Re: [Elecraft] Noise Blankers

[Wes Stewart]

In addition to the hard limiter Elecraft provided threshold and slope controls 
in the AGC system.



On 9/3/2017 4:04 PM, Ron D'Eau Claire wrote:

The advantage of controlling the gain manually is not an "old wife's tale". 
Rather, it's clearly just a technique that is not for everyone.

AGC will reduce the gain according to the strongest signal inside the I.F. passband. 
Manually riding the "RF" gain ensures that a very weak signal is not affected 
by a strong signal that is also inside the I.F. passband. Of course that means your ears 
could be blasted by that strong signal, which is why Wayne included a hard limiter that 
can be enabled to chop such a signal down to size, making it no louder than the weak 
signal we want to copy.



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Re: [Elecraft] Noise Blankers

[Fred Moore]

Ron, you are 100% on the money.. I was thinking about how I wanted to
explain the same thing.. thanks.. Fred

Fred Moore
email: f...@fmeco.com
   wd8...@gmail.com
phone: 321-217-8699

On 9/3/17 7:04 PM, Ron D'Eau Claire wrote:
> The advantage of controlling the gain manually is not an "old wife's tale". 
> Rather, it's clearly just a technique that is not for everyone. 
>
> AGC will reduce the gain according to the strongest signal inside the I.F. 
> passband. Manually riding the "RF" gain ensures that a very weak signal is 
> not affected by a strong signal that is also inside the I.F. passband. Of 
> course that means your ears could be blasted by that strong signal, which is 
> why Wayne included a hard limiter that can be enabled to chop such a signal 
> down to size, making it no louder than the weak signal we want to copy. 
>
> It has become a moot point for many operators today who cannot read CW if 
> they are hearing two or three (or more) signals within the I.F. passband all 
> at the same time. For them, it's essential to have enough I.F. selectivity to 
> isolate one signal and so AGC is just fine. 
>
> But some of us have a lifetime of experience sorting out multiple signals 
> with our gray matter between the ears and prefer to continue to do so -- 
> probably until we all become SKs. 
>
> 73, Ron AC7AC
>
>  
>
> -Original Message-
> From: elecraft-boun...@mailman.qth.net 
> [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Wes Stewart
> Sent: Sunday, September 3, 2017 3:00 PM
> To: elecraft@mailman.qth.net
> Subject: Re: [Elecraft] Noise Blankers
>
> Just a couple of points.
>
> In the K3(S) there is no "RF Gain" control unless by RF gain you mean "It's 
> not the audio gain gain control."
>
> The "RF" gain control operates on the i-f amplifier, which is after the 
> analog noise blanker. In this regard, it is little different from AGC, which 
> operates on exactly the same circuitry. Why some people believe that they are 
> better at controlling i-f gain than the AGC system does is beyond me, but old 
> wife's tales die hard.  If this is hard to fathom, watch the S meter as you 
> reduce "RF" 
> gain.  The reading increases, no different from letting the AGC do it.
>
> Attenuation is a different matter. It operates at RF and is a viable tool.
>
> About noise blanking, I think I had a little to say about that almost 40 years
> ago: http://k6mhe.com/n7ws/Noise_Blanker.pdf
>
> Wes  N7WS
>
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Re: [Elecraft] Noise Blankers

[Ron D'Eau Claire]

The advantage of controlling the gain manually is not an "old wife's tale". 
Rather, it's clearly just a technique that is not for everyone. 

AGC will reduce the gain according to the strongest signal inside the I.F. 
passband. Manually riding the "RF" gain ensures that a very weak signal is not 
affected by a strong signal that is also inside the I.F. passband. Of course 
that means your ears could be blasted by that strong signal, which is why Wayne 
included a hard limiter that can be enabled to chop such a signal down to size, 
making it no louder than the weak signal we want to copy. 

It has become a moot point for many operators today who cannot read CW if they 
are hearing two or three (or more) signals within the I.F. passband all at the 
same time. For them, it's essential to have enough I.F. selectivity to isolate 
one signal and so AGC is just fine. 

But some of us have a lifetime of experience sorting out multiple signals with 
our gray matter between the ears and prefer to continue to do so -- probably 
until we all become SKs. 

73, Ron AC7AC

 

-Original Message-
From: elecraft-boun...@mailman.qth.net 
[mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Wes Stewart
Sent: Sunday, September 3, 2017 3:00 PM
To: elecraft@mailman.qth.net
Subject: Re: [Elecraft] Noise Blankers

Just a couple of points.

In the K3(S) there is no "RF Gain" control unless by RF gain you mean "It's not 
the audio gain gain control."

The "RF" gain control operates on the i-f amplifier, which is after the analog 
noise blanker. In this regard, it is little different from AGC, which operates 
on exactly the same circuitry. Why some people believe that they are better at 
controlling i-f gain than the AGC system does is beyond me, but old wife's 
tales die hard.  If this is hard to fathom, watch the S meter as you reduce 
"RF" 
gain.  The reading increases, no different from letting the AGC do it.

