Wavecom W40PC, Manual

Page: 91 / 264

WAVECOM Decoders v6.15 W40PC, W41PC, W51PC Advanced Topics
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VHF FSK ANALYSIS DIRECT (W51PC, W40PC)
The ”FSK Analysis Direct” mode is an important tool for the user to measure the radio
transmission properties of baudrate and frequency shift of
VHF-Direct signals
like
POCSAG, FLEX, etc. The magnitude of these properties may help identify the transmission
being monitored.
The Analysis is started with the input, gain, translation frequency etc. that was used, last time
in a VHF DIRECT mode. This selection is only available in the menu Preferences… the
"When selecting the toolbar "Analysis Buttons" start HF analysis mode" is not enabled. (See
Preferences…
on page 54).
To open the FSK Analysis window go to ”
VHF/UHF-Modes/Analysis DIRECT/FSK
Analysis ” or use the ”FSK Analysis” button. The baudrate and spectrum windows will open.
Because these kind of signals are not sent continuously, there is a need for a noise gate. The
status of it is displayed in the status bar. The noise gate examines the input signal and tries to
find out, if a valid signal is available which can be processed or if the input consists only of
noise.
If the noise gate has found a valid signal the baudrate and spectrum windows are updated.