✅ What is the EPIRB Identification Code?

Every EPIRB (Emergency Position Indicating Radio Beacon) has a unique 15-character hexadecimal code permanently programmed into it.
This code is:

  • Registered to your vessel
  • Transmitted during a distress activation
  • Used by the NOAA SARSAT system to identify:
    • The vessel name
    • Your contact information
    • Vessel description
    • Emergency contacts
    • MMSI (if applicable)

This is the number the Coast Guard uses to know WHO is calling for help.


📍 Where do you find the EPIRB ID?

You’ll find the code:

  • Printed on the EPIRB label (often called “HEX ID,” “UIN,” or “15-Hex Code”)
  • In the EPIRB’s manual or included paperwork
  • On your NOAA EPIRB registration confirmation email

It looks like this:

ABC123456789FFF
(15 characters, letters and numbers)


🔥 What does it do?

When your EPIRB activates, it sends:

  • The UIN/HEX ID
  • Your GPS coordinates (if it’s a GPS-enabled EPIRB)
  • A 406 MHz distress burst to the satellite system

The satellite relays this to the rescue coordination center, who pulls up your registration info tied to that EPIRB identification code.

✅ 1. What an EPIRB Does (and DOES NOT Do)

✔ EPIRB DOES:

  • Sends a 406 MHz distress signal to satellites
  • Includes your EPIRB Unique ID (HEX ID) — not your MMSI
  • Sends your GPS coordinates (if GPS-equipped)
  • Alerts NOAA + U.S. Coast Guard directly
  • Works anywhere in the world, even without your radio or Simrad

✘ EPIRB does NOT:

  • Use VHF channels
  • Integrate directly into your VHF radio
  • Show up on AIS
  • Send your MMSI
  • Display on your Simrad as a vessel

➡ EPIRB ≠ MMSI
➡ EPIRB distress = satellite system
➡ MMSI distress = VHF/DSC system


✅ 2. What MMSI Does

Your MMSI (Maritime Mobile Service Identity) is:

  • A 9-digit number programmed into your DSC VHF radio
  • Used for Digital Selective Calling (DSC) emergencies over VHF
  • Used for position polling, DSC distress button, and boat-to-boat calling

✔ MMSI is used for:

  • The red DISTRESS button on your VHF
  • Sending your position through your VHF to nearby boats
  • DSC calls to other MMSI-equipped radios
  • AIS transponders (if you get one)

✘ MMSI is not used by EPIRBs

EPIRBs have their own ID.


✅ 3. What DSC (Digital Selective Calling) Does

DSC is part of your VHF radio. It uses:

  • Channel 70 (digital VHF)
  • Your MMSI
  • Your GPS position (from your radio or Simrad NMEA2000 network)

In an emergency:

Pressing the DISTRESS button on your radio sends:

  • Your MMSI
  • Your GPS coordinates
  • A distress alert to:
    • U.S. Coast Guard
    • All boats within VHF range

➡ DSC is short-range (20–40 miles depending on height)


✅ 4. What AIS Does

AIS is Automatic Identification System.

AIS-equipped vessels send:

  • Vessel name
  • MMSI
  • Speed / heading
  • GPS position
  • Vessel type / size

Your Simrad GO unit:

Your Simrad can receive and display AIS targets, if you attach an AIS receiver or a VHF radio with AIS built in.

EPIRBs DO NOT use AIS

Except special EPIRBs:

  • AIS-EPIRBs (newer type) transmit BOTH 406 MHz + AIS Man Overboard style signal
  • These do show up on your Simrad, but they are specifically marked EPIRB or SART targets.

✅ 5. How all of this connects to your Simrad GO9

✔ EPIRB

  • Does not integrate into Simrad
  • Does not use your VHF or MMSI
  • Works totally independently
  • Distress is handled by satellites + USCG

✔ DSC VHF Radio

Your Simrad GO9 can feed GPS position to your VHF radio over NMEA2000.
This means:

Simrad → GPS → VHF → DSC distress call

So your DSC distress will include accurate coordinates.

✔ AIS Receiver / AIS VHF

If your VHF radio has AIS built in (like SIMRAD RS40-B):

  • AIS targets will appear on your Simrad chart
  • You’ll see boat names, MMSI, and CPA/TCPA
  • You can tap an AIS target on the Simrad and directly call it via DSC

➡ AIS + DSC work together
➡ EPIRB is completely separate


🎯 6. How These Systems Complement Each Other

SystemTriggerWho Receives ItNetwork UsedYour Simrad Shows It?
EPIRBAuto/manualSatellites, NOAA, USCG406 MHz❌ No (unless AIS-EPIRB)
DSC Distress (VHF)Manual DISTRESS buttonUSCG + nearby boatsVHF Ch 70❌ No (Simrad does not show DSC)
AISAlways transmittingAll AIS-equipped boatsVHF AIS channels✔ YES (Simrad shows AIS targets)
MMSIID in VHF/AISUsed in DSC/AISDSC + AIS✔ AIS MMSIs displayed

🧭 7. So Is EPIRB the Same as MMSI?

NO — they are totally different:

EPIRB:

  • Has a HEX ID
  • Uses satellites
  • Worldwide range
  • Does NOT need your radio or Simrad

MMSI:

  • Used for DSC and AIS
  • Short to medium range
  • Completely different system

🚤 What YOU Would Use on Your Robalo R202EX

Best Setup:

  • DSC VHF with GPS/Simrad tie-in
  • AIS receiver or AIS-enabled VHF (RS40-B)
  • Standard GPS EPIRB (or AIS-EPIRB if you want it to show on your Simrad)

This gives you ALL layers of safety:

  1. VHF voice
  2. DSC distress
  3. AIS visibility
  4. EPIRB satellite rescue

Perfect for ICW, ocean trips, or future offshore runs.