ESP32-H2 GPIO10 (UART1 TX)
                          |
                          v
                    +-----+-----+
                    |    1kΩ    | Pull-up
                    +-----+-----+
                          |
                          +--------+
                          |        |
                    +-----+-----+  |
                    |  NPN BJT  |  |  BC817 or 2N3904
                    |   Q1      |<-+
                    +-----+-----+
                          |C
                          |
              +-----------+
              |           |
         +----+----+  +---+---+
         |   10Ω   |  | 100pF | Snubber
         +----+----+  +---+---+
              |           |
              +-----------+--------> To Track (via DCC cutout)
                          |
                          |
                    +-----+-----+
                    |   10kΩ    | Pull-down
                    +-----+-----+
                          |
                          v
                         GND

   RailCom Cutout Detection (Optional GPIO11)
   
        Track Signal ---+
                        |
                    +---+---+
                    |Voltage|  Resistor divider
                    |Divider|  22kΩ / 10kΩ
                    +---+---+
                        |
                        +---> GPIO11 (Cutout Detect)
                        |
                    +---+---+
                    | 0.1µF | Filter capacitor
                    +---+---+
                        |
                       GND