Attenuation is a different matter. It operates at RF and is a viable tool.

About noise blanking, I think I had a little to say about that almost 40 years
ago: http://k6mhe.com/n7ws/Noise_Blanker.pdf

Wes  N7WS

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Re: [Elecraft] Noise Blankers

[Richard Lamont]

On 03/09/17 20:38, Wes Stewart wrote:

> The K3S blanker is slightly better than
> useless. When I set it aggressive enough to be audibly useful, FT8
> decodes multiple signals at 120 Hz intervals, which upsets sequencing.

That's an inevitable consequence of how a noise blanker works.

It removes power line noise by muting reception 120 (or 100) times a
second, corresponding to peaks in the power line voltage when the arcing
occurs.

If you chop an audio tone up at 120 Hz, you are amplitude modulating the
tone with a 120 Hz waveform. That produces sidebands either side of the
tone 'carrier'. This is why you should never use a noise blanker with
FT8 and similar modes.

The best way to use a rig with WSJT-X is, generally speaking, to make
the computer do as much as possible and make the rig do as little as
possible. Treat it more or less as a dumb transverter. Don't use the
noise blanker, don't reduce the bandwidth below about 2.5 kHz, don't use
the notch filter. WSJT-X's decoder works best if you just get the level
about right and let it deal with the QRM.

73,
Richard G4DYA
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Re: [Elecraft] Noise Blankers

[Wes Stewart]

Just a couple of points.

In the K3(S) there is no "RF Gain" control unless by RF gain you mean "It's not 
the audio gain gain control."


The "RF" gain control operates on the i-f amplifier, which is after the analog 
noise blanker. In this regard, it is little different from AGC, which operates 
on exactly the same circuitry. Why some people believe that they are better at 
controlling i-f gain than the AGC system does is beyond me, but old wife's tales 
die hard.  If this is hard to fathom, watch the S meter as you reduce "RF" 
gain.  The reading increases, no different from letting the AGC do it.


Attenuation is a different matter. It operates at RF and is a viable tool.

About noise blanking, I think I had a little to say about that almost 40 years 
ago: http://k6mhe.com/n7ws/Noise_Blanker.pdf


Wes  N7WS



On 9/3/2017 1:48 PM, Bob McGraw K4TAX wrote:
Depending the type of noise, for repetitive pulse type noise only,  the Noise 
Blanker does it job.  Now one must understand that all pulse noise is not 
alike.  Therefore, different values of NB, both with the  IF values and with 
DSP values, will require some adjustments.    If the noise is not repetitive 
then the NB is not the better choice but the NR is the better choice.  Again, 
depending on they type of noise, certain combinations of NR values will be 
necessary.


Yes, that is correct in that the Noise Reduction function is not available or 
can not be activated in the DATA mode.  However the Noise Blanker can be used 
in the DATA mode.   Again, the Noise Blanker is for repetitive pulse type noise.


I've spoken with many hams and find their understanding of Noise Reduction  
being described as often does not work as expected. Further discussion seems 
to indicate they want NENoise Elimination.    Well, NRNoise 
Reduction does in fact work when the values are selected based on the type of 
broad noise spectrum being encountered.  NR has very little effect on pulse 
type noise.


One fact not clearly understood, is that most hams operate with too much RF 
Gain.   Thus the correct application of ATTENUATION and RF Gain reduction will 
greatly improve receiver performance in the face of noise.


Optimizing receiver gain compared to band noise and the noise floor of the 
receiver is explained in a quote from Rob Sherwood, Sherwood Engineering:


"If receiver noise floor is 10 dB below band noise, the receiver is 
contributing less than 0.5 dB of the total noise.
Band noise varies by band over 30 dB, 160-10 meters. It also varies by 
direction and time of day, plus what the sun is doing. In an noisy urban 
environment it is anybody's guess as to your band noise level.
A simple test is to see how much the noise coming out your speaker increases 
when you switch between a dummy load and your antenna, when tuned to a dead 
spot on the band.
Example on 10 meters at my rural QTH, IC-756 Pro III: preamp OFF, noise goes 
up 3 dB. That means the receiver is contributing half the noise. Preamp 1 ON, 
band noise goes up 9.5 dB.   Almost all legacy receivers are designed for 10 
meters, and attenuation is desirable on the low HF bands."


In Rob's first statement, how do we get the band noise to be 10 dB above 
receiver noise?  Use Attenuation and RF  Gain reduction. As an example, if 
receiver noise floor is -130 dBm and the band noise, no signal, is S-5 or -97 
dBm, the difference being 33 dB. This would then indicate one should employ 15 
dB of Attenuation and 8 dB of RF Gain reduction.  Or 10 dB of Attenuation and 
some 13 dB of RF Gain reduction.   Of course the band noise will be comprised 
of different noise components, depending on band and many other factors as he 
suggests.


