[CQ-Contest] WPX CW Signal Quality Concerns

[Jim Brown]

On 6/8/2020 7:59 AM, Jeff Blaine wrote:
> Don't stop there Jim, maybe you could provide a supplemental list that 
> specifically calls out the rigs that are acceptable in this respect. And 
> perhaps your objective metric that provides the dividing line between 
> good and bad.

With what funding? Isn't that the job of our organizations like ARRL and 
RSGB?
> 
> So far, you state the FT2K as belonging in the "bad" (replace) category, 

On the basis of 6 msec being the slowest possible rise time. That's not 
one of the rigs in my 2014 analysis of ARRL Lab data. The radios I chose 
to compare were those used at the recent WRTC and then popular at lower 
cost.

> and from prior statements on the topic, the K3 falls in the "good" 
> category.  Lot of other radios out there needing your judgement and 
> owners needing your advice.

All of the Elecraft rigs since 2008 are "good" from a keying bandwidth 
point of view. They achieve rise time of about 2.5 msec, but without the 
clicks of the simpler "time-constant" keying of the other rigs, and 
they've said that the new K4 uses the same technique. Although I haven't 
been able to get one to measure, it's my understanding that Flex 
6000-series adopted shaping inspired by the Elecraft method, but not 
before ARRL Labs tested one that wasn't at all good. There are a lot of 
those radios in use by contesters, and I've yet to hear clicks from them.

73, Jim K9YC