[Elecraft] K3 and Datamodes

[Julian G4ILO]

On 6/6/07, Vic K2VCO <vic at rakefet.com> wrote:

> The point that I'm (still) missing is how is a good AFSK signal is
> supposed to be different from a 'true FSK' signal as G4ILO suggested.

I didn't suggest it was different. I was suggesting that it was easier
to tune because, as Bob said in his reply, you can fine-tune by
clicking on the waterfall display which adjusts the mark-space tones,
instead of having to take your hands off the keyboard or mouse and
twiddle the receiver knob.

Greg makes a fair point about FSK potentially being cleaner, but I
would be interested to know if that is really the case. Certainly if
the audio was overdriving the transmitter you could radiate a dirty
signal, but if the system is properly set up would there be a
noticeable difference?

With FSK there might be the possibility of clicks or artefacts
occurring during the change between mark and space. A
software-produced AFSK could ensure that the transitions occur when
the wave passes through zero, which would result in a cleaner signal,
surely?

Whether that's true or not, I would have thought the usability
benefits of the AFSK method, especially in a contest situation, would
outweigh any theoretical advantages of FSK, which are probably
undetectable on the air, even if they are measurable.
--
Julian, G4ILO
G4ILO's Shack: www.g4ilo.com
K2 s/n: 392  K3 s/n: ???