[CQ-Contest] Key Clicks.... Continuing Problem

[Jim Brown]

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