73

Bob, K4TAX


On 9/3/2017 3:06 PM, Keith Onishi wrote:

In my experience, NR is much better than NB against power line noise.
However, NR does not work on DATA mode. I use BHI Compact In-line DSP Noise 
Eliminating Module, which is inserted between K3 line out and USB audio module.


For effectively eliminating noise, tuning RF gain and AGC level in addition 
to NB and/or NR would give you better results.


de JH3SIF, Keith



2017/09/04 4:38、Wes Stewart  のメール：

I agree. The adjustments are far too many and arcane.  I'm currently plagued 
with powerline noise that has yet to be fixed, although they are supposed to 
be working on it. The K3S blanker is slightly better than useless. When I 
set it aggressive enough to be audibly useful, FT8 decodes multiple signals 
at 120 Hz intervals, which upsets sequencing.


I'm finding that my SDR-IQ that I normally use only as a bandscope, has 
better noise blanking on its demodulated audio than the K3.  Too bad I can't 
use it with WSJT-X.


I suspect, but do not know for sure, (maybe the designer can enlighten us) 
that there is insufficient delay in the (analog) signal path and the noise 
gets through before blanking takes place.


Wes  N7WS

Re: [Elecraft] Noise Blankers

[Bob McGraw K4TAX]

Depending the type of noise, for repetitive pulse type noise only,  the 
Noise Blanker does it job.  Now one must understand that all pulse noise 
is not alike.  Therefore, different values of NB, both with the  IF 
values and with DSP values, will require some adjustments.    If the 
noise is not repetitive then the NB is not the better choice but the NR 
is the better choice.  Again, depending on they type of noise, certain 
combinations of NR values will be necessary.


Yes, that is correct in that the Noise Reduction function is not 
available or can not be activated in the DATA mode.  However the Noise 
Blanker can be used in the DATA mode.   Again, the Noise Blanker is for 
repetitive pulse type noise.


I've spoken with many hams and find their understanding of Noise 
Reduction  being described as often does not work as expected. Further 
discussion seems to indicate they want NENoise Elimination.    
Well, NRNoise Reduction does in fact work when the values are 
selected based on the type of broad noise spectrum being encountered.  
NR has very little effect on pulse type noise.


One fact not clearly understood, is that most hams operate with too much 
RF Gain.   Thus the correct application of ATTENUATION and RF Gain 
reduction will greatly improve receiver performance in the face of noise.


Optimizing receiver gain compared to band noise and the noise floor of 
the receiver is explained in a quote from Rob Sherwood, Sherwood 
Engineering:


"If receiver noise floor is 10 dB below band noise, the receiver is 
contributing less than 0.5 dB of the total noise.
Band noise varies by band over 30 dB, 160-10 meters. It also varies by 
direction and time of day, plus what the sun is doing. In an noisy urban 
environment it is anybody's guess as to your band noise level.
A simple test is to see how much the noise coming out your speaker 
increases when you switch between a dummy load and your antenna, when 
tuned to a dead spot on the band.
Example on 10 meters at my rural QTH, IC-756 Pro III: preamp OFF, noise 
goes up 3 dB. That means the receiver is contributing half the noise. 
Preamp 1 ON, band noise goes up 9.5 dB.   Almost all legacy receivers 
are designed for 10 meters, and attenuation is desirable on the low HF 
bands."


In Rob's first statement, how do we get the band noise to be 10 dB above 
receiver noise?  Use Attenuation and RF  Gain reduction. As an example, 
if receiver noise floor is -130 dBm and the band noise, no signal, is 
S-5 or -97 dBm, the difference being 33 dB. This would then indicate one 
should employ 15 dB of Attenuation and 8 dB of RF Gain reduction.  Or 10 
dB of Attenuation and some 13 dB of RF Gain reduction.   Of course the 
band noise will be comprised of different noise components, depending on 
band and many other factors as he suggests.


73

Bob, K4TAX


On 9/3/2017 3:06 PM, Keith Onishi wrote:

In my experience, NR is much better than NB against power line noise.
However, NR does not work on DATA mode. I use BHI Compact In-line DSP Noise 
Eliminating Module, which is inserted between K3 line out and USB audio module.

For effectively eliminating noise, tuning RF gain and AGC level in addition to 
NB and/or NR would give you better results.

de JH3SIF, Keith



2017/09/04 4:38、Wes Stewart  のメール：

I agree. The adjustments are far too many and arcane.  I'm currently plagued 
with powerline noise that has yet to be fixed, although they are supposed to be 
working on it. The K3S blanker is slightly better than useless. When I set it 
aggressive enough to be audibly useful, FT8 decodes multiple signals at 120 Hz 
intervals, which upsets sequencing.

I'm finding that my SDR-IQ that I normally use only as a bandscope, has better 
noise blanking on its demodulated audio than the K3.  Too bad I can't use it 
with WSJT-X.

I suspect, but do not know for sure, (maybe the designer can enlighten us) that 
there is insufficient delay in the (analog) signal path and the noise gets 
through before blanking takes place.

