> Whatever happened after 1.371 destroyed NR - it is unusable
> or makes no difference at all in the present 2.xxx software.
> The NR button on the rig might as well not even be there.
Does anyone know what change was made in 1.372 that affected the behavior?
I looked through the History file on the v1, and nothing is jumping out at
me in the 1.372 changes. I believe that was where the Threshold adjustment
was linked to RF gain, but I don't see anything else other than a serial
control fix involving NR.
Early on with the v1 Orion that there were many complaints that punching in
NR made the radio get "noisier", but that was because threshold was being
reduced to the lowest value (increasing IF gain) automatically to maximize
effectiveness of the NR algorithms. So if you were running with Threshold
at 10 to quiet that day's background noise and then hit NR, the threshold
was dropped to 0.37 (or some other very low value) internally and the noise
level would come up. Something along those lines anyway. This was
perceived as 'NR increases the noise'. But the notion was that making the
radio "quiet" was not the objective -- improving SNNR was -- within the
bounds of the various constraints of the kind of noise, the signal level,
the DSP BW, yada yada.
There was also a view held by at least one member that somewhere around
1.339 something changed to make NR "just about totally ineffective when the
DSP BW is narrowed down to CW bandwidths".
Grant/NQ5T
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