Help with IF Noise, DSP Noise, NR settings

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Help with IF Noise, DSP Noise, NR settings

KC6CNN
Hello Everyone.
I was listening this morning to a few week signals and lots of static.
I was playing with the IF Noise Blanker and DSP Noise Blanker and NR
Settings to find what would take out the static but leave the CW tone.
I could not find a good setting.
Is there any information or help in finding a good setting for these.

Thanks in advance.
Gerald.




-----
KC6CNN - Gerald
K3 # 6294
KX3 # 757
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KC6CNN - Gerald
K3 # 6294
KX3 # 757
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Re: Help with IF Noise, DSP Noise, NR settings

w5sum
Going from a TenTec Orion to the K3 the only disappointing thing to me was the difficulty in using the NB and NR and DSP. I finally just gave up. If I can hear it I work it. If I don’t I don’t.

W5SUM

Sent from my iPhone

> On Jun 13, 2019, at 5:04 AM, KC6CNN <[hidden email]> wrote:
>
> Hello Everyone.
> I was listening this morning to a few week signals and lots of static.
> I was playing with the IF Noise Blanker and DSP Noise Blanker and NR
> Settings to find what would take out the static but leave the CW tone.
> I could not find a good setting.
> Is there any information or help in finding a good setting for these.
>
> Thanks in advance.
> Gerald.
>
>
>
>
> -----
> KC6CNN - Gerald
> K3 # 6294
> KX3 # 757
> --
> Sent from: http://elecraft.365791.n2.nabble.com/
> ______________________________________________________________
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> Please help support this email list: http://www.qsl.net/donate.html
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Re: Help with IF Noise, DSP Noise, NR settings

Nr4c
This is not an easy thing.

First, are you hearing general band noise, a constant “ shhhhhhhhhhhh” or pulses as in lightning, power line, or ignition type noise.

For band noise, the NR will be your best solution. Experiment, but don’t go too deep. Deep settings will distort and make it sound like you’re underwater.

For the pulse noises, try IF first, again don’t use extreme settings. If this doesn’t work, try the DSP settings and see if this will work.

I have NB set to Med4. NR is set to F1-3.  

YMMV.

Have fun!

Sent from my iPhone
...nr4c. bill


> On Jun 13, 2019, at 6:51 AM, Ronnie Hull <[hidden email]> wrote:
>
> Going from a TenTec Orion to the K3 the only disappointing thing to me was the difficulty in using the NB and NR and DSP. I finally just gave up. If I can hear it I work it. If I don’t I don’t.
>
> W5SUM
>
> Sent from my iPhone
>
>> On Jun 13, 2019, at 5:04 AM, KC6CNN <[hidden email]> wrote:
>>
>> Hello Everyone.
>> I was listening this morning to a few week signals and lots of static.
>> I was playing with the IF Noise Blanker and DSP Noise Blanker and NR
>> Settings to find what would take out the static but leave the CW tone.
>> I could not find a good setting.
>> Is there any information or help in finding a good setting for these.
>>
>> Thanks in advance.
>> Gerald.
>>
>>
>>
>>
>> -----
>> KC6CNN - Gerald
>> K3 # 6294
>> KX3 # 757
>> --
>> Sent from: http://elecraft.365791.n2.nabble.com/
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:[hidden email]
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>> Message delivered to [hidden email]
>
> ______________________________________________________________
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Re: Help with IF Noise, DSP Noise, NR settings

Bob McGraw - K4TAX
The Noise Blanker only affects repetitive pulse noise such as ignition
type noise.  Lightning and atmospheric is random noise. As to the Noise
Reduction, I find that use of the Attenuation and RF Gain control is far
superior to using DSP systems.  Also remember it is Noise Reduction and
not noise elimination as many seem would like to believe.  If one
realized 6 dB of noise reduction using the system that's good.   At the
same time, any noise reduction system will add distortion to a SSB or CW
signal.

