WiNRADiO G33DDC HF Receiver
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ADC are compared to a threshold value, and, if greater, then these samples
are zeroed.
The
Short Time DDC Averaging
method is preferable and will yield
improvement in most cases of atmospheric or man-made interference. It is
activated by pressing the
Enable DDC Averaging
button located under the
Noise Blanker
tab. If the instantaneous signal level at the input of the
demodulator exceeds the short-time average level by a user-adjustable
percentage amount, these signal samples will be replaced by zero values.
The
Sample Excess
setting should be adjusted as a compromise between the
noise blanking effect and the minimum acceptable distortion of the wanted
signal. The current value of the signal excess above the short-time average is
indicated in the associated display, to assist with the adjustment.
The
ADC Input Threshold
method is activated by pressing the
Enable ADC
Threshold
button. If the input at the ADC exceeds that defined by the
ADC
Threshold
control, the ADC input will be blanked. The current ADC level is
shown in the adjacent display to help with this adjustment. The maximum level
(100%) corresponds to the entire input range of the ADC.
Pause
The
Pause
facility makes it possible to temporarily stop the audio and resume
it at any time
– a useful function if one needs to get away from the receiver for
a while. This is a rather unique feature, specific to the
Excalibur Pro
, the
world’s first in professional HF receivers. While the receiver is pausing, the
entire incoming down-converted pre-demodulation signal is being stored in a
temporary buffer, so that other demodulation-related functions, such as the
audio filter or notch, can be still applied on the resumed signal.
l
The
Max. buffer time
setting determines the amount of disk space to be
allocated for the pause buffer, i.e. the maximum length of the pause. Any
signal that is older than the maximum buffer time allows will be discarded.
