[Elecraft] K3: Optimizing TEXT DECode for CW

[David Wilburn]

Thanks for the info, I will give it a shot.  I have been doing my best 
to keep my eyes from straying to that and becoming a crutch.  But I 
have found it very handy, once a few letters get past me, or I get in 
over my head.  It is looking like my time for WPX this weekend will be 
hit or miss, but I will keep this in mind when dealing with those odd 
prefixes.


Dave Wilburn
K4DGW
K2/100 - S/N 5982
K3/100 - S/N 766

"For those who fought for it, freedom has a flavor the protected will 
never know."


KM5Q wrote:
> The K3 TEXT DEC system works well on CW signals that are above the noise 
> level, but to use it for weaker signals and noisy conditions requires 
> some understanding and technique. Here's what I learned.
> 
> The decoder gets its signal from the same trigger as the CWT indicator 
> bar. See for yourself -- When your display is in CWT mode, play with the 
> RF gain so the CWT bar goes on and off. The moment it disappears, the 
> decoding stops. As soon as the CWT bar flickers with noise, the decoder 
> TRIES  to read the on/off signal. If the CWT bar is responding to clean 
> code, you will get good text. If it isn't code, unfortunately, the 
> decoder tries anyway, and produces junk text.
> 
> If the CW signal is audible but is not stronger than the noise, the CWT 
> bar will flicker from the noise AND the CW, and the decoder will show 
> too much junk. Once you accept that, you can reduce frustration.
> 
> To minimize junk text from QRN, hold TEXT DEC, then adjust threshold 
> (thr ...) upward until it "squelches" the CWT bar. Now, The text decode 
> will work if there is CW signal above the noise.
> 
> But now, set the threshold a little lower, slightly too sensitive. This 
> will allow for varying conditions. When noise works the CWT bar, reduce 
> the RF GAIN until the bar disappears. This is how to fine-tune the 
> threshold quickly.
> 
> If you get static crashes or other erratic noise triggering the decode, 
> don't let  "IISKSK IEN SKSK" distract you.  Watch the CWT bar. Let THAT 
> tell you when to watch the text -- when it LOOKS like code rather than 
> noise.
> 
> Maybe future firmware will improve the decoder so it will ignore noise, 
> but for now, this is the best way I have found to use it.
> 
> Windy KM5Q
> Santa Fe, NM
> K3 #764
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