 From very authoritative source, the optimum receiver performance
configuration is to have the no signal band noise about 10 dB above the
noise floor of the receiver.    Since we can't change the noise floor of
the receiver, the option is to change the incoming level of the noise as
presented to the receiver input. The K3S receiver noise floor is about
-135 dBM.   If one has a no signal band noise of S-5 or -97 dBm, the
difference is 38 dB. This says we need 28 dB of Attenuation and RF Gain
reduction.    That would be 15 dB of Attenuation and about 2 S units of
RF Gain reduction or 10 dB of Attenuation and about 3 S units of RF Gain
reduction.     This in no way changes the sensitivity of  the receiver
nor does it impede the ability to hear weak signals. Unfortunately many
hams belie that more gain is needed to hear weak signals.   With
receivers of 50+ years ago often the receiver noise exceeded the band
noise.  That however is not true with today's modern receivers.

As to using the Noise Reduction,  I do not use it at all for SSB and for
CW.   If  I do use it I find  F1 and a value of 1 to 3 about all I'm
willing to accept.  Of course the type and magnitude of the noise does
require different settings.

If I use the Noise Blanker I find it necessary to first set the IF NB to
OFF.  Then adjust the DSP through its values to get what seems to be the
best result.  Remember the value.  Then set the DSP NB to OFF.   Then to
the IF noise adjustment and find what seems to be the best result.  
Leave it at that and then back to the DSP Noise blanker and set it to
the previous obtained value.    This optimized them individually.   I've
not been successful in trying to adjust both at the same time.    And
remember it only works on repetitive noise such as ignition noise or
line noise and not random atmospheric noise.

The receiver gain method works best.   Hope this helps.

73

Bob, K4TAX



On 6/13/2019 6:43 AM, Nr4c wrote:

> This is not an easy thing.
>
> First, are you hearing general band noise, a constant “ shhhhhhhhhhhh” or pulses as in lightning, power line, or ignition type noise.
>
> For band noise, the NR will be your best solution. Experiment, but don’t go too deep. Deep settings will distort and make it sound like you’re underwater.
>
> For the pulse noises, try IF first, again don’t use extreme settings. If this doesn’t work, try the DSP settings and see if this will work.
>
> I have NB set to Med4. NR is set to F1-3.
>
> YMMV.
>
> Have fun!
>
> Sent from my iPhone
> ...nr4c. bill
>
>

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Re: Help with IF Noise, DSP Noise, NR settings

gt-i
My fav NR setting is F1-4.

In addition to Bobs excellent explanation about noise levels and
sensitivity, also consider adapting the AGC settings.  Don's article
about AGC is  very helpful: http://www.w3fpr.com/K3_AGC.htm

In some situations I even turn AGC off.

gd dx!

Gernot DF5RF



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Re: Help with IF Noise, DSP Noise, NR settings

David Woolley (E.L)
In reply to this post by Bob McGraw - K4TAX
The below statement surprised me.  That is not how noise blanking
normally works; normally it will suppress  any wide band pulse.  The
typical arrangement uses a high bandwidth, low delay, path, to detect
the pulse.  It can then mute the signal path by the time the pulse gets
through the narrower filters on the main path.  That will happen with
single, or randomly spaced spikes.

--
David Woolley
K2 06123

On 13/06/2019 14:09, Bob McGraw K4TAX wrote:
> The Noise Blanker only affects repetitive pulse noise such as ignition
> type noise.  Lightning and atmospheric is random noise.


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Re: Help with IF Noise, DSP Noise, NR settings

Brian Hunt
In reply to this post by KC6CNN

For weak CW signals try NR= mF5-3 with IF BW= 700-1000 Hz and APF on.  The mF#-# settings mix unprocessed signal with the NR processed results. the second # sets how much.  The wider IF bandwidth lets the NR work optimally on random, uncorrelated noise while the APF pops the desired signal out of the muddle the NR makes.  Tune carefully using the FINE tuning rate, the APF is very narrow.  There can be no other stronger signals in the IF passband.
 
I haven't had much success using the DSP NB.  The IF NB works well on pulse noise and some powerline noise but if there is a very strong signal nearby it will create some nasty artifacts.
 
73,
Brian, K0DTJ
 
 
KC6CNN wrote .....
Is there any information or help in finding a good setting for these.



