anchor.diff:      let Voyager = "VG"
   
   type SonarBeacon = {
  -    timestamp: DateTime
  -    srcIpAddr: IPAddress
  -    serialNumber: SerialNumber
  -    systemType: SystemType
  -    softwareVersion: SoftwareVersion
  -    connectionState: AvailabilityState
  -    cpuTemp: float32 option
  -    isDiverHeld: bool
  -    isVoyager: bool
  +    Timestamp: DateTime
  +    SrcIpAddr: IPAddress
  +    SerialNumber: SerialNumber
  +    SystemType: SystemType
  +    SoftwareVersion: SoftwareVersion
  +    ConnectionState: AvailabilityState
  +    CpuTemp: float32 option
  +    IsDiverHeld: bool
  +    IsVoyager: bool
   }
   
   // Defender beacon
  
positive.code:     | OnTetherPower = 4
  
  type DefenderBeacon = {
      timestamp: DateTime
      srcIpAddr: IPAddress
      serialNumber: SerialNumber
      systemType: SystemType
      softwareVersion: SoftwareVersion
      connectionState: AvailabilityState
      recordState : OnBoardRecordState option
      storageState : OnBoardStorageState option
      storageLevel : float32 option
      batteryState : OnBoardBatteryState option
      batteryLevel : float32 option
  }
  
  // Command Module Beacon
  
negative.code: type StatusHolder = { mutable status: AvailableSonarStatus }
  
  module BeaconListeners =
      type SonarAvailability  = Aris.Availability
      type DefenderAvailability = Defender.Availability
      type CMBeacon = Aris.CommandModuleBeacon
  
      open Beacons
  
  