[Elecraft] Rick Tavan's excellent K3 article

[Rick Tavan N6XI]

Yes, my comments in that article were subjective. The test labs will run
receiver recovery tests that I'm not equipped to do.

I ran an informal test with N6TV a few months ago while the K3 keying
firmware was still in development. I sent a string of dits on the K3 and he
tried to break me with one (1) dit at the same speed. I used fast AGC but
did not record the CW rise time or AGC parameters in effect at the time. At
20 wpm it was easy. At 30 it was hard, sometimes taking multiple breaking
dits or a dah. There were a few artifacts back then. The QSK improved
considerably after that as the firmware reached production release but I
haven't repeated the test.

Right now, at 100W out and S2 line noise, I can hear the noise clearly while
sending at 30 WPM. It sounds like a code practice oscillator and is clearly
superior to the TS-930S sitting next to it. (The 930 has some clicky
artifacts that don't exist on the K3.) At 40 WPM, the received noise is
almost gone behind a string of dits but you can still hear it between
letters.  Sorry, this is still subjective. If you want to do some on-the-air
tests, I'll be happy to help.

Of course, any radio will have its QSK degraded when there are ionospheric
echos. We should be so lucky these days!

73,

/Rick N6XI

------ N1EU Wrote -------

I agree that's it's generally a well written and informative article.
However, I couldn't help raising my eyebrows at "the QSK provides true
between-dots receive at high speed" - doesn't really say much.  Is
that 20wpm or 45wpm?

Have any of the K3 users really sat down and tested the QSK and can
report at how high a keying speed the K3 receiver recovers between
dits?  The cw rise time and rx AGC settings used for the test would
also be useful to know.

Thanks & 73,
Barry N1EU