 
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Re: Help with IF Noise, DSP Noise, NR settings

Wes Stewart-2
In reply to this post by Bob McGraw - K4TAX
  I have one little nit to pick with this.  In a properly designed blanker,
there is no requirement that the noise be repetitive; blanking should occur on a
single pulse or on random pulses.  Blanking becomes ineffective when 1) an
undesired signal appears in the detection bandwidth that exceeds the threshold
and triggers the blanker more or less continuously or 2) the duration of the
noise pulse is so long that intelligibility suffers. Atmospherics fall into this
latter category.

See: http://k6mhe.com/n7ws/Noise_Blanker.pdf  for more of my opinion on this. 
(The missing text in the last paragraph was not my fault.)

Actually now that I think about it, I have another nit.  Although the control on
the K3 front panel says "RF Gain", which I guess differentiates it from AF Gain,
it really should say "IF Gain".  It has absolutely nothing to do with affecting
the gain ahead of the i-f amplifier.  Front end attenuation can affect noise
power into preamp and/or the first mixer (and noise blanker circuit); "RF Gain"
cannot.  In fact RF Gain is applied first to exactly the same point as AGC, the
post-filter FET.  The FET can't tell the difference, which might be news to the
guys who turn off the AGC and "ride the RF gain control."

Wes  N7WS

On 6/13/2019 6:09 AM, Bob McGraw K4TAX wrote:

> The Noise Blanker only affects repetitive pulse noise such as ignition type
> noise.  Lightning and atmospheric is random noise. As to the Noise Reduction,
> I find that use of the Attenuation and RF Gain control is far superior to
> using DSP systems.  Also remember it is Noise Reduction and not noise
> elimination as many seem would like to believe.  If one realized 6 dB of noise
> reduction using the system that's good.   At the same time, any noise
> reduction system will add distortion to a SSB or CW signal.
>
> From very authoritative source, the optimum receiver performance configuration
> is to have the no signal band noise about 10 dB above the noise floor of the
> receiver.    Since we can't change the noise floor of the receiver, the option
> is to change the incoming level of the noise as presented to the receiver
> input. The K3S receiver noise floor is about -135 dBM.   If one has a no
> signal band noise of S-5 or -97 dBm, the difference is 38 dB. This says we
> need 28 dB of Attenuation and RF Gain reduction.    That would be 15 dB of
> Attenuation and about 2 S units of RF Gain reduction or 10 dB of Attenuation
> and about 3 S units of RF Gain reduction.     This in no way changes the
> sensitivity of  the receiver nor does it impede the ability to hear weak
> signals. Unfortunately many hams belie that more gain is needed to hear weak
> signals.   With receivers of 50+ years ago often the receiver noise exceeded
> the band noise.  That however is not true with today's modern receivers.
>
> As to using the Noise Reduction,  I do not use it at all for SSB and for CW.  
> If  I do use it I find  F1 and a value of 1 to 3 about all I'm willing to
> accept.  Of course the type and magnitude of the noise does require different
> settings.
>
> If I use the Noise Blanker I find it necessary to first set the IF NB to OFF. 
> Then adjust the DSP through its values to get what seems to be the best
> result.  Remember the value.  Then set the DSP NB to OFF.   Then to the IF
> noise adjustment and find what seems to be the best result.   Leave it at that
> and then back to the DSP Noise blanker and set it to the previous obtained
> value.    This optimized them individually.   I've not been successful in
> trying to adjust both at the same time.    And remember it only works on
> repetitive noise such as ignition noise or line noise and not random
> atmospheric noise.
>
> The receiver gain method works best.   Hope this helps.
>
> 73
>
> Bob, K4TAX
>
>
>
> On 6/13/2019 6:43 AM, Nr4c wrote:
>> This is not an easy thing.
>>
>> First, are you hearing general band noise, a constant “ shhhhhhhhhhhh” or
>> pulses as in lightning, power line, or ignition type noise.
>>
>> For band noise, the NR will be your best solution. Experiment, but don’t go
>> too deep. Deep settings will distort and make it sound like you’re underwater.
>>
>> For the pulse noises, try IF first, again don’t use extreme settings. If this
>> doesn’t work, try the DSP settings and see if this will work.
>>
>> I have NB set to Med4. NR is set to F1-3.
>>
>> YMMV.
>>
>> Have fun!
>>
>> Sent from my iPhone
>> ...nr4c. bill
>>
>>
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]


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Re: Help with IF Noise, DSP Noise, NR settings

Don Wilhelm
It may be better said that a Noise Blanker responds best to impulses
with a fast rise time like ignition noise from a gasoline engine.  It
does not have to be repetitive (but often is).

