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Vesper Marine AIS Watchmate 850 Transponder
Get back up to $50 with purchase of any Vesper Marine Transponder via manufacturer mail-in rebate. This item is eligible for a $30 rebate. See rebate form for details. Ends 5/25/19.

Vesper Marine AIS Watchmate 850 Transponder

  • Display with Built in Class B AIS Transponder
  • Emits Audible Warning Alarms
  • Includes a Built-in GPS Receiver and Internal Patch Antenna
  • Item #: 
    Vesper Marine
    Model #: 


    Shipping Weight: 
    3.00 Lbs.
    Our Price:
    Status:    null In Stock

    Quantity : 

    Important Information Regarding the Purchase of a Class B AIS:
    When you are ready to place your order, you will need to complete the AIS Static Data Programming Log.

    This required form must be sent to Defender Industries via e-mail or faxed along with a copy of your MMSI registration before your order can be processed. Our fax number is 860-701-3432.

    Because each transponder can only be programmed once with your personal MMSI number, orders CAN NOT BE CANCELLED AND ARE NOT RETURNABLE after orders have been placed.

    Avoid confusion with other functions with a dedicated AIS control system!


    • Integrated AIS Transponder -Includes a built-in AIS Transponder with two channel parallel receiver and transmitter. This high performance transponder means greater range and increased safety. It also makes installation easier. No external "black boxes" to mount, power and wire. Just plug in a VHF antenna and connect theAISWatchMate850 Transponderto your 12 or 24 volt power supply.
    • Class A, Class B and AIS SART & MOB- The perfect companion for AIS Search and Rescue and Man Over Board devices, including the latest models. Sounds the alarm whenever an AIS-SART or AIS-MOB is triggered. Clearly identifies them on the display and provides continuous position updates as well as bearing and range to the SART or MOB.
    • Galvanically isolated (GI) ports - Protects your transponoder and marine equipment from high current damage
    • Ultra-Low power consumption-Designed for minimal power consumption theAISWatchMate850 Transponderis extremely well suited for energy conscious vessels.
    • Integrated GPS Antenna - Includes a built-in GPS patch antenna that provides GPS data to the integrated 50 channel GPS receiver. This internal patch antenna allows for simple installation. However if needed, an external GPS antenna connection is provided and an optional external antenna is available. For best performance, the built-in GPS antenna requires a clear and unobstructed view of the sky.
    • Fully Waterproof Including USB Connection- The water proof USB connection can be used to connect to theAISWatchMate850 Transponderduring configuration and makes for an easy connection to onboard or home computers if required.
    • Anchor Watch - The anchor watch enables you to mark where you dropped anchor and sounds an alarm if your vessel moves outside an adjustable circle. It provides a helpful visual indication of where within your anchor circle the boat is located along with distance and bearing to the anchor point.
    • Direct Selective Calling (DSC)-Using the DSC function from your WatchMate allows you to initiate an “individual station call” to vessels that are displayed on your WatchMate screen. This feature makes it easy to message nearby boats, requesting them to switch to a specific channel for a VHF call.
    • Target Plot-Provides a radar-like display of all vessels within the selected range. The display can be oriented north-up or heading-up so it's very easy and natural to interpret. Dangerous and lost targets are readily identified.
    • Graphical Plot Shows Crossing Situations - Shows the relative position of a target vs. your vessel at the closest point of approach. This provides a graphical view of the crossing situation and clearly indicates whether a target will pass ahead or behind.
    • CPA and TCPA-Computes the closest point of approach and time until CPA. Alarms may be based on these and other factors.
    • Bearing and RangeComputes the bearing and range to each vessel. Bearing can be displayed in magnetic to facilitate easy visual identification using your compass and binoculars. Bearings can alternatively be displayed in true or relative to your vessel's heading.
    • Prioritization-Vessels and alarms are presented in priority order.
    • Intelligent Filtering-In crowded operating areas theAISWatchMate850 Transpondereliminates clutter and false alarms with sophisticated filtering options.
    • Identify your "fleet"-Targets marked as members of your fleet are displayed with a special icon. Use this to indicate your friends or vessels you commonly work with.
    • CPA alarm-Triggers alarm if a vessel will come too close. Full control of alarm parameters.
    • Guard alarm-Sounds alarm if any vessel comes within the specified range. Both CPA alarms and guard alarms may be used together.
    • External alarm trigger-In addition to the internal alarm, an external buzzer, alarm, or signal light can be interfaced without requiring any additional relays (max 150mA).
    • Consise and easy to read displays-Uncluttered easy to read display shows all available AIS data.
    • Safety messages-Displays received AIS Broadcast Safety Messages. These messages may contain important safety, navigation, weather, or shipping information. An AIS mayday safety message can also be sent directly from theAISWatchMate850 Transponder.
    • Aids to navigation-Full support for AIS aids to navigation including off-position and virtual aid indicators.
    • Meteorological and hydrographic display-Displays real-time wind, current, tidal and much more in areas where this information is broadcast.
    • GPS receiver-Displays built-in GPS satellite status and navigation data such as your position, heading, course and speed.
    • Large backlit LCD-Adjustable daylight viewable backlit 125mm (5") LCD.
    • Easy to use-Four buttons control all features. Each button is clearly labeled on-screen. Buttons are backlit for night time use and illumination brightness is controllable. Each setting has on-screen help.
    • External interface-TheAISWatchMate850 Transponderprovides complete AIS and GPS output and is easily interfaced to chart plotters, radars or computers.
    • Silent Mode-AllowsAISWatchMate850 Transponderto be put in Silent Mode. When in this mode, the AIS receivers and GPS continue to operate normally and all alarms and other features, including the Anchor Watch, are available. The only change is all transmissions are inhibited (except MayDay). Perfect for those times when you want privacy.
    • VHF "in use" indicator-Unique VHF “in use” indicator (When used with Vesper Marine’sVHF splitter).
    • Self Diagnosis-Self diagnosis to provide warnings if AIS, GPS or antenna are not functioning.


