[TenTec] [Orion] Orion II Noise Blankers

Grant Youngman nq5t at comcast.net
Sun Feb 26 18:22:58 EST 2006


 
> but I DO still hear a difference. I can only conclude from 
> this that there is no adaption component to the NR function, 
> and therefore the NR value is not controlling an adaption 
> rate, but something else, which sounds to me to be an 
> amplitude threshold.

We seem to be talking around each other, but there's no reason to believe NR
level is controlling some simple threshold. 

All I can suggest you do is take it up with Gary at T-T for a definitive
answer straight from the proverbial horses mouth :-)  

My take on it, based on experience and T-T's own description is that:

1.  It's adaptive
2.  It builds dynamic filters around signal spectral components
3.  Since the filters are dynamic, they are built and rebuilt as the
apparent spectral components change in the bandpass, at a rate determined by
the NR setting.  (I'm not saying this is precisely the mechanism, but it is
the effect of the mechanism.  T-T has not published, that I'm aware of, the
specific algorithms employed).
4.  The closer the signal amplitude gets to the noise level, the longer
adaption will take -- and in some cases, it may not take at all, in which
case, turn it off or turn down the THRESHOLD level or turn up the RF gain.
And if that doesn't work, then turn it off.
5.  It's primary function is to improve S/N ratio, not provide a "noise
free" environment for listening enjoyment :-)

Note that I am not making statements about how WELL it works, or doesn't.
Many seem to think it worked better in 1.371 and earlier releases than the
current realization in 2.xxx.

Grant/NQ5T




More information about the TenTec mailing list