73,
Don W3FPR

On 6/14/2019 2:05 PM, Wes wrote:

>   I have one little nit to pick with this.  In a properly designed
> blanker, there is no requirement that the noise be repetitive; blanking
> should occur on a single pulse or on random pulses.  Blanking becomes
> ineffective when 1) an undesired signal appears in the detection
> bandwidth that exceeds the threshold and triggers the blanker more or
> less continuously or 2) the duration of the noise pulse is so long that
> intelligibility suffers. Atmospherics fall into this latter category.
>
> See: http://k6mhe.com/n7ws/Noise_Blanker.pdf  for more of my opinion on
> this. (The missing text in the last paragraph was not my fault.)
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Re: Help with IF Noise, DSP Noise, NR settings

Bob McGraw - K4TAX
In reply to this post by David Woolley (E.L)
David et al;

My statement is almost word for word from the Elecraft K3 manual.   And
some from work done by Art Collins and company at Collins Radio.  They
prescribed the function of a Noise Blanker as follows:

"The following operational requirements were kept in mind:

 1. Reduction of ignition noise from vehicles.
 2. Reduction of power line corona noise occurring at 120 CPS repetition
    rates.
 3. Reduction of local thunderstorm disturbances.
 4. And, in general, reduction of any man-made noise which is impulsive
    in nature.

Basically, all the above forms of noise interference are impulsive
functions with repetition rates than can extend up to 100 KC in the case
of the strokes in a thunderstorm."

Those are my sources.

Again both descriptions use repetitive pulse rates which are impulsive
in nature.    In order for a NB to function efficiently it is best
suited in a wide band signal path that is not restricted by filters.  
Hence a wide IF stage of the receiver before any filtering.

As to thunderstorms, since lightning contains many pulses in a single
stroke, the NB is suited to minimize those pulses while at the same
time, the bulk of the strike energy is affecting the receiver in other
means. Namely AGC.  Many receivers suffer grossly from this phenomenon.
   Fortunately Elecraft and Tentec took actions with their designs to
minimize this phenomenon based  on the work of Rob Sherwood.    And
regarding thunderstorms, there is a clear difference in the stroke and
content of such for  a "local thunderstorm" as compared to the noise
from distant thunderstorms several hundred miles away.   The distant
thunderstorm is affected by propagation and may have several wave fronts
with different arrival times where as a local thunderstorm only has a
single wave front.   Hence the waveform is quite different and the means
to suppress such will be different.


73

Bob, K4TAX


On 6/14/2019 12:24 PM, David Woolley wrote:
> The below statement surprised me.  That is not how noise blanking
> normally works; normally it will suppress  any wide band pulse. The
> typical arrangement uses a high bandwidth, low delay, path, to detect
> the pulse.  It can then mute the signal path by the time the pulse
> gets through the narrower filters on the main path. That will happen
> with single, or randomly spaced spikes.
>
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Re: Help with IF Noise, DSP Noise, NR settings

Wes Stewart-2
Thanks for the mention of the Collins document.  I had not seen it and after a
search and finding it, I was amazed at how much of it was similar to what I
established independently.

If you happen to look at the bottom of my QRZ bio you can see the mobile rig
belonging to a boyhood neighbor.  He gave me my first exams, but I wouldn't call
him an Elmer in the mentoring sense.  He built the mobile because a powerline
running through his property prevented him from hearing anything.  That was
until Collins came out with their noise blanker for his 75A-4. (I never
understood why he didn't just move but I think his trust fund income came after
he moved there.)

