[Elecraft] K3 Birdie Screenshots

[David Gilbert]

I've been beta testing using the new SIG RMV feature that Wayne 
developed for shifting birdies out of the passband, and I must say I'm 
extremely impressed.  It is very effective, and after addressing a 
handful of birdies I found it very easy to use as well.  I have been 
able to totally remove all of the birdies I considered even remotely an 
issue.  Where else would users be able to expect that kind of support??

I've received quite a lot of feedback (all of it constructive, by the 
way) , though, that suggests that I am either being overly critical 
regarding what I hear or that there may be a hardware problem (poor 
ground or other) with my particular K3.  I would happily recalibrate my 
thinking if it is the former, but I'd like to rule out the latter as 
well.  For that, we need a less subjective assessment.

With a standard 1/8" audio cable from the Line Out connector of the K3 
to the Line In connector on my computer sound card, together with the 
free and easy to use Spectrogram application 
(http://www.visualizationsoftware.com/gram.html), it is quite simple get 
a spectrum display of any birdie relative to the background noise in the 
passband.  Spectrogram even lets you take screenshots directly from 
within the application.  So I went back and found one of the birdies I 
had removed with SIG RMV and cleared the settings to let the birdie sing 
again.  I've uploaded the resulting Spectrogram screenshot to 
PhotoBucket, and it should be viewable simply by clicking on the link below.

http://i228.photobucket.com/albums/ee141/xazdave/K3Birdie-7124r890.jpg

The frequency for this particular birdie is 7124.890 KHz, the mode was 
LSB, the DSP passband was 2.2 KHz, the roofing filter was 2.8 Khz, the 
preamp was OFF, and the antenna connector was terminated in a precision 
50 ohm load.  The display indicates a birdie strength approximately 30 
db greater than the background audio noise level, although I wouldn't 
place too much credence in the accuracy of that.  This birdie was 
roughly S2 (two solid bars) on the K3 S-meter, and it's one of six 
birdies of similar strength I had on 40m before removing them with SIG RMV.

Comments or suggestions ...  even rude ones ;)  ....  would be 
appreciated, particularly if anyone is willing to compare a Spectrogram 
plot for the loudest birdie from their rig under similar conditions.

73,
Dave   AB7E








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