There have been several editions of the Timewave software. The latest
one is distinctly better than the earlier versions in noise reduction
and AGC.
I find that sometimes the noise reduction and improvement in S/N by the
DSP is better when its given 2 KHz of noise rather than 500 Hz or less,
even when asking the DSP to cut the bandwidth to 50 Hz. Probably because
the NOISE in 2 KHz bandwidth is less well correlated than it is coming
through a 500 Hz filter and the noise reduction algorithm is based on
the quality of correlation, signals having great correlation, noise
having far less correlation. I'm sure some Kenwood 270 Hz CW filters as
used in the TS-430 that produce a tone from just noise would prevent the
DSP from reducing that noise.
73, Jerry, K0CQ
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Entire content copyright Dr. Gerald N. Johnson, electrical engineer.
Reproduction by permission only.
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