[BC] AM Carriers

[Tonne]

When referring to the signal representing the difference component
("L-R")  in the FM stereo system, it really is better to refer to it as
the  *subchannel*  as opposed to the  *subcarrier*.  The signal
which may be used to generate that subchannel signal, a "carrier"
at 38 kHz,  may very well be referred to as the subcarrier itself.
But it never appears in the final product.

In  the case of SCA, on the other hand, we have a steady signal
which is indeed a subcarrier.  To compound confusion, that
subcarrier and its sidebands occupy a region we can call the
subchannel.

I remember well how I was chastized by Jack Moseley when I
first addressed the FM stereo subchannel signal as a subcarrier.
"It's NOT a subCARRIER;  its a subCHANNEL!"
That was several years ago.

> A (sub)carrier is used when generating the AM sidebands of the L-R and 
> color signals, but the (sub)carrier itself is suppressed from the output 
> waveform. Only the sidebands are there.

Absolutely correct.

- JimT