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Transmission Modes WAVECOM Decoder W74PC, W-PCI/e, W-CODE, W-CLOUD Manual V9.1.0
Reference tone on 1000 Hz
The coded message is transmitted using Frequency Shift Keying, the baud rate is 300 baud, the mark-
frequency is 2225 Hz, and the space-frequency 2025 Hz.
The display shows the information of each packet on a single line.
The first packet, sent at the 31st second of each minute, provides the year, the delta-information and the
daylight saving pattern code.
The following packets, sent between seconds 32 and 39, provide day, hour, minute and actual second.
The user can specify the polarity of the received signal, i.e., NOR(mal) or INV(erse).
CIS-11
CIS-11 transmissions are mainly in the Russian M2 (3-SHIFT-CYR) adaptation of the ITA-2 alphabet. It is
a full-duplex system with two transmission frequencies.
100 Bd, variable 30-650 Baud
CIS-11 operates at a Symbol rate of 100 Bd on the radio link.
Synchronization for the CIS-11 mode is started with the selection of a baud rate. An AUTO start causes
the automatic determination of the frequency shift and baud rate to be executed first. The signal polarity
(USB or LSB sidebands) is automatically detected.
The CIS-11 data format is 11 bits wide. Data bits 1 - 5 contain the M2 character. The data bits are ar-
ranged in reverse order if compared to normal M2 systems. Bits 6 and 7 specify the system state as well
as the alphabet.
Bits 8 - 11 handle error detection. The four test bits allow the position of a bit in error to be computed and
then to be corrected. The value of the parity bits is obtained by calculating the modulo-2 sum of the bina-
ry weights of the respective information bits.
To maintain synchronization between the two duplex stations, both transmitters operate continuously and
transmit idle characters if no traffic is transferred.
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