[Lf] Jason test sigs]

[Andre Kesteloot]

Alberto di Bene wrote:

> James Moritz wrote:
>
> >  If the centre frequency is
> > F, and the spacing between tones is f, the possible tone frequencies are F
> > +/- (n-0.5)*f where n is an integer from 1...16. Therefore there are 32
> > possible equally-spaced tone frequencies from F-15.5f to F+15.5f. Is this
> > correct?
> >
>
> Hi Jim and the group,
>
>   yes, correct, that's how the information is encoded in Jason.
> There is another possible format, which has pros and cons.
> It has been also suggested by Stewart Nelson. I had initially,
> when designing Jason, dismissed it, but now I am here asking
> your collective opinion.
>
> Presently only the absolute value of the frequency delta is used
> to encode the information. If  I use also the sign, I have this results :
>
> -Pros  The band occupied is nearly halved, from 32 slots, it goes
>            down to 17 slots.
>
> -Cons The system is no more sideband independent. Now it is
>            immaterial whether the RX is set to LSB or USB.
>            This would not be any more the case with the alternate scheme.
>
> So, what would all you judge more important, sideband independence,
> or bandwidth used ? Your vote will decide the final format for Jason.
>
> 73  Alberto  I2PHD