User Manual

WiNRADiO G3XX User’s Manual

This is useful to establish the background noise level when no signal is

received, so that the AF squelch value could be set suitably lower than the

background noise. When a frequency-modulated signal is received, the noise

should drop below the AF Squelch level, which will activate the audio. Note

that the noise level also depends on the IF bandwidth setting: The wider this

setting, the higher the noise level.

Notch Filter

The notch filter is a band-stop filter which can be used to minimize the effects

of interference falling inside or near a received station’s spectrum. The filter is

activated by pressing the Notch Filter button. The centre frequency and the

bandwidth can be adjusted using the correspondingly named controls:

For both controls, the same usage rules apply as with the IF

bandwidth setting, i.e. the values can be changed by direct

manual entry, or finely adjusted by using the up/down cursor

keys, or by dragging the slider between them.

Another way of changing the Notch Filter parameters is by

dragging the stopband of the filter (a blue shaded area) with the

mouse.

The stopband width can be adjusted by dragging the edges, while the centre

frequency can be changed by dragging the centre line, which makes it

possible to conveniently position the filter stopband over the interfering signal.

Did you know?

In addition to the above notch filter which operates on the undemodulated

intermediate frequency signal, you can also have audio notch filtering

(including auto-notch) in the optional Advanced Digital Suite plug-in, available

for the G3XX receiver. This also features numerous user-adjustable audio

filters and various other signal conditioning, noise-reduction, decoding and

analysis facilities. See www.winradio.com/ads for more details.