Hi Bill, 
Thanks for the comments!

> IMHO any setting that increases the number of bad decodes is not worth 
> the time saved unless that time is in danger of being longer than the 
> available time before the next decode cycle. I say this because 
> unfiltered bad decodes cause erroneous outliers, e.g. open path plots, 
> that will easily mislead naive users trying to interpret result data.

Yes, I agree that bad decodes have annoying consequences - but as you said, 
many of them can be taken care of by better validation of the decoded callsign 
and grid. 

I don’t think that time is a factor --- the decoder is quite fast now and even 
the smallest computers should have no trouble keeping up with a single instance 
of wspr. My observation, based on a small set of tests, is that the bias 
setting has a negligible impact on the running time. Changing the maximum cycle 
count would have a much more direct impact on running time.

My preference is to skootch the bias down a bit to make the decoder more 
agressive so that I get to see the 20 or so extra spots per hour that I 
wouldn’t have seen otherwise.  I’m willing to have to recognize and discard one 
or two bad spots in order to maximize the probability of seeing that exciting 
long-path, or TEP, or double hop Es or (fill in the blank) spot. 

Please let me know if you think that I’ve set the default bias too far on the 
aggressive side. For the record, setting it to something like 0.48 should make 
the performance roughly the same as what we had before. Setting it to 0.5 makes 
it slightly more conservative than what we had before.

On a separate matter, I've measured the frequency of the transmitted WSPR 
signals using a separate receiver and this latest decoder. The transmitted 
signal measures 0.2-0.3 Hz high (the decoder has 0.1 Hz resolution), as 
expected, given the 1 Hz resolution of the Modulator. Is this something that 
would be easy to change? I have to admit that it bothers me to be transmitting 
0.1973 Hz off frequency!

73 Steve k9an
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