    Size* 208 mm wide x 135 mm high x 76 mm depth ( 8-3/16" x 5 5/16" x 3" )
    LCD panel 125 mm (5") grayscale sunlight viewable 320x240
    LCD light level Off and multiple levels of brightness
    Environmental Waterproof (IP67: submersible to 1m for 30 mins)
    Operating temperature -25°C to +55°C (-13°F to 131°F)
    Power supply 12-24 Volt DC 3 Watts nominal
    Number of receivers (2) AIS, (1) DSC (Timeshared)
    Receive Sensitivity -113 dBm (<20% PER)
    Number of transmitters (1) AIS
    TX Power output 33 dBm (2 Watt)
    GPS Built-in 50 channel GPS receiver with SBAS (satellite based augmentation systems such as WAAS & EGNOS), selectable smoothing, internal antenna, TNC for optional external antenna
    GPS sensitivity -159dBm tracking & navigation
    -142dBm acquisition (cold start)
    GPS accuracy Position 2.5m CEP, SBAS 2.0m CEP
    External alarm maximum 150 mA (power supply voltage)
    VHF antenna required PL-259 connector. 50 ohm, max 2:1 VSWR
    Serial data (1) USB port (mini), (1) NMEA 183 input (RS422 4800/38400 baud), (1) NMEA 183 output (RS422 4800/38400 baud)
    AIS Messages Displays all class A and class B position reports, voyage data, static data, aids to navigation, SAR aircraft, SART, MOB, meteorological/hydrographic and safety messages
    Protocols IEC 62287, IEC 60945, IEC 61108, IEC 61162, ITU-R M.1371, ITU-R M.825, ITU-R M.1084
    Approvals BSH, BABT, CE, US Coast Guard, US FCC, Transport Canada, IC
    * Size does not include bracket or cable
    (Specifications may change due to product improvements. )

    Kit Includes:

    • (1) WMX 850
    • Protective cover
    • Mounting brackets with thumbscrews
    • Flush mounting hardware
    • 6.5 ft (2 mr) Power / Data cable
    • 3 ft (1m) USB Cable
    • Flush mounting seal and screws

    What is AIS:
    The Automatic Identification System ( AIS ) improves the safety level of boating by exchanging information about the status of your ship with other AIS-equipped craft nearby. AIS targets are constantly visible even when they are shrouded in fog, in darkness, behind headlands, river bends or other obstructions.

    • Class A AIS is designed for Commercial and SOLAS Vessels
    • Class B AIS is designed for use on non-SOLAS craft

    Note: Vesper continually provides free updates for any upgrades or improvements made to their product, so you can be assured of the latest and greatest features.

    Documentation available at the following links:

    Shakespeare 5215-AIS Masthead Squat Body Antenna
    Item #: 257469
  • 3 Foot Stainless Steel Whip
  • VHF Marine Band 3dB
  •  Include
    Reg. Price

    Sale Price

    Model #:
    Vesper Marine External GPS Antenna
    Item #: 258468
  • Applications: AIS WatchMate WMX850 Class B AIS Transponder Only
  • Fully Weatherproof, Ultra-high Sensitivity
  • Multiple Mounting Configurations
  •  Include

    Model #:
    Vesper Marine USB Cable
    Item #: 258469
  • Designed for WatchMate 850, XB-9000, XB-8000 Transponders
  • Includes (1) Fully Waterproof USB connector and (1) Standard USB Connector
  • Length: 16 Feet
  •  Include

    Model #:
    Vesper Marine VHF / AIS Antenna Splitter
    Item #: 258471
  • Applications: All AIS Transponders and Receivers
  • Function: Enables AIS to Share a Single Antenna with VHF and AM/FM Radio
  • Power: 12 - 24 Volts DC, Includes Built-in Low Noise Amplifier
  •  Include

    Model #:
    Digital Yacht AISLG Life Guard Man Overboard Alarm System
    Item #: 259790
  • Connect and Listen to AIS Data via NMEA 0183 Input, Listen to all AIS Traffic
  • Internal 95 dB Buzzer Alarms when AIS SART Message 1 and 14 are Detected
  • Includes Audible and Visual Alarms, Easy to Install IP54 Black Box Solution
  •  Include
    Reg. Price

    Sale Price

    Model #:
    Shakespeare Coaxial Cable Connector
    Item #: 254173
  • Type: Solder-on
  • Orientation: Male, Sold Individually
  • Function: Connects RG-8AU or RG-213 Coax Cable, Material: Gold-Plated Brass
  •  Include
    Reg. Price

    Sale Price

    Model #:

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