Wavecom W74PC V8.7.0 - Manual (Page 108)

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Analysis Tools WAVECOM Decoder W74PC, W-PCI/e, W-CODE, W-CLOUD Manual V8.7.0
Tracking rate determines the sampling rate. The range is 1 - 15 ms; the default is 2 ms.
Double-clicking Filter inserts a low pass filter for filtering the tones. The value of the filter should be ad-
justed to avoid serious tone distortion. A rule-of-thumb value is 1.6 times the baud rate.
The filter range is 1 - 100 ms.
Using the Span menu, the resolution of the frequency axis may be increased. The steps are 3000 Hz (for
analogue selective calling systems), 1500, 600 and 300 Hz.
From the Center menu, the center frequency may be adjusted. It is important to readjust the center fre-
quency whenever the frequency (Span) axis is increased.
Several Color schemes are available through the right-click menu.
MFSK Code Check HF
MFSK code check is started by selecting the Analysis | MFSK Code Check button or from HF-Modes |
Analysis | MFSK Code Check.
The MFSK code check starts with default values.
In many cases the user needs to set the following values:
 center frequency
 baudrate (1/tone length)
 number of channels
 bandwidth (use the PB tuning to enter the correct bandwidth)
The center frequency and bandwidth can be set by using the cursors in the FFT Window, as shown below
or by selecting Center, in the Demodulator menu. The baud rate and the Number of Channels/Tones
can also be configured.
Note: The accuracy of the center frequency and shift settings are critical, and directly influence the quality
of the decoding.
After each configuration change, the MFSK code check automatically restarts with the new values. The
values of these parameters are displayed in the appropriate fields after changes have been made.