User Manual

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Firstly, in the sound card Playback volume control panel, the software
mutes the sound card input line the receiver is actually connected to. This is
the same line as selected in the WiNRADiO G303 demodulator Setup, i.e.
usually, this will be Line or Microphone input.
This may seem a bit unexpected: Why are we muting the input line? This is
because the signal coming from the receiver is not an audio signal, but
rather the intermediate frequency signal. It needs to be processed
(demodulated) by the PC first, before it is output back to the sound card.
That’s also why the sound card needs to be full duplex, to allow for such
simultaneous input/output processing.
Failure to mute this line would cause a high-pitched intermediate frequency
sound to be combined with the demodulated signal.
To see how the line is muted, click on the speaker icon in the task bar in the
bottom, to bring up the sound card Volume Control panel (consult
Appendix B – Sound Card Controls if you have difficulties locating the
sound card settings):
The same line will be selected in the Recording Control of the sound card
control panel. To get there, you need to select Options | Properties |
Recording in the top bar menu of the Volume Control panel.