Classically, noise blankers were intended to remove
ignition noise which is short pulse, short duration,
high frequency.
John
--- Ron Castro <ronc@sonic.net> wrote:
> Great test, Lin! This confirms my more subjective
> observation that both the
> HW and SW NB's work extremely will on short-duration
> peak noise. Probably
> the stronger and shorter the peak, the better it
> works. Greater pulse-width
> duration noise, such as that from arcing power line
> insulators is another
> story...
>
> Ron N6AHA
>
> ----- Original Message -----
> From: "Lin Davis" <linbdavis@earthlink.net>
> To: "Discussion of Ten-Tec Equipment"
> <tentec@contesting.com>
> Sent: Saturday, February 25, 2006 2:34 PM
> Subject: Re: [TenTec] [Orion] Orion II Noise
> Blankers
>
>
> > After reading some some of the comments about the
> O2 noise blankers, I did
> > this
> > test:
> >
> > O2 settings:
> > AGC: slow (Hang: 2.02 sec, Decay: 5dB/s,
> Threshold: 0.37uV)
> > F= 21.3MHz, USB, BW=2100hz, PreAmp OFF, Atten:
> none.
> > Antenna: 10 foot piece of wire in ANT2 and within
> three feet of noise
> > source.
> >
> > I used a soldering iron for the noise source by
> switching it on and off
> > about 30
> > times for each of the settings below and recorded
> the highest S-meter
> > value
> > observed. (Probably not too good for the iron ;) )
> >
> > Results:
> >
> > NB S-METER Equiv. Input Total
> > HW SW Power (dBm) Reduction
> (dB)
> >
> > OFF OFF S9+55 -31 0
> > OFF 1 S9+30 -52 21
> > OFF 5 S9+20 -59 28
> > OFF 9 S9+20 -59 28
> > ON OFF S1.5 -94 63
> > ON 1 No Movement LT -101 GT 70
> > ON 5 No Movement LT -101 GT 70
> > ON 9 No Movement LT -101 GT 70
> >
> > Where:
> > LT = Less Than
> > GT = Greater Than
> >
> > The Equivalent Input Power values came from my
> S-meter calibration I did a
> > while
> > back with a precise RF generator (Agilent aka HP)
> >
> > Conclusion:
> > For this type of noise, the hardware blanker is
> very effective! The DSP
> > blanker
> > is less effective, but does reduce it
> signifigantly. Remember, a reduction
> > of
> > 70dB means the equivalent power was reduced by a
> factor of 10,000,000.
> >
> > I hope you found this informative....
> >
> > 73,
> > Lin
> > WB1AIW
> >
> >
> > Ronald Gorski wrote:
> >> At 03:55 PM 2/24/06 -0500, BobK8IA@aol.com wrote:
> >>
> >>
> >>>Both the hardware and software noise blankers in
> the Orion II dont seem
> >>>to
> >>>be doing much, if anything. The digital NR
> certainly operates as I can
> >>>hear
> >>>that one kick in.
> >>>
> >>>I did a master reset and no difference.
> >>>
> >>>Anyone else notice my problem?
> >>>
> >>>73, Bob K8IA
> >>>
> >>>_
> >>
> >> For me, the hardware NB works somewhat but the
> s/w NB does nothing. As I
> >> mentioned in a previous thread, the NR produces
> audio distortion.
> >> Ron N9AU
> >>
> >>
> >>
> >>
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>
>>>http://lists.contesting.com/mailman/listinfo/orion
> >>
> >>
> >>
> >>
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> >>
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> >>
> >>
> >
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> >
>
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