User Manual

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upper limit). Starving the system of CPU resources manifests itself by the
computer becoming sluggish or possibly "freezing" entirely.
The first parameter, the IF bandwidth filter length, is the length of the first
filter in the digital path, which is responsible for much of the receiver
selectivity. The factory default length is 63. Reducing this value will
decrease the receiver selectivity and make the receiver more prone to
interference from nearby strong signals. However, for slower computers it
may be necessary to compromise on this figure if the demodulator appears
too slow (to the point of the panel "freezing" or drop-outs of audio) because
of insufficient CPU resources. If your CPU speed allows it, then we would
recommend to set this value to its maximum limit (255):
The Post-mixer filter length parameter refers to the post-mixer low-pass
filter, whose cut-off frequency is automatically related to the currently
selected IF bandwidth. For AM, AMN, AMS, CW, DSB, ISB, FM3, FM6 and
FMN modes, the post-mixer filters bandwidth is half of the IF bandwidth,
while for LSB and USB both bandwidths are equal to the IF bandwidth.
Again, if your CPU speed allows it, we would recommend to set this
parameter to its maximum value (255).
If you have a preference for particular IF bandwidths, you can associate
them with any of the ten preset buttons (located at the bottom of the
demodulator front panel) by double clicking the Bandwidth column of the IF
bandwidth presets table, and then typing in the numerical bandwidth value in