Robotron Pty Ltd WRG3P Manuel D’Utilisation

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Sound card control panels and their settings can be somewhat confusing.
They are also rather inconsistent from one version of Windows to another.

WiNRADiO G3 SERIES receivers require a full duplex sound card, meaning
that the card must be able to simultaneously process signals in two
directions (i.e. record and playback) at the same time. The majority of
modern Sound Blaster compatible cards are indeed like that. However,
some older cards may not be full duplex.

The Recording section of a sound card is used to input and digitize the IF
(Intermediate Frequency) signal arriving from the receiver (only the Right
channel is used, of the Left and Right stereo channels). The Playback
section is then used to output the demodulated audio signal to the
speaker(s).

For the WiNRADiO G3 SERIES application, there is a need to independently
control both sound card sections: The Recording section volume needs to
be adjusted to provide the correct IF signal level for the demodulation
process; the Playback section control is needed to be able to control the
speaker volume.

Typically, you would access the Playback volume control panel by clicking a
speaker icon in the Windows task bar. From this panel, you can get to the
Recording control panel by selecting Options | Properties | Recording in the
top bar menu.

However, the speaker icon may be missing. An alternative way of accessing
the Recording/Playback controls is via the Windows Control Panel. Here you
can also enable/disable the speaker icon.

The table on the following page shows how to enable/disable the speaker
icon, and how to get to the recording/playback controls from within the
Windows control panel. The methods vary depending on the version of
Windows you are using.