[TenTec] Questions about NR i.e. Orion

[Sinisa Hristov]

Bill Tippett wrote:


> NR effectiveness?  Measure MDS (Minimum Discernable
> Signal) with DSP BW = 100 Hz and NR Off.  Then
> switch NR On and measure it again.


MDS, S/N and similar measurements with NR on
must be peformed completely with the signal present,
and not by switching the signal on and off.

If the signal goes off, NR would readapt, so the sytem
being measured with signal off would not be the same
anymore as the system measured with signal on.

This means that the only way to do it is by spectral analysis,
with due care paid to subtle issuses like windowing functions,
bin size, etc. Using a voltmeter or level meter makes no sense,
even it is RMS responding.


73,

Sinisa  YT1NT, VE3EA