[AMPS] Receiver performance

Tom Rauch W8JI@contesting.com
Wed, 15 Mar 2000 14:54:10 -0500


> >That's because the filters you tested are after the receivers analog
> >selectivity. Look at the 756PRO reviews coming out, where it is compared
> >to things like the 1000MP.
> >
> 
> Which "that" are you referring to, Tom - the good low-noise performance of
> the selective DSP filters, or the ineffectiveness of the DSP noise
> reduction?

All of the above.

The noise reduction is ineffective, because the waveshape of noise 
and signals are virtually the same once the noise passes through a 
filter anywhere close to the same BW as the signal.

The DSP doesn't degrade S/N because the filter and AGC ahead of 
the DSP makes levels almost the same.

Because of that, the DSP can only do a good job as a notch or a 
passband filter. IF DSP's, with current technology in the equipment 
we buy, aren't much better.


73, Tom W8JI
w8ji@contesting.com

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