On 4/13/2014 8:47 AM, Fred Smith wrote:
I have a newer Icom here and might have to debate the receiver issue and I'm half deaf. The Icom does have both CW and SSB filters/D-Star in it but when it comes to weak signal the K3 is superior as is the KX3.
A few decades ago, Richard Heyser, one of the wise men at JPL who helped put us in space said about audio systems that "attempting to describe an audio system using only frequency response was equivalent to attempting to write poetry with only one word in our vocabulary."
The quality of a radio is defined by many things, some of which have numbers tied to them and some of which do not. Several months ago, a published table (was it from Radcom?) was posted here comparing the transmitted phase noise of a dozen or more popular rigs, including the K3, KX3, one or more Flex radios. A similar study could (and should) be published to address clicks and TX IMD, and I think Rob Sherwood has tackled much of that. TX and RX phase noise is a big deal in contests, and even in big DX pileups -- it's not unusual to hear (and see a dirty TX on a P3) splatter or click down onto the DX frequency! KE1B is about 8 miles from me using an ICOM 7600 to drive a big amp. His clicks and phase noise wipe out about four times as much of the band as K6XX, who is only 3 miles away but uses K3s to drive tube amps.
FCC Rules place limits on signal purity that, if you study them and do the math, cannot be met by most rigs driving most solid state power amps to full power. A K3 driving a properly tuned tube amp does satisfy those Rules. Some ICOM rigs (the 7600 is one of them) allows the user to vary the keying rise time over a wide range, most settings are very clicky, including the default. I know this because I made a carefully controlled set of on-the-air measurements of one owned by a neighbor.
All of this is apart from ergonomics issues, about which Fred has written the book. :)
73, Jim K9YC ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