Wes  N7WS


On 6/14/2019 11:33 AM, Bob McGraw K4TAX wrote:

> David et al;
>
> My statement is almost word for word from the Elecraft K3 manual.   And some
> from work done by Art Collins and company at Collins Radio.  They prescribed
> the function of a Noise Blanker as follows:
>
> "The following operational requirements were kept in mind:
>
> 1. Reduction of ignition noise from vehicles.
> 2. Reduction of power line corona noise occurring at 120 CPS repetition
>    rates.
> 3. Reduction of local thunderstorm disturbances.
> 4. And, in general, reduction of any man-made noise which is impulsive
>    in nature.
>
> Basically, all the above forms of noise interference are impulsive functions
> with repetition rates than can extend up to 100 KC in the case of the strokes
> in a thunderstorm."
>
> Those are my sources.
>
> Again both descriptions use repetitive pulse rates which are impulsive in
> nature.    In order for a NB to function efficiently it is best suited in a
> wide band signal path that is not restricted by filters.   Hence a wide IF
> stage of the receiver before any filtering.
>
> As to thunderstorms, since lightning contains many pulses in a single stroke,
> the NB is suited to minimize those pulses while at the same time, the bulk of
> the strike energy is affecting the receiver in other means. Namely AGC.  Many
> receivers suffer grossly from this phenomenon.   Fortunately Elecraft and
> Tentec took actions with their designs to minimize this phenomenon based on
> the work of Rob Sherwood.    And regarding thunderstorms, there is a clear
> difference in the stroke and content of such for  a "local thunderstorm" as
> compared to the noise from distant thunderstorms several hundred miles away.  
> The distant thunderstorm is affected by propagation and may have several wave
> fronts with different arrival times where as a local thunderstorm only has a
> single wave front.   Hence the waveform is quite different and the means to
> suppress such will be different.
>
>
> 73
>
> Bob, K4TAX

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Re: Help with IF Noise, DSP Noise, NR settings

k6dgw
In reply to this post by Bob McGraw - K4TAX
I have never found a noise blanker to be of particular value, if any at
all, on general power line hash [the "grass" along the baseline of a
panadapter.  At our prior home in Auburn CA, I had a 3-phase ~70 KV
transmission line on  running across the lower end of the property that
connected a series of hydroelectric plants above and below us, and two
3-phase 112 KV transmission lines on towers about 1/4 mile away.  The 70
KV line was essentially quiet.  The 112 KV lines was perhaps S3-4 on 80
and had a fairly high frequency sound ... I guess from the 3-separate
phases with peaks occuring at 360 Hz.  The K3 NB was ineffective against
it.  With the level set high enough to affect the noise level in the
headphones, SSB was highly distorted and CW was chopped up.

Here in NV, we are about 1/2 mile from a 500 KV 3-phase transmission
line connecting a power plant in Patrick NV to someplace up in OR,
probably along the Columbia.  It is fairly quiet, S2-3 on 80, and again
seems to be high frequency enough that the K3 NB is ineffective.  I've
concluded that, while technically it all is impulsive [arcs on voltage
peaks], the peaks must overlap enough and/or are of a high enough
frequency that the NB either can't find them or punches too many too big
holes in the signal.  It might be more effective on noise from a single
phase line, don't know.

I rarely hear ignition noise from spark plugs anymore, however the
landscape maintenance crew showed up earlier this spring to aerate and
de-thatch the grass.  Their aerator gizmo had an old 7 HP engine with
strong ignition noise.  The NB took all of it out just fine at very low
settings.

73,
Fred ["Skip"] K6DGW
Sparks NV DM09dn
Washoe County

On 6/14/2019 11:33 AM, Bob McGraw K4TAX wrote:

