Jukka has based all his comments on something he recently read on Nabble
... apparently without noticing that the reference was originally posted
way back in 2009 (seven years ago). In addition, it appears that he
didn't even understand the post, which states that the K3 originally had
a pretty soft rise/fall time of
8 msec which was SHORTENED to about 2.5 msec after Elecraft implemented
the special shaped waveform that is still in use today.
In other words, the K3 never had harsh keying ... even before the
firmware change. Jukka has got it all backwards.
Dave AB7E
Dave AB7E
On 2/24/2016 4:35 PM, Jim Brown wrote:
On Wed,2/24/2016 6:27 AM, Jukka Klemola wrote:
I am going to think a little and make a write up somewhere on the
subject
Rather than "think," it would probably be far better if you were to
STUDY the documentation for modern radios and the impartial testing
done by ARRL Labs, and published on their website. I have done that
quite extensively, and have written it up in k9yc.com/TXNoise.pdf
These are FACTS that I have taken the time to learn, not opinions.
Again, you speak of firmware upgrades for the K3 "solving" a problem
with clicks. I've been using K3s with legal limit amps since 2008. I
do not recall ever having an issue with clicks -- if I did, K6XX, who
lives five miles from me, would have told me! Again, you have bad
information.
Beginning with the K3 and all of its accessories, firmware upgrades
are nearly automatic. The firmware update utility (one for Windoze and
one for Mac) queries the radio via a serial or USB port, queries the
website and downloads the latest firmware, asks if you want to update,
and if you say yes, it does that.
I first published TXNoise about 18 months ago. It clearly showed that
Yaesu radios were by far the dirtiest on CW, with very excessive
clicks and phase noise. A few months later, they issued a firmware
update that significantly improved the keying performance of the
FTDX5000 and others in that family. Likewise, ARRL's review of the
Flex 6500 and 6700 SDRs showed really awful CW bandwidth. A few months
later, Flex issued a firmware update that significantly improved the
keying performance.
In TXNoise, I noted the connection between rise/fall time and keying
bandwidth, and stated the simple rule that if it is adjustable, slower
produces the cleanest result.
I would like to update TXNoise with results for the 6500/6700 radios
after their firmware upgrade, but have so far been unsuccessful in
having an owner loan his rig for measurement. N6TA loaned his FTDX5000
for before and after measurements, and they are on my website.
http://k9yc.com/P3_Spectrum_Measurements.pdf
73, Jim K9YC
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