SI-TEX MDA-4 VHF-FM DSC Radio w/Built-In AIS

SI-TEX MDA-4 VHF-FM DSC Radio w/Built-In AIS
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VHF-FM DSC Radio w/Built-In AIS

The SI-TEX MDA-4 is type approved and ready for action on recreational and commercial fishing boats,  workboats and more. This rugged package combines an advanced VHF-FM/DSC radiotelephone with a quality built-in Dual Channel AIS Receiver.

All the features professionals expect — at an unexpectedly low price:

  • Ruggedized to Military Specifi cation (MIL-STD-801G*), to stand up to tough conditions and years of hard professional use
  •  Dual Watch, Tri-Watch and Programmable Scanning Modes
  • Robust 25W loud hailer/foghorn with eight selectable modes and listen back
  • Optional full-function Remote Command microphone and GNSS 66-channel smart GPS antenna
  • High-performance dual-channel AIS receiver
  • Standard 2-year warranty

The large LCD display provides important AIS data like MMSI, Call Sign, Ship’s Name, Bearing, Distance,  Speed Over Ground and Course Over Ground, along with alerts for Closest Point of Approach and Time to Closest Point of Approach. The MDA-4 can also provide important navigation data like Lat/Lon, Date, Speed
Over Ground and Course Over Ground. The MDA-4 delivers a boatload of advanced features for an affordable price



  • Dimensions (LWH): 8" x 4.25" x 2.25"
  • Dims w/Bracket (LWH): 8.5" x 5.25" x 2.25"
  • Weight: 3.3lbs
  • Connectivity: NMEA2000, NMEA0183
  • Power Supply: 13.8V DC
  • Environmental: MIL-STD-810G*, ITU Standards, IPX7 Waterproof


  • Frequency: 161.975MHz/162.025MHz
  • No. of Channels: (2) Dual Channels
  • Local Oscillator Mode: PLL
  • Ambient Operating Temperature: -15° C to +55° C


  • TX Frequency: 156.025-157.425 MHz
  • RX Frequency: 156.050-162.025 MHz
  • Channels: All USA, Canada and INT channels, plus private channels
  • Microphone: Wired handheld channel up/down, power high/low and quick 16/9 channel access, extra-long mic cord for commercial wheelhouses
  • Modulation Mode: FM (16K0G3E/DSC (16K0G2B)
  • Antenna Impedance: 50 Ω nominal
  • Receiver Sensitivity: 0.22 micro-volts (SINAD-12 dB)
  • Spurious Response Rejection: 70 dB
  • Adjacent Channel Rejection: 70 dB
  • Audio Output Power: 5W @ 4 Ohm
  • Hailer/Fog Horn Audio Output Power: 25W @ 8 Ohm
  • Audio Distortion: 5%
  • RF Output Power: High 25W/Low 1W
  • Harmonic Emissions: 0.25 µ W

* Meets MIL-STD-810G specifi cations for Altitude, High Temperature,Low Temperature, Temperature Shock, Contamination by Fluids,Solar Radiation, Rain, Humidity, Salt Fog, Sand & Dust, Immersion,
Vibration, Shock)

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