transmitter.cs

[RequireComponent(typeof(PlayerInput))]
public class Transmitter : MonoBehaviour {
  private Receiver receiver;
  private PlayerInput playerInput;

  void Start() {
    this.playerInput = this.GetComponent<PlayerInput>();
    this.playerInput.enabled = true;
    Registry.Instance.GetNewReceiver(this);
  }

  public void Connect(Receiver receiver) {
    // Somewhat clumsily, be sure that evey other possible camera is disabled
    // we activate the new one.
    foreach(Camera c in Camera.allCameras) c.gameObject.SetActive(false);
    this.receiver = receiver;
    this.receiver.receiverCamera.gameObject.SetActive(true);
  }
  
  // ...
}