCOL = 44
SERIAL4_BAUD     = 115200
VTX_ENABLE       = 1
  • Rebooted FC and Mission Planner
  • No VTX tab appears under Optional Hardware

Attempt 2: SmartAudio protocol (in case label is incorrect)

SERIAL4_PROTOCOL = 37
SERIAL4_BAUD     = 4800
SERIAL4_OPTIONS  = 4
VTX_ENABLE       = 1
  • Rebooted FC and Mission Planner again
  • Still no VTX tab, no response from VTX

What I’m Trying to Figure Out:

  • Is the Reaper VTX possibly mislabeled and actually using SmartAudio?
  • Does it require a specific startup timing or unlock sequence for control to be accepted?
  • Are there known compatibility quirks with Foxeer VTXs and ArduPilot?
  • Are any VTX_OPTIONS bits needed to enable comms?
  • Is there any success using this exact VTX with ArduPilot?

The quad is flying and the video feed works, so the core wiring and build are solid — I just can’t get serial VTX control to activate.

Any guidance or working configs would be greatly appreciated. I have used other non analog video systems so I know about how it should work but I cannot get the VTX options to pop up in the optional hardware screen. Thanks!