Clover-2500, Codan-selcal, Codan-9001 – Wavecom W74PC V8.7.0 User Manual
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Transmission Modes
WAVECOM Decoder W74PC, W-PCI/e, W-CODE, W-CLOUD Manual V8.7.0
CLOVER-2500
CLOVER-2500 is almost identical to CLOVER-2000. The only differencies are as follows:
Baudrate: 78.125 Bd (CLOVER-2000: 62.5 Bd)
Spacing: 312.5 Hz (CLOVER-2000: 250 Hz)
Center: 1562.5 Hz (CLOVER-2000: 1500 Hz)
Otherwise the mode has the same features as CLOVER-2000.
CODAN-SELCAL
The mode was developed by the Australian CODAN PTY. and is very similar to GMDSS/DSC.
Parameter
Value
Frequency range
HF
Operation modes
Digital Selcal
Modulation
FSK
Symbol rate
100.0 Bd
Receiver settings
DATA, CW, LSB or USB
Input format(s)
AF, IF
Additional Info
ITU R M.493 alphabet
CODAN SELCAL operates with 100.0 Bd and can be started by selecting the mode.
A preamble of at least 100 dot reversals, which are 50 changes between "0" and "1" (low and high bit),
precedes the data block. This lead-in has duration of 2.0 seconds. Digital MARK "1" is represented by a
frequency of 1870 Hz and SPACE by 1700 Hz.
The dot pattern is followed by a word synchronization sequence called the "phasing preamble". The char-
acters no. 125 and no. 108 are alternately transmitted for 1.2 seconds.
This sequence is followed by the data block with different control characters and the message. Each data
byte consists of 7 data bits and 3 parity bits. Thus the duration of each character is 100 ms.
Selecting Options | Display offers the option of an ASCII or RAW bits display.
CODAN-9001
CODAN-9001 is an asynchronous adaptive ARQ system. Data is modulated onto 16 tones, spaced at
112.5Hz intervals. The modulation rate of each tone is 75 Baud; the modulation type is differential qua-
ternary phase-shift keying (differential PSK4A).
Parameter
Value
Frequency range
HF
Operation modes
Half-duplex asynchronous adaptive ARQ
Modulation
Differential PSK4A; 16 tones
Symbol rate
16 x 75 Bd
AFC
In the range ±3100. automatic frequency control (AFC): +/-35 Hz
Bandwidth
1800 Hz
Receiver settings
DATA, CW, LSB or USB
Input format(s)
AF, IF