Questions about Jason.]

[Andre Kesteloot]

Rik Strobbe wrote:

> >Rik ON7YD is much expert than me in QRSS speed calculations, but let's try :
> >suppose I want to send   CQ DE I2PHD
> >Unless my computation is wrong, that amounts to a total of 106 dot lengths,
> >so the time needed is the following :
> >QRSS3     106 x 3   = 318 seconds, i.e.   5 minutes, 18 seconds
> >QRSS10   106 x 10 = 1060 seconds, i.e. 17 minutes, 40 seconds
> >QRSS60   106 x 60 = 6360 seconds, i.e. 1 hour, 46 minutes
> >Jason         12 characters / 2.5  =  4 minutes, 48 seconds
> >
> >I leave to Rik the computation for DFCW...
>
> In DFCW it would be a length of 40 dots so :
> DFCW3 = 2 min 0 sec
> DFCW10 = 6 min 40 sec
> DFCW60 = 40 min
>
> If we simplify a bit and assume that SNR is only determined by the
> dotlength we would have to compare Jason with QRSS12 or DFCW12 :
> QRSS12 = 21 min 12 sec
> DFCW12 = 8 min 0 sec
> Jason = 4 min 24 sec (I count only 11 characters)
>
> The other way arround, if we want to transmit the text at the same speed as
> Jason we would need to use QRSS at 2.5 sec/dot or DFCW at 6.6 sec/dot.
> This would make QRSS about 6.8dB and DFCW about 2.6dB inferior to Jason.
> In the real world the differences will be a bit less since Jason is using a
> larger bandwidth.
>
> 73, Rik  ON7YD