[Elecraft] a two-fer posting: K2 SSB audio, and K1 tuning range observations

[Steve Jackson]

Two comments:

A recent query... "I am considering purchasing a K2
and want to know how well the SSB transmit audio
works. How clear is it on the receiving end? "

I made a posting on eHam's reviews about this some
time ago.  The K2's SSB TX is NOTABLY excellent, both
from a technical vantage (carrier suppression,
linearity, group delay, etc.) as well as from a
qualitative vantage.  

If there are variances from such realized performance
they are a function of incorrect alignment, incorrect
assembly, or some other non-design-related phenomena. 
I have designed and built several phse-type and
filter-type SSB exciters, and the one in the K2 is
superior to any that I have built, **even for my own
use.**  In fact, only a DSP-based SSB generation
mechanism (such as the one in my IC-756PRO II) tops
the relative performance of the K2 on SSB TX ... and
not by a lot.

Remember, at the edge of such qualitative analyses,
variables like room acoustics and microphone response,
to say nothing of your own voice and enunciation,
provide much greater coefficients of "quality" that
the electronics do.  I use an amplified Astatic D-104
(TUG9 stand; separate battery supply) and have
carefully adjusted the gain stage for nominal
amplification, equalling the Elecraft hand mic which I
also own.  All modesty aside, I sound like FM when I
transmit 'phone on my K2.

You can, too.


Second comment:  over the several years I have been on
this reflector, I've see much commentary on the
selection of the K1 tuning range.  Elecraft supplies
parts for two different ranges / tuning rates.

Two observations come to mind that I have rarely, if
ever, seen posted here:  

(A) the capacitors supplied actually offer tuning
ranges in excess of those specified, perhaps by
10-15%.  

(B) there is no law that says if your personal parts
supply includes capacitors of equal or greater thermal
stability to that of the Elecraft parts, that you
can't install your OWN cap of a value BETWEEN the two
offered!  

That's what I did.  On 20 meters, for example, I can
tune from 13.993 to 14.109 MHz or so ... with
excellent linearity and a barely-noticeable tuning
step using the stock pot.

73  Steve KZ1X/4
K2 #771
K1 #1181





	
		
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