Earl, K6SE, has posted results of his listening for key clicks with a K-2
transceiver as compared to his modified/unmodified 1000MP. His conclusion:
somebody needs to do a mod for the K-2.
Another conclusion: all currently available ham transceivers are equally
sinful regarding key clicks and it should be something that is cured by the
manufacturers in the product design phase rather than as post-purchase
mods. W8JI has made this point many times.
For example, the ARRL Lab in its extended report on the IC-746PRO included
something like eight separate keying sideband plots, using QSK and
semi-break-in and various rise times. Interestingly, there is no
significant difference in the sidebands (down by -35dB @ 1 kHz) no matter
what the variables. The 756PROII tested by ARRL showed a similar result,
as did the FT-1000MP Mark V Field, etc., etc. In fact, in an e-mail to me
some time back, Mike Tracy said that he had yet to find any transceiver he
had tested that he could point to as having clearly superior keying sidebands.
The ARRL lab's results seem to belie the reports of some hams who have
adjusted the CW rise times on their DSP-based Icoms up to 6 or 8 ms. If the
ARRL's keying sideband plots are to be believed, changing the rise times
has no impact on the sidebands, hence key clicks. What is it? A Gaussian
curve that is the ideal?
The only significant rig not yet tested is the Ten-Tec Orion and it will be
interesting to see if that rig does better at the ARRL lab than the -35dB
down @ 1 kHz that now seems to be the standard among ham transceivers.
73,
John, W3ULS
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