This is misinformation that can be harmful to newbies or folks that don't have the knowledge of about how the two different types of signals (FSK versus AFSK) are generated.
At the most basic level, if you look at the math involved in generating the two types of signals, i.e., FSK versus AFSK, you will see that AFSK has signal components close to the operating frequency that FSK doesn't have. These components are commonly called 'opposite sideband' and 'suppressed carrier'. Depending on the quality of the transmitter and the method of SSB generation, AFSK will have these components more or less suppressed but they are still there. To say they can not be distinguished means your measurement criteria and equipment are not capable of seeing the differences. It doesn't mean the signals are identical. That is why there are different emission designators for the two types of signals. I will admit that at the most coarse level of examination these two signals look the same, that is, individual carriers (at any one time) at a given frequency. However, a more granular examination will show that they are not identical. Jim WA0LYK --- In digitalradio@yahoogroups.com, Ralph Mowery <[EMAIL PROTECTED]> wrote: > > You do not understand what hapens when you send audio > tones for rtty into a ssb transmitter. The end result > of what comes out of the transmitter can not be > distinguished from a true FSK transmitter. That means > in effect the transmitter is not putting out AFSK but > just FSK. On todays modern transceivers many of them > use an audio tone in the USB mode to generate CW. > In effect you are really transmitting FSK and not > AFSK. > > If you switch the rig (as many multimode rigs can) to > AM or FM then you are transmitting AFSK. This makes > it not legal in the data frequencies of the low bands. > > > > > > ____________________________________________________________________________________ > It's here! Your new message! > Get new email alerts with the free Yahoo! Toolbar. > http://tools.search.yahoo.com/toolbar/features/mail/ >
