Wavecom W40PC, Manual

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Transmission Modes WAVECOM Decoders v6.15 W40PC, W41PC, W51PC
Baudrate(s) 100, 150 and 200 Baud, variable 30-650 Baud
Modulation SSB or DIRECT-FSK
Receiver settings CW, LSB or USB
Signal source(s) AF, HF or IF
Alphabet Sitor
POL-ARQ operates at a speed of 100 and 200 Baud on the radio link.
To synchronize to this mode select a baudrate. By selecting the “
Auto
” button, the automatic
determination of center frequency, shift frequency and baud rate is performed. Signal polarity
(LSB or USB sidebands) is automatically detected.
POL-ARQ is a full duplex system with two transmitting frequencies. The system is based on
the Sitor-ARQ alphabet. This alphabet having a 4:3 mark-space ratio allows error detection.
Like all duplex systems, POL-ARQ initiates a request for repetition cycle (RQ) when
transmission errors occur.
To maintain synchronization between the two duplex stations, both transmitters operate
continuously. If no data is transmitted an idle bit pattern is sent.
At 100 Baud the last three characters are repeated after the RQ character. At 200 Baud the last
four characters are repeated (5 character repetition cycle). Due to mode characteristics the
character repetition cycle must be controlled manually.
PRESS-FAX
Parameter Value
Frequency range HF
System FAX
Drum speed 60, 90, 120, 180 and 240 RPM
Index of Cooperation (IOC) IOC 288, 352 and 576
Modulation SSB or DIRECT-FSK
Receiver settings CW, LSB or USB
Signal source(s) AF, HF or IF
The transmission of press fax images on short-wave is based on gray levels and specific IOC
values. A number of IOC assignments were modified for press image transmissions. These
special characteristics are taken into account in the PRESS-FAX software.
If the “Auto” function is selected the software waits for the IOC identifier and synchronization
sequence. Both parameters are only transmitted at the start of an image and hence capture will
only start when the next image occurs. By selecting “
PRESS-FAX “ the decoding starts
immediately and the drum speed and IOC can be programmed manually via the “
Drum
speed
” and “
IOC
” items in the “Demodulator” menu. The selected parameters are displayed
in the decoder status bar.
The decoder allows a continuous and smooth alignment of the image as it is being received via
the “
Fine Speed ” item in the “Options” menu. By using the “ Phase ” item in the “Options”
menu the entire image can be shifted into the correct position.
To enhance the interpretation of gray-scale images, a false color option is available. Right-
click on the image to open the "
Zoom"
menu and from the bottom part select a color scheme.
A checkmark is placed to the left of the selection.
PSK-31
Parameter Value