Wes  N7WS



On 9/3/2017 9:18 AM, K9MA wrote:

I have never found the K3 noise blanker to be effective.  On the other hand, in 
side-by-side comparisons, the noise blanker in my old FT-1000D can be very 
effective on my ever present power line noise.  However, like all noise 
blankers of that design, it only works if there are no strong signals within 
many kHz of the operating frequency, so it's completely useless on a crowded 
band.  The only way around this I know of is to use a second receiver, tuned to 
a clear spot nearby, to control the noise blanker.

BTW, the K3 noise blanker uses a filter with a bandwidth of about 100 kHz.  The 
idea is that, in such a wide bandwidth, the amplitude of the noise pulses 
should be large, making them easier to distinguish from signals.  (The FT-1000 
uses something like 15 kHz.)  However, I've never been able to get the K3 NB to 
work, even on a completely dead band.  Under the same 

Re: [Elecraft] Noise Blankers

[Keith Onishi]

In my experience, NR is much better than NB against power line noise. 
However, NR does not work on DATA mode. I use BHI Compact In-line DSP Noise 
Eliminating Module, which is inserted between K3 line out and USB audio module.

For effectively eliminating noise, tuning RF gain and AGC level in addition to 
NB and/or NR would give you better results.

de JH3SIF, Keith


> 2017/09/04 4:38、Wes Stewart  のメール：
> 
> I agree. The adjustments are far too many and arcane.  I'm currently plagued 
> with powerline noise that has yet to be fixed, although they are supposed to 
> be working on it. The K3S blanker is slightly better than useless. When I set 
> it aggressive enough to be audibly useful, FT8 decodes multiple signals at 
> 120 Hz intervals, which upsets sequencing.
> 
> I'm finding that my SDR-IQ that I normally use only as a bandscope, has 
> better noise blanking on its demodulated audio than the K3.  Too bad I can't 
> use it with WSJT-X.
> 
> I suspect, but do not know for sure, (maybe the designer can enlighten us) 
> that there is insufficient delay in the (analog) signal path and the noise 
> gets through before blanking takes place.
> 
> Wes  N7WS
> 
> 
> 
> On 9/3/2017 9:18 AM, K9MA wrote:
>> I have never found the K3 noise blanker to be effective.  On the other hand, 
>> in side-by-side comparisons, the noise blanker in my old FT-1000D can be 
>> very effective on my ever present power line noise.  However, like all noise 
>> blankers of that design, it only works if there are no strong signals within 
>> many kHz of the operating frequency, so it's completely useless on a crowded 
>> band.  The only way around this I know of is to use a second receiver, tuned 
>> to a clear spot nearby, to control the noise blanker.
>> 
>> BTW, the K3 noise blanker uses a filter with a bandwidth of about 100 kHz.  
>> The idea is that, in such a wide bandwidth, the amplitude of the noise 
>> pulses should be large, making them easier to distinguish from signals.  
>> (The FT-1000 uses something like 15 kHz.)  However, I've never been able to 
>> get the K3 NB to work, even on a completely dead band.  Under the same 
>> conditions, I can often get a 20 dB reduction with the other radio.  That I 
>> don't understand.  I should investigate that sometime.
>> 
>> 73,
>> 
>> Scott K9MA
>> 
>> --
>> 
>> Scott Ellington
>> 
>>  
> 
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Re: [Elecraft] Noise Blankers

[Wes Stewart]

I agree. The adjustments are far too many and arcane.  I'm currently plagued 
with powerline noise that has yet to be fixed, although they are supposed to be 
working on it. The K3S blanker is slightly better than useless. When I set it 
aggressive enough to be audibly useful, FT8 decodes multiple signals at 120 Hz 
intervals, which upsets sequencing.


I'm finding that my SDR-IQ that I normally use only as a bandscope, has better 
noise blanking on its demodulated audio than the K3.  Too bad I can't use it 
with WSJT-X.


I suspect, but do not know for sure, (maybe the designer can enlighten us) that 
there is insufficient delay in the (analog) signal path and the noise gets 
through before blanking takes place.


Wes  N7WS



On 9/3/2017 9:18 AM, K9MA wrote:

I have never found the K3 noise blanker to be effective.  On the other hand, in 
side-by-side comparisons, the noise blanker in my old FT-1000D can be very 
effective on my ever present power line noise.  However, like all noise 
blankers of that design, it only works if there are no strong signals within 
many kHz of the operating frequency, so it's completely useless on a crowded 
band.  The only way around this I know of is to use a second receiver, tuned to 
a clear spot nearby, to control the noise blanker.

BTW, the K3 noise blanker uses a filter with a bandwidth of about 100 kHz.  The 
idea is that, in such a wide bandwidth, the amplitude of the noise pulses 
should be large, making them easier to distinguish from signals.  (The FT-1000 
uses something like 15 kHz.)  However, I've never been able to get the K3 NB to 
work, even on a completely dead band.  Under the same conditions, I can often 
get a 20 dB reduction with the other radio.  That I don't understand.  I should 
investigate that sometime.

