> Now the NR is absolutely no help at all on that same signal under the
> same conditions. When the DSP BW is that narrow, it doesn't work at
> all. ==========
> Why the apparent noise seemed to increase as
> you narrowed the BW below 500Hz is beyond me, hi. The main thing is
> that the signal became easier to copy. ==========
I don't know quite how to describe what I mean by "apparent noise".
What I observe is that at narrow bandwidths, turning on NR
increases the overall volume level of the noise, and changes it's
character to some extent (more LF components). Doesn't seem to
matter much what the NR level is set to. It's enough of an increase
to reach for the gain control over in some cases.
But at the same time very weak signals become, it seems to me,
easier to hear and copy. Once a signal is big enough to start to
wiggle the S-meter into the 2-3 range or so, the effect lessens
somewhat, and once a signal is big enough to hold the AGC at a
reasonable level it pretty much vanishes and I can't tell much
difference with NR on or off.
Maybe it has something to do with gain through the various DSP
processes ?? ... which means I don't have a clue :-)
Grant/NQ5T
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