[A-DX] AM Stereo

[Roger]

Am 09.04.2017 um 16:41 schrieb Roger:
>
> Polarisationsdrehung der Wellen in der Ionosphäre, selektives Fading, 
> ohnehin begrenzter NF-Bereich - all das macht C-Quam über Raumwelle 
> dann eher weniger sinnvoll. 

So ähnlich ist das auch hier formuliert:

https://en.wikipedia.org/wiki/C-QUAM

"....Known problems

C-QUAM is not perfect, however, in large part because pre-AMAX it 
exhibited platform motion, with the audio "center" rocking back and 
forth as if changing the balance knob. This effect is potentially 
bothersome, especially in a moving vehicle where the received signal 
changes rapidly, and occupants (particularly the driver) would be more 
prone to its effects (this was an effect that happened primarily with 
skywave signals. Groundwave or local coverage usually did not suffer 
from this issue). This has been alleviated in subsequent revisions. 
Also, since some stereo information is contained in the sidebands, 
adjacent channel interference can cause problems. Finally, when only 
part of a sideband is attenuated (as often happens to skywave signals 
reflecting off the ionosphere), an effect known as selective fading, 
very unpleasant effects result; hence, the C-QUAM system is not often if 
ever used for shortwave broadcasting, nor by stations which receive a 
great deal of skywave interference.[citation needed]..."


Also über Groundwave ok,  über Raumwelle problematisch....



roger