Author's explanation
Priority 0 (zero) is routine priority. (On some makes of eqUIpment, this priority is
automatic and does not have to be keyed for individual calls).
For routine telephone calls -the LES will normally use 'companders' to improve
voice quality. To access a telephone channel with 'companders-in' -key 7 (hence 07
above - 0 giving you routine priority; 7 giving you 'companders-in ').
73 is the LES ID for Thermopylae, Greece (the desired LES).
Pressing the * key, in this example, 'initiates the call' (your keyed numbers are not
sent to the NCS until you press the * key. Check your own manufacturers instructions
to make sure your equipment does not use a different key for call initiation).
The NCS will connect you with your chosen LES, on a working channel. When
connected, the LES sends a 'dial tone' This should happen within 75 seconds.
On receipt of the dial tone - enter 00 (international call, even if the call is to the
country where the LES is situated); the country code; the subscriber telephone
number, starting with the area code but (normally) without the leading zero. End
the number with the * key (the 'OOcountry-codeNumber' is not passed to the LES
until you press the * key, or whichever key is used on your own equipment).
Your call will be connected automatically and, normally, charged by the amount of
time spent on the voice channel.
Code '00' is always used to indicate a normal, routine,
international telephone, fax or voice-band data call. Other '2-digit
codes' shown in ALRS Vo!. 1, which would be used in place of
'OOccNumber' include:
- 12# - to connect you with 'International Information' in the country
where the LES is located (to find the telephone number for a
subscriber in another country).
- 14# - to connect you with 'National Information' in the country
where the LES is located (to help find a telephone number for a
subscriber in that country).
- 68# - to connect you with the Customer Service Desk for the LES
called (to let you complain, or ask for the latest call charges etc)
e.g., On receipt of dial tone from Thermopylae - key 68# to
connect with the customer service desk for that LES.
(Codes for Distress, Urgency and Safety services are shown in Chapter 5)
Inmarsat-B PC Telephone Calls
Inmarsat-B, introduced in 1993 as the 'digital successor' to
Inmarsat-A, uses a single-stage (not two-stage) connection process for
telephone, fax and data calls. Inmarsat-B equipment is programmed with
a 'preferred/default LES' for each Ocean Region. When you want to
make a telephone call, therefore, you only have to:
MARINE COMMUNICATIONS 63
