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Stubb edited this page May 5, 2026 · 5 revisions

Running Lights (Navigation Lights)

Mount Specifications

Both bow and stern running light mounts are identical:

  • Plate shape: Rounded rectangle
  • Plate dimensions: 4½" × 3½" (width × height)
  • Mounting holes: 2 holes, 2½" on center spacing

Measurements taken April 2026 for replacement fabrication.

Status

Current mounts need replacement. See issue #73 for tracking.

AIS

MAIANA open-source AIS transponder integrated with OpenPlotter.

  • MMSI: 338554042
  • Class B transponder
  • Antenna in transom tube, sealed with silicone (2026-04)

Autopilot

  • Raymarine p70R display + X-10 course computer (Evolution / SeaTalk NG / NMEA 2000)
  • Autopilot remote: pending (open issue)

Compass

  • Ritchie SP5 binnacle compass

OpenPlotter setup

  • Hardware: Raspberry Pi 5, MacArthur HAT
  • Storage: 128 GB Raspberry Pi USB Flash Drive (power-loss resilient — replaces SD card after corruption)

MAIANA AIS (NMEA 0183 over UART)

  • Connection: UART0 → ttyAMA0 (NOT ttyAMA10 — that's the Pi 5 debug UART)
  • Baud: 38400
  • Cable: RJ45 to MAIANA antenna unit, ~25 ft Cat6, T568B
    • Pin 1 (Orange/White) = 12V
    • Pin 2 = TX
    • Pin 3 = RX
    • Pin 4 = GND
    • Pin 8 = GND
  • Power: HAT supplies 12V to MAIANA via RJ45
  • Signal K: Serial app → enable UART0 → reboot → ttyAMA0 alias maiana, NMEA 0183, 38400 baud → Connections tab → Add to Signal K → AUTO

Signal K → Home Assistant bridge

The OpenPlotter Pi publishes raw Signal K deltas to the HAOS Pi's Mosquitto broker so the operational-state layer (mode auto-detection, position helpers, etc.) can consume them.

  • Plugin: signalk-mqtt-home-assistant (configured via SK admin → plugins). Min publish interval: 60 s.
  • Topics published (bare, NOT under homeassistant/):
    • navigation.position — {\"value\": {\"latitude\": ..., \"longitude\": ...}, ...}
    • navigation.speedOverGround — {\"value\": <m/s>, ...}
    • navigation.courseOverGroundTrue — {\"value\": <radians>, ...}
  • Auth: SK plugin authenticates to Mosquitto via a dedicated HA user (Mosquitto add-on default = HA users).
  • HA discovery: not provided by the plugin despite the name. Discovery configs are published from the refit repo (scripts/ha_setup/signalk_mqtt_discovery.py) — these create sensor.defiant_signal_k_* and device_tracker.defiant_signal_k_defiant. See Vessel-Management-System for the full integration picture.

NMEA 2000 (CAN bus via MacArthur HAT)

  • Driver: MCP251xfd (NOT MCP2515)
  • Interface: SPI0 CE1
  • Oscillator: 20 MHz (20000000)
  • Interrupt: GPIO 25
  • Backbone wiring: CAN H, CAN L, GND only (skip 12V if backbone is separately powered); 3A fuse on backbone power
  • Verify: ip link show can0 should show UP

MFD / Plotter

  • B&G Vulcan 7 chartplotter / MFD (2019)
  • 2 × B&G Triton instrument displays (2019)
  • B&G wind transducer with NMEA 2000 cable (installed during 2019 mast unstep)
  • B&G screens / radar wiring pending (open issue)
  • B&G dedicated fuse block pending (open issue)

Helm tablet

Daylight-readable Android tablet at the helm, mirroring OpenPlotter over the local network. ~1300 nits sustained, IP68. Specific tablet model and remote-viewer details redacted.

Radar

  • Furuno 1715, 36 nm range

Depth

  • Depthfinder working (Airmar through-hull transducer, replaced since original listing)
  • Specific model ❓

VHF

  • Uniden 525 fixed-mount at the nav station
  • West Marine handheld VHF (backup — see Safety)

Power requirements

Device Continuous draw Fuse Wire
Furuno 1715 ~3A (~35W) 10A 14 AWG
B&G Vulcan 7 ~3A 10A 14 AWG
B&G Triton (×2) ~1.5–2A each 5–7A 16 AWG

Total ~10–11A continuous. Previous owner had 30A fuses on 12/2 — fire hazard. Replace per spec.

Charts

  • NOAA ENC vector charts via OpenCPN Chart Downloader plugin
  • Priority regions: US4MD (Chesapeake MD), US4VA (Chesapeake VA), then US4DE / US4NJ / US4NY for northbound

Networking / nav-desk Pis

  • 3 × Cat6 runs from cabin to transom (Starlink, AIS, spare)
  • Network switch installed at nav desk
  • Pis at nav desk: NAS, manager, Jellyfin clients (see Entertainment for media stack details)
  • 5V rail at nav desk for Pis
  • Anchor alarm running on Pi cluster
  • OpenPlotter Pi 5 mirrors to the helm tablet over the local network

Internet stack

Summary — full detail on Connectivity:

  • Starlink Gen 3 Standard (flat dish, Starlink Plug connector, no SPX adapter)
  • 12V→56V PoE injector for the dish (specific model redacted)
  • Cellular-capable router (specific model redacted — see Connectivity)
  • Victron Orion-Tr 12/12-18 isolated DC-DC upstream of both — replaced an unstable DROK converter

Open Items

  • Wire B&G screens + radar
  • Connect MPPTs to Cerbo via VE.Direct (see Electrical — confirmed dead end on cabling, pursuing BLE Instant Readout)
  • Autopilot remote
  • B&G fuse block
  • Replace running light mounts (see above)

Parts list

To populate.

Defiant

Systems

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