User's Manual

18 82819_UM_ 40SMkII_E
1.2.2 DISTRESS LOCATION DETERMINATION
See figure 7.1.b
The location of the distress signal is determined by taking measurements of the doppler shift of the EPIRB frequency
when the satellite first approach and then pass the EPIRB.
The actual frequency is heard at the time of closest approach (TCA). Knowing the position of the satellite and using the
received doppler signal information, it is possible to determine the location of the Tron 40S MkII from the satellite at
the TCA. At the LUT, actually two positions are calculated. One is the actual position (A) and the other is the mirror
image (B) position. A second satellite pass confirms the correct location (A). With the 406 system the real solution can
be determined on the first pass with a reliability of nearly 90% and down to an accuracy of less than 5 km (3.1 miles).
1.2.3 EPIRB REGISTRATION
Normally the MCC will contact the vessel or the contact person registered in a shipping register and/or an EPIRB
register (Ships owner, family member etc.) before alerting the RCC. This is to determine if the alarm from the EPIRB
for some reason is a false alarm, and an expensive rescue operation can be avoided. Because of this it is important that
the ships data is correct in the shipping register or in the EPIRB database.
Tron 40S MkII purchased in some countries will have a registration form attached to it, it is important that this
registration form is completed by the owner and returned to the place the EPIRB was purchased or to the address
specified on the registration form.
Other countries use the already available shipping register to obtain the necessary information for a vessel in distress, in
these countries the ship is already registered and no registration form is necessary, however it is vital that the coding of
the Tron 40S MkII is kept up to date with data on the ship (nationality, call sign, etc.), to minimize the time from an
alarm to the start of the search and rescue operation. Reprogramming the Tron 40S MkII can be done at authorized
Jotron AS agents in more than 180 different places throughout the world.
If you are a resident of the United States, you must register this beacon with the National Oceanic and Atmospheric
Administration (NOAA) using the registration card included with the unit. Fill out the form and send it to:
SARSAT Beacon Registry, NOAA-SARSAT, E/SP3, FB4, Room 3320, 5200 Auth Road, Suitland, MD 20746-4304
Vessel owners shall advise NOAA in writing upon change of vessel or EPIRB ownership. Transfer of EPIRB to
another vessel, or any other change in registration information, NOAA will provide registrants with proof of
registration and change of registration postcards.