73,

Scott K9MA

--

Scott Ellington

  


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Re: [Elecraft] Noise Blankers

[Fred Jensen]

I find the K3 NB to be surprisingly effective.  I also find that 
adjustment is highly dependent on the characteristics of the signal and 
the noise, and the effects of changing those adjustments is subtle.  The 
effect of a blanker on ignition noise was really astounding ... "was," 
because ignition noise seems to be history these days.  I suspect that 
many of the "it doesn't work very well" observations may stem from 
anticipation of a dramatic disappearance of today's noise from 
incidental and unintended radiators with NB on.  My local noise comes 
from the NV Energy power system and an uncountable number of Part 15 
violators in the house and neighborhood.  K3 NB is very effective for me 
against them.


I am a bit sorry that both the IF and DSP blanker parameters are so 
cryptic in the K3.  Depth of the blanking pulse and width of the 
blanking interval are the two "real" parameters involved.  The K3 seems 
to camouflage them which, for me at least, makes them a bit harder to 
adjust properly, I'm not sure what I'm doing when I change them.  
Incidentally, punching holes in the receiver sensitivity to block noise 
pulses is itself introducing noise.  As with everything else in life, 
it's a trade-off.


73,

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

On 9/3/2017 9:40 AM, Jim Brown wrote:

On 9/3/2017 9:18 AM, K9MA wrote:

I have never found the K3 noise blanker to be effective.



BTW, the K3 noise blanker uses a filter with a bandwidth of about 100 
kHz.



The K3 NB is really TWO blankers, operating in two different IFs. Each 
can be tweaked for various kinds of noise from the menu system.  
Access the menu by a Long Push of the NB button.


It's important to understand that there are many kinds of noise. Noise 
blankers are most effective on IMPULSE NOISE, which is the result of 
something arcing, usually in the power system, but also electric 
fences and neon signs.


Most of the residential noise we hear today is ELECTRONIC noise, 
generated by switch-mode power supplies and microprocessors. Noise 
blankers must be very different to suppress this sort of noise. The 
menu tweaks provided by the K3, K3S, KX3, and KX2 are very critical to 
making the NB effective on the noise you're experiencing. One size 
does NOT fit all.


73, Jim K9YC 


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Re: [Elecraft] Noise Blankers

[Jim Brown]

On 9/3/2017 9:18 AM, K9MA wrote:

I have never found the K3 noise blanker to be effective.




BTW, the K3 noise blanker uses a filter with a bandwidth of about 100 kHz.



The K3 NB is really TWO blankers, operating in two different IFs. Each 
can be tweaked for various kinds of noise from the menu system.  Access 
the menu by a Long Push of the NB button.


It's important to understand that there are many kinds of noise. Noise 
blankers are most effective on IMPULSE NOISE, which is the result of 
something arcing, usually in the power system, but also electric fences 
and neon signs.


Most of the residential noise we hear today is ELECTRONIC noise, 
generated by switch-mode power supplies and microprocessors.  Noise 
blankers must be very different to suppress this sort of noise. The menu 
tweaks provided by the K3, K3S, KX3, and KX2 are very critical to making 
the NB effective on the noise you're experiencing. One size does NOT fit 
all.


73, Jim K9YC


On Sep 3, 2017, at 10:37 AM, Rick Tavan  wrote:

Noise blankers are difficult to design and to use. They work by blanking
out the receiver during noise pulses. The user defines what is a noise
pulse and how aggressively to blank it by adjusting the NB parameters.

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[Elecraft] Noise Blankers

[K9MA]

I have never found the K3 noise blanker to be effective.  On the other hand, in 
side-by-side comparisons, the noise blanker in my old FT-1000D can be very 
effective on my ever present power line noise.  However, like all noise 
blankers of that design, it only works if there are no strong signals within 
many kHz of the operating frequency, so it's completely useless on a crowded 
band.  The only way around this I know of is to use a second receiver, tuned to 
a clear spot nearby, to control the noise blanker.

BTW, the K3 noise blanker uses a filter with a bandwidth of about 100 kHz.  The 
idea is that, in such a wide bandwidth, the amplitude of the noise pulses 
should be large, making them easier to distinguish from signals.  (The FT-1000 
uses something like 15 kHz.)  However, I've never been able to get the K3 NB to 
work, even on a completely dead band.  Under the same conditions, I can often 
get a 20 dB reduction with the other radio.  That I don't understand.  I should 
investigate that sometime.

