On 11/14/2020 3:52 PM, Kenneth Wolff wrote:
> However, when the problem is the higher order harmonics of the baud
> rate, the attenuation doesn't change much from the 11th to 13th
> harmonic, and they do move out with speed.
For the dirty rigs, the effect of the keying wave-shape on bandwidth is
an order of magnitude greater than is the baud rate. I investigated that
with the K3 several years ago, and even with that very clean rig,
couldn't see anything until I got above 25 WPM. With dirtier rigs, I
wouldn't expect to see it under 40-45 WPM.
I believe Elecraft uses a sophisticated spectrum shaping DSP technique, > but the rest seem to use the equivalent of a simple RC filter and
that's > not good enough.
Yes, I believe that began with the K3, designed in 2007, and has carried
forward to their subsequent designs. Flex adopted it after their
6500-series rigs were tested by ARRL.
73, Jim K9YC
_______________________________________________
CQ-Contest mailing list
CQ-Contest@contesting.com
http://lists.contesting.com/mailman/listinfo/cq-contest
|