[Elecraft] K3 Audio Measurements and Artifacts

[Jack Smith]

I've completed a few K3 receiver audio output measurements today, and 
added a new page with the data.
http://www.cliftonlaboratories.com/elecraft_k3_receive_audio.htm

I found some curious artifacts in the audio output, including some 
signal related artifacts around 12 KHz, and at 3.9 and 7.8 KHz. I don't 
know if these are unique to my K3, or to my test setup, so I welcome 
other observations.

If these artifacts are not unique  to my K3 and/or test setup, it might 
explain some oddities heard in the audio, if your high frequency hearing 
is good and if you use headphones capable of 20 KHz reproduction. 
Although my headphones are good up to that range, too many years of 
listening to loud CW mean that my hearing has a cutoff sufficiently low 
so that none of these oddities make it into my wetware audio processor.

I've also made an automated GIF image of spectrum analysis images for 
LIN OUT settings from 2 to 100, as well as a few other points that may 
be of interest.

Jack K8ZOA
www.cliftonlaboratories.com