73, 

Scott K9MA 

--

Scott Ellington

 --- via iPad

> On Sep 3, 2017, at 10:37 AM, Rick Tavan  wrote:
> 
> Noise blankers are difficult to design and to use. They work by blanking
> out the receiver during noise pulses. The user defines what is a noise
> pulse and how aggressively to blank it by adjusting the NB parameters. If
> you don't blank out enough, you still hear the noise. If the signal is
> below that noise, you won't hear it. If you blank out too much, you lose so
> much real signal that it is no longer possible to copy or to copy
> comfortably. *I have had very good results with the NB in the K3 on some
> kinds of human-made noise.* Other noises seem to have too high a duty cycle
> or signal strength to be effectively blanked. Your noise sources may be in
> that category. I don't think it is fair to say the K3 NB "doesn't work." It
> certainly does work on many kinds of noise. No NB that I have tried or
> heard of can work on all kinds of noise.
> 
> 73,
> 
> /Rick N6XI
> 
> 
> Rick Tavan
> Truckee, CA
> 
> On Sun, Sep 3, 2017 at 8:12 AM, Gian Luca Cazzola 
> wrote:
> 
>> To Wayne and his Elecraft crew:
>> 
>> I am an ultra satisfied cw user of a Elecraft K3S ( that I use with P3 and
>> two SP3).
>> 
>> The only things that I dont like are:
>> - the noise blanker - i havent found situations where it help - or I am
>> unable to use it, even if I tried lot of settings…
>> 
>> - the NOISE REDUCTOR, that first times I thought it help barely, but after
>> some time I found that it simply need to be reset (simple OFF-ON) at band
>> noise changing  time after time and it work well.
>> 
>> About the NB I dont ask anything ( I simply accept that it doesn’t work),
>> 
>> but about NR - Noise Reductor I ask you that with next firmware
>> modifications you introduce an automatic NR reset ( at least every 5
>> minutes a ciclic OFF-ON, it simply improve a lot its results)
>> 
>> Many thanks.
>> 
>> 73 es gl,
>> Ian IK4EWX
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Re: [Elecraft] Noise Blankers

[Mike]

Radio Amateur N5GE wrote:
 On Thu, 7 Jan 2010 11:34:50 -0800 (PST), Wes Stewart n...@yahoo.com
 wrote:

   
 One of the tricks pulled on new
 guys was a customer or another salesman asking for a set of spark plugs
 for a Cummins, a radiator cap for a Corvair or an oil pan gasket for a
 Powerglide transmission.

 All of which don't exist.

 Wes  N7WS

 

 And in the aircraft mechanic trade we sent them out to get a bucket of
 prop wash ;o)
   
Y'all didn't use flight line to tie that bucket under the nacelle?

73, Mike NF4L

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Re: [Elecraft] Noise Blankers

[Steve Ellington]

I worked in a TV factory, 1968. We sent the new guys to the supply window 
for a raster stretcher.

Steve
N4LQ
n...@carolina.rr.com
- Original Message - 
From: gdaug...@stanford.edu
To: elecraft@mailman.qth.net
Sent: Friday, January 08, 2010 1:06 AM
Subject: Re: [Elecraft] Noise Blankers


 Hi all,

 All of which don't exist.

 And in the aircraft mechanic trade we sent them out to get a bucket of
 prop wash ;o)

 And in the electronics trade (tube days) we sent them out to get a drip 
 pan for grid
 leak resistors.

 73,

 George T Daughters, K6GT
 CU in the California QSO Party (CQP)
 October 2-3, 2010


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Checked by AVG - www.avg.com
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Re: [Elecraft] Noise Blankers

[Radio Amateur N5GE]

On Fri, 08 Jan 2010 08:23:01 -0500, Mike n...@nf4l.com wrote:

[snip]

   
Y'all didn't use flight line to tie that bucket under the nacelle?

73, Mike NF4L

Yes, but we did that before the prop wash trick.  When we sent them
for prop wash we sent them to the flight line, the location of which
they now knew.

And when I worked on the Harris 4 color press at Gulf Printing in
Houston, we would send the new guys upstairs to meet our stripper.

Great fun ;o)

Tom, N5GE

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Re: [Elecraft] Noise Blankers

[George Jan]

Early days of TV Broadcasting we sent new projectionists to the competition 
to get a box of sprocket holes - they always came back with them!
But when we sent them for a camera cable stretcher (does exist) they 
wouldn't go.

George
AI4VZ


Hi all,

 All of which don't exist.

 And in the aircraft mechanic trade we sent them out to get a bucket of
 prop wash ;o)

And in the electronics trade (tube days) we sent them out to get a drip pan 
for grid
leak resistors. 

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[Elecraft] Noise Blankers

[eric norris]

Tom,

I find the noise blanker on the K3 to be extremely good.  I have been plagued 
with power line noise for years at my QTH, and the K3 is the first rig I've 
owned that can knock it out.  It takes a bit of tweaking, and for reasons I 
don't understand the power line noise on Tuesday night might require a 
different setting than the power line noise on Monday night.  During the 
Geminids meteor shower last month I had some strange impulse noise that would 
have wiped me out with my previous rigs.  With the K3's noise blanker I was 
able to carefully remove it without destroying the weak-signal capability and 
worked a pile of stations on 6m meteor scatter. 

Try one out--you'll love it!

