[TenTec] Noise Reduction Setting

[Merle Bone]

Gary - AA2IZ said:
"It further follows that the constant building and rebuilding that would be
done in qsk by such an automatic NR filter could easily lead to processing
artifacts.

If this is all Ten Tec is doing, I wish they would say so !"
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I think they did say so...............
Page 45 of the Orion Manual and page 45 of the Orion II Manual:

"If you turn the DSP NR on, and just cycle through the values looking for the "best" - nothing will happen.
Because the DSP NR builds a bandpass filter to automatically reduce noise, it produces the same effect 
as manually selecting a very narrow DSP passband filter."
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I don't think  Ten-Tec has been too secretive about the basic process used in Noise Reduction? I think maybe in the current V2 code the correct words might be "lowpass filter" (Maybe that is what the ARRL review said (QST September 2006 Paragraph Heading "Noisy Reduction")?

"- as if a low pass filter had been brought into play."



Actually I thought the QST review of he Orion II did a nice job of distinguishing it from the Orion starting with the paragraph heading:

"V1 vs V2" and continuing through "A Different Radio"



I agree with Grant and others that the performance of NR is at the margin. However, maybe unlike Grant, I have to fight for every 1 DB I can get

when working DX on 160M from St. Louis (I built a whole new 160M receive antenna for about 2DB improvement in signal to noise). I try to add together multiple 1 or 2 DB improvements to extend my receiving capability on 160M. Sometimes, depending on the noise, I find it easier to copy a signal with the bandpass set at 500Hz and the NR (V1.373b5) on 9 (Which will build a 400Hz filter around the signal - but with different skirt characteristics then the bandpass filter. I think that goes to the different "hearing and neurons" we all bring to the headphones (I noticed the ARRL reviewer also seemed to prefer the V1 noise reduction?). Maybe that is the meaning of "subjective."


73, Merle - W0EWM