Sangean PR-D3 Mode D'emploi page 15

Stereo/Mono switching
If the FM radio station via the headphone has a weak signal, some
hiss may be audible. It is possible to reduce this hiss by forcing the
radio to play the station in mono rather than stereo.
. Tune to the required FM station as previously described.
2. Press and release the AM NARR/FM MONO button to switch to
mono mode. The red light indicator will illuminate and the
symbol will disappear from the display.
3. Press the same button again to return to stereo operation.
Note:
FM stereo is only available when using headphones.
AM bandwidth narrowing
In order to obtain better reception, your radio has the function to
narrow the AM bandwidth to filter the hiss from the high frequency.
. Select the AM band by pressing the Band button.
2. Press the AM NARR/FM MONO button to activate the function
and the red light indicator will illuminate.
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