73 Eric WD6DBM   
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Re: [Elecraft] Noise Blankers

[David Olean]

Hello Tom,
I am plagued by excessive amounts of power line noise on 50, 144 and 
222MHz. It has been going on for years to the point where the FCC  (both 
Riley Hollingsworth and Laura Smith) have sent letters to the local utility. 
I have used several receivers and none really took out the noise as 
effectively as the K3 has. I find that for my situation, the DSP blanker is 
quite good when things get bad.  In the past I have seen other noise 
blankers get swamped out by so many noise pulses that they have lost 
effectiveness. Simple noises of maybe one or two arcing points can be 
removed, but 7 or 8 is another story. As more noise comes on, the blankers 
fare more poorly.  (Yes, one power pole can have 7 or 8 points that are 
generating rfi)  With the K3, I have been able to negate most of the noise 
and still am able to operate through the noise by adjusting the DSP NR 
settings along with IF blanking. I find that the DSP NR works better for my 
situation. My antennas are high and in the clear. The worst noise problem 
has come from a 34.5 KV line that is seven miles from my antenna. It is 
typically peaking S7 and is composed of many arcing tie wires and leaking 
insulators. Only the K3 has removed this noise as a factor in receiving. My 
other radios with only IF blanking do absolutely nothing to the noise in 
that direction.
The nice thing is that you can tailor the effect on the fly and 
immediately tell which setting works best.  I am pleased with the DSP as it 
does not overload with strong signals. While it makes the audio sound 
somewhat ugly at aggressive settings, the overall outcome is positive. I am 
more than happy with the noise performance of the K3. It is quite a tool.  I 
believe the Flex Radio is another stellar performer in this area, but I have 
not tried it at my QTH.

Dave K1WHS

- Original Message - 
From: Tom Bickley k...@hotmail.com
To: elecraft@mailman.qth.net
Sent: Thursday, January 07, 2010 1:38 AM
Subject: [Elecraft] Noise Blankers



 I'm overdue for a new radio (at least, that's what I am telling my
 XYL). In considering the purchase, unfortunately one of the major
 considerations I must take into account is
 the noise blanker function. I have recently moved to an area with A LOT
 of power line noise. I have high voltage lines around my immediate QTH.
 It is a constant S3 to S5 on all bands above 7 MHz and, sometimes on
 really
 cold mornings, a seperate, additional noise kicks in that takes it to
 S9 or more. I am trying to locate these noise sources but have been
 unable to so far. I must run the noise blanker on my old TS-850s at all 
 times to help me manage this problem. With the NB engaged (which
 is 'always') I have audio distortion created from nearby signals,
 especially stronger  signals within 30
 kc's of my receive frequency, no matter at what level I run either of the 
 noise
 blankers.

 I would like to hear from K3 owners who might have
 'line noise problems' and know how the noise blanker in your K3 handles
 the problem.

 Mni Tnx / 73   K4NA

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Re: [Elecraft] Noise Blankers

[Guy Olinger K2AV]

A six cylinder diesel doesn't have ignition noise.  What noise are you
comparing against?  73, Guy.

On Wed, Jan 6, 2010 at 11:38 PM,  rfenab...@gmail.com wrote:
 To be honest I have not found any noise the NB would not get rid of.

 Having said that, I have a 6 cylinder diesel that does give my TS-480SAT some 
 measure of grief.

 Just for my own knowledge I hooked the K3 to the same power lead fitted with 
 Anderson plugs as with all my power leads, and, the result was impressive.

 Where the 480 was struggling the K3 shone and I was happy with the result.

 From this you can surmise that the K3 NB is very effective on ignition noise.

 Hope you are getting good information to help you decide.

 73's and good luck whichever way you jump.

 Gary
 VK4FD
 Sent via BlackBerry® from Telstra
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Re: [Elecraft] Noise Blankers

[Matt Zilmer]

A diesel fuel injection pump/system makes all kinds of electrical
noise.  There is no electrical ignition system in a diesel engine.

73,
matt, W6NIA

On Thu, 07 Jan 2010 12:47:52 -0500, you wrote:

A six cylinder diesel doesn't have ignition noise.  What noise are you
comparing against?  73, Guy.

On Wed, Jan 6, 2010 at 11:38 PM,  rfenab...@gmail.com wrote:
 To be honest I have not found any noise the NB would not get rid of.

 Having said that, I have a 6 cylinder diesel that does give my TS-480SAT 
 some measure of grief.

 Just for my own knowledge I hooked the K3 to the same power lead fitted with 
 Anderson plugs as with all my power leads, and, the result was impressive.

 Where the 480 was struggling the K3 shone and I was happy with the result.

 From this you can surmise that the K3 NB is very effective on ignition 
 noise.

 Hope you are getting good information to help you decide.

 73's and good luck whichever way you jump.

 Gary
 VK4FD
 Sent via BlackBerry® from Telstra
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Re: [Elecraft] Noise Blankers

[Radio Amateur N5GE]

On Thu, 7 Jan 2010 12:47:52 -0500, Guy Olinger K2AV
olin...@bellsouth.net wrote:

A six cylinder diesel doesn't have ignition noise.  What noise are you
comparing against?  73, Guy.



