You can set the module to beep when RSSI drops below a threshold. More importantly, it supports a lost model alarm—if you power up your goggles near your downed quad, the module will trigger a beep on the VTX (if your VTX supports it via SmartAudio or Tramp).
The Furious FPV True-D is a 40-channel, true-diversity 5.8GHz receiver module. Unlike earlier modules that simply switched between two antennas, "true diversity" uses two independent receiver chips (RTC6715) and actively chooses the strongest signal in real-time.
Key Hardware Features:
But the firmware controls the brain.
Cause: You flashed True-D 2.0 firmware onto a True-D 1.0 board. Fix: You need to short the "Boot 0" pin to 3.3V on the STM32 chip (a small metal pin on the main processor). Use tweezers to hold the short while you re-flash the correct firmware.