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Transmission Modes
WAVECOM Decoder W74PC, W-PCI/e, W-CODE, W-CLOUD Manual V9.1.0
SITOR-AUTO
Fully automatic tuning to signal center, shift and transmission modes SITOR-ARQ (Mode A) and SITOR-
FEC (Mode B) may be achieved by selecting
SITOR-AUTO
mode.
SITOR-FEC
The SITOR-FEC mode is used in broadcast applications where a return channel is not required or unavaila-
ble. Two sub-modes are in use: General broadcasting to a number of stations and selective addressing of
only one station.
Parameter
Value
Frequency range
HF
Operation modes
FSK, Broadcast/Simplex FEC
Modulation
FSK
Symbol rate
100.0 Bd
Receiver settings
DATA, CW, LSB or USB
Input format(s)
AF, IF
SITOR-FEC transmissions are used in maritime radio communication to distribute traffic lists, news, safety
and weather information. Amateurs also use the FEC mode for calls to all (CQ calls).
The selective FEC is used when the receiving station must operate under "radio silence" conditions and
hence cannot transmit.
In most cases SITOR-FEC transmissions uses a rate of 100 Baud using the standard shift of 170 Hz.
Each character is transmitted twice with an interval of 35 bits. In the case of error-free reception of both
characters, the character is displayed on the screen. The underscore (_) character is displayed if both
characters are received in error.
SP-14
SP-14 is an AM modulated sequential 14 tone mode, which is optimized for the transmission of numeric
codes.
Parameter
Value
Frequency range
HF
Operation modes
Broadcast/Simplex
Modulation
AM, SUB MFSK-14
Speed
133.3 ms
Receiver settings
AM
Input format(s)
AF, IF
Additional Info
14.891 MHz, 14.888 MHz, 15.791 MHz, 16.291 MHz.
The tone separation is 16 Hz. The center frequency is 409 Hz and the bandwidth is approximately 210 Hz.
Each tone has been assigned a character:
10 tones are assigned to the numerals 0...9
One tone is used as a start character
One tone is used as a stop character
One tone is used as a space character
One tone is used as a repetition indicator
