WiNRADiO G33DDC User’s Manual
81
When dithering is selected, it reduces the amount of spurious signals caused
by the action of the analog-to-digital converter (ADC). These are rather
negligible in the
Excalibur Pro
, but they do exist. This is done at the expense
of a slight increase of the noise floor.
MW Filter
The
MW filter
(medium wave filter) is a high-pass filter with a cut-off frequency
of approximately 1.8 MHz. When engaged using the
MW filter
button, it
significantly reduces sensitivity in the region under 1.8 MHz, i.e. the region of
AM broadcast radio.
The purpose of this function is to reduce interference from strong broadcast
stations and so improve the reception of weak shortwave signals.
RF Filter
The
RF filter
is a bank of mostly band-pass preselector filters whose cut-off
frequencies are user-adjustable.
When engaged, and the lower and upper cut-off frequencies are set, the
adjacent frequencies will be attenuated, to reduce susceptibility to interference
on the adjacent bands. The cut-off frequencies can be adjusted manually (119
filter combinations are possible, out of which 91 are band-pass, 14 low-pass
and 14 high-pass).
If you engage the
Auto
button, the software will automatically select an
optimum filter combination for the currently tuned frequency. Such automatic
switch-over will usually occur somewhat earlier than at the exact cut-off
frequency, in order for the signal to remain at the flat portion of the filter
passband.