> David et al;
>
> My statement is almost word for word from the Elecraft K3 manual.  
> And some from work done by Art Collins and company at Collins Radio. 
> They prescribed the function of a Noise Blanker as follows:
>
> "The following operational requirements were kept in mind:
>
> 1. Reduction of ignition noise from vehicles.
> 2. Reduction of power line corona noise occurring at 120 CPS repetition
>    rates.
> 3. Reduction of local thunderstorm disturbances.
> 4. And, in general, reduction of any man-made noise which is impulsive
>    in nature.
>
> Basically, all the above forms of noise interference are impulsive
> functions with repetition rates than can extend up to 100 KC in the
> case of the strokes in a thunderstorm."
>
> Those are my sources.
>
> Again both descriptions use repetitive pulse rates which are impulsive
> in nature.    In order for a NB to function efficiently it is best
> suited in a wide band signal path that is not restricted by filters.  
> Hence a wide IF stage of the receiver before any filtering.
>
> As to thunderstorms, since lightning contains many pulses in a single
> stroke, the NB is suited to minimize those pulses while at the same
> time, the bulk of the strike energy is affecting the receiver in other
> means. Namely AGC.  Many receivers suffer grossly from this
> phenomenon.   Fortunately Elecraft and Tentec took actions with their
> designs to minimize this phenomenon based on the work of Rob
> Sherwood.    And regarding thunderstorms, there is a clear difference
> in the stroke and content of such for  a "local thunderstorm" as
> compared to the noise from distant thunderstorms several hundred miles
> away.   The distant thunderstorm is affected by propagation and may
> have several wave fronts with different arrival times where as a local
> thunderstorm only has a single wave front.   Hence the waveform is
> quite different and the means to suppress such will be different.
>
>
> 73
>
> Bob, K4TAX

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Re: Help with IF Noise, DSP Noise, NR settings

W2xj
Looking at the MECC map, I’m pretty sure the 500 KV line is +- 500 KV DC so that would by itself make it pretty quiet.

Sent from my iPad

> On Jun 15, 2019, at 7:34 PM, Fred Jensen <[hidden email]> wrote:
>
> I have never found a noise blanker to be of particular value, if any at all, on general power line hash [the "grass" along the baseline of a panadapter.  At our prior home in Auburn CA, I had a 3-phase ~70 KV transmission line on  running across the lower end of the property that connected a series of hydroelectric plants above and below us, and two 3-phase 112 KV transmission lines on towers about 1/4 mile away.  The 70 KV line was essentially quiet.  The 112 KV lines was perhaps S3-4 on 80 and had a fairly high frequency sound ... I guess from the 3-separate phases with peaks occuring at 360 Hz.  The K3 NB was ineffective against it.  With the level set high enough to affect the noise level in the headphones, SSB was highly distorted and CW was chopped up.
>
> Here in NV, we are about 1/2 mile from a 500 KV 3-phase transmission line connecting a power plant in Patrick NV to someplace up in OR, probably along the Columbia.  It is fairly quiet, S2-3 on 80, and again seems to be high frequency enough that the K3 NB is ineffective.  I've concluded that, while technically it all is impulsive [arcs on voltage peaks], the peaks must overlap enough and/or are of a high enough frequency that the NB either can't find them or punches too many too big holes in the signal.  It might be more effective on noise from a single phase line, don't know.
>
> I rarely hear ignition noise from spark plugs anymore, however the landscape maintenance crew showed up earlier this spring to aerate and de-thatch the grass.  Their aerator gizmo had an old 7 HP engine with strong ignition noise.  The NB took all of it out just fine at very low settings.
>
> 73,
> Fred ["Skip"] K6DGW
> Sparks NV DM09dn
> Washoe County
>
>> On 6/14/2019 11:33 AM, Bob McGraw K4TAX wrote:
>> David et al;
>>
>> My statement is almost word for word from the Elecraft K3 manual.   And some from work done by Art Collins and company at Collins Radio.  They prescribed the function of a Noise Blanker as follows:
>>
>> "The following operational requirements were kept in mind:
>>
>> 1. Reduction of ignition noise from vehicles.
>> 2. Reduction of power line corona noise occurring at 120 CPS repetition
>>    rates.
>> 3. Reduction of local thunderstorm disturbances.
>> 4. And, in genera

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Re: Help with IF Noise, DSP Noise, NR settings

Bill-3
In reply to this post by k6dgw
When it comes to eliminating extraneous noise, I have always found the
K3 to be very lacking of any super powers.

Mostly, the results were about the same as any other rig out there. Kind
of OK for ignition noise - using the NB. Of course the NB can screw with
the bandwidth of the receiver and allow nearby signals to interfere when
they would normally not. Nothing new about this - just like all the
others. So far as the NR - all the various (and there are many) settings
result in lowered audio output and various levels of "under water"
effects. Effectiveness against lightning static is nonexistent.

I would be remiss if I did not mention that my IC-7300's NR is very
effective against junk when needed and does not introduce "under water"
effects. It is also quite effective against lightning static - not 100%,
however, I would estimate 80 to 90%. As a result, the 7300 is the go-to
rig for noisy weather conditions. I have had no occasion to try the NB,
so cannot report on same.

As always, the ATT and/or RF GAIN are your friends.






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Re: Help with IF Noise, DSP Noise, NR settings

W2xj
In reply to this post by W2xj
That’s the one. The problem is the WECC map does not have many geographic references. Just distribution stations and converter stations. The other line you referenced is 345 KV according to the WECC map. It Sierra Pacific power.

Sent from my iPhone

> On Jun 16, 2019, at 13:58, Fred Jensen <[hidden email]> wrote:
>
> Ummm ... actually no.  The line next to us is 2 3-phase AC circuits, based on the size of the insulators, one is 500 KV and the other is 230 KV.  Both are definitely AC, I've seen the transformers they both come from at the power plant at Patrick NV.  Each conductor consists of two parallel strands and there is a lot of anti-corona hardware on the insulators which may account for why it is relatively quiet.  The K3 NB is essentially ineffective against its noise, which is quite obvious on the P3.
>
> I believe you are referring to "Path 65," aka the "Pacific DC Intertie."  In the south, it terminates at a large switching/converter station in Sylmar CA north of Los Angeles right next to I-5.  It runs north through the Owens Valley [adjacent to and often crossing US 395] and terminates in a switching/converter station near The Dalles, OR.  It's primary purpose is to carry plentiful [and cheap] electricity from the Columbia River south to Southern CA.  It crosses I-80 near Fernley NV, 20 or so minutes east of us.  It is distinctive because it has only two conductors and, except for the dead-ends at direction changes, is generally on very simple pylon towers.  I attached a photo from Wikipedia which may or may not come thru.
>
> Path 65 is very quiet, essentially no change in noise when driving under it.  I believe it normally operates at +/-500 KV, but can also be operated against ground at between 700 KV and 1 MV.  The earth electrode for the Sylmar converter station is submerged in the Pacific Ocean west of the station.  It's not quite pure DC, there's a 12-phase 720 cycle ripple on it from the rectifiers.
>
> 73,
> Fred ["Skip"] K6DGW
> Sparks NV DM09dn
> Washoe County
>
>> On 6/15/2019 10:55 PM, W2xj wrote:
>> Looking at the MECC map, I’m pretty sure the 500 KV line is +- 500 KV DC so that would by itself make it pretty quiet.
>>
>> Sent from my iPad
>>
>
> <Tower.jpg>
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Re: Help with IF Noise, DSP Noise, NR settings

Bill K9YEQ
In reply to this post by Bill-3
Using the AGC control is also a big factor when dealing with noise with the K3/S.  I find the controls help me with communications as the noise sources where I live are many.  Understanding the use of the controls as written by Don W3FPR, is very helpful.  He has a website that has much educational and instructional ways to use the controls effectively.

73,
Bill
K9YEQ

https://wrj-tech.com/

-----Original Message-----
From: [hidden email] <[hidden email]> On Behalf Of Bill
Sent: Sunday, June 16, 2019 9:04 AM
To: [hidden email]
Subject: Re: [Elecraft] Help with IF Noise, DSP Noise, NR settings

When it comes to eliminating extraneous noise, I have always found the
K3 to be very lacking of any super powers.

Mostly, the results were about the same as any other rig out there. Kind of OK for ignition noise - using the NB. Of course the NB can screw with the bandwidth of the receiver and allow nearby signals to interfere when they would normally not. Nothing new about this - just like all the others. So far as the NR - all the various (and there are many) settings result in lowered audio output and various levels of "under water"
effects. Effectiveness against lightning static is nonexistent.

I would be remiss if I did not mention that my IC-7300's NR is very effective against junk when needed and does not introduce "under water"
effects. It is also quite effective against lightning static - not 100%, however, I would estimate 80 to 90%. As a result, the 7300 is the go-to rig for noisy weather conditions. I have had no occasion to try the NB, so cannot report on same.

As always, the ATT and/or RF GAIN are your friends.






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