 Having said that, I have a 6 cylinder diesel that does give my TS-480SAT 
 some measure of grief.
[snip]

Guy and all,

If the diesel has electronically timed injectors, the injector timing
circuitry could be causing noise.

Tom, N5GE

n...@n5ge.com
K3 #806 with SUB RX, K3 #1055, PR6,
XV144, XV432, KRC2,
W1, 2 W2's and other small kits

1 K144XV on order

http://www.n5ge.com
http://www.swotrc.net

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Re: [Elecraft] Noise Blankers

[Wes Stewart]

--- On Thu, 1/7/10, Guy Olinger K2AV olin...@bellsouth.net wrote:


 A six cylinder diesel doesn't have
 ignition noise.  

Actually,
some old International Harvester diesels did have spark plugs.  They
started on gasoline and after they warmed up, the operator switched
them over to diesel :-)

Otherwise, this reminds me of a story. 
When I was a teenager, my dad, who managed a large automotive machine
shop associated with an automotive and industrial parts store, got me a
summer job there as a parts guy.

One of the tricks pulled on new
guys was a customer or another salesman asking for a set of spark plugs
for a Cummins, a radiator cap for a Corvair or an oil pan gasket for a
Powerglide transmission.

All of which don't exist.

Wes  N7WS



  
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Re: [Elecraft] Noise Blankers

[Radio Amateur N5GE]

On Thu, 7 Jan 2010 11:34:50 -0800 (PST), Wes Stewart n...@yahoo.com
wrote:

One of the tricks pulled on new
guys was a customer or another salesman asking for a set of spark plugs
for a Cummins, a radiator cap for a Corvair or an oil pan gasket for a
Powerglide transmission.

All of which don't exist.

Wes  N7WS


And in the aircraft mechanic trade we sent them out to get a bucket of
prop wash ;o)

Tom, N5GE

n...@n5ge.com
K3 #806 with SUB RX, K3 #1055, PR6,
XV144, XV432, KRC2,
W1, 2 W2's and other small kits

1 K144XV on order

http://www.n5ge.com
http://www.swotrc.net

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Re: [Elecraft] Noise Blankers

[gdaught6]

Hi all,

 All of which don't exist.

 And in the aircraft mechanic trade we sent them out to get a bucket of
 prop wash ;o)

And in the electronics trade (tube days) we sent them out to get a drip pan for 
grid 
leak resistors.

73,

George T Daughters, K6GT
CU in the California QSO Party (CQP)
October 2-3, 2010


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[Elecraft] Noise Blankers

[Tom Bickley]

I'm overdue for a new radio (at least, that's what I am telling my
XYL). In considering the purchase, unfortunately one of the major
considerations I must take into account is
the noise blanker function. I have recently moved to an area with A LOT
of power line noise. I have high voltage lines around my immediate QTH.
It is a constant S3 to S5 on all bands above 7 MHz and, sometimes on
really
cold mornings, a seperate, additional noise kicks in that takes it to
S9 or more. I am trying to locate these noise sources but have been
unable to so far. I must run the noise blanker on my old TS-850s at all times 
to help me manage this problem. With the NB engaged (which
is 'always') I have audio distortion created from nearby signals,
especially stronger  signals within 30
kc's of my receive frequency, no matter at what level I run either of the noise
blankers. 

I would like to hear from K3 owners who might have
'line noise problems' and know how the noise blanker in your K3 handles
the problem.  

Mni Tnx / 73   K4NA  
  
_
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Re: [Elecraft] Noise Blankers

[Wayne Burdick]

Hi Tom,

You'll get a lot of opinions on noise blankers, I suspect :)

Here's my 2 cents: The K3's combination of two noise blankers -- one  
at the 1st IF and one at the DSP -- can work wonders on all sorts of  
noise. But it's especially good with power-line noise (loads of that  
at my QTH). The K3 doesn't pre-filter down to 15 kHz, which means the  
sharp pulse rise-times are preseved. This means you can typically keep  
the IF blanker's threshold very high, minimizing the type of IMD that  
all IF blankers cause. The DSP blanker is icing on the cake,  
especially if you also have complex noise like that from switching  
supplies, etc. (stuff that drifts a lot).

That said, I suggest you borrow a K3 and try it at your QTH. We can  
find a nearby K3 owner for you, or you can ask on the reflector.

Good luck with whatever rig you choose, and don't hesitate to post  
further questions.

73,
Wayne
N6KR

On Jan 6, 2010, at 5:38 PM, Tom Bickley wrote:


 I'm overdue for a new radio (at least, that's what I am telling my
 XYL). In considering the purchase, unfortunately one of the major
 considerations I must take into account is
 the noise blanker function. I have recently moved to an area with A  
 LOT
 of power line noise. I have high voltage lines around my immediate  
 QTH.
 It is a constant S3 to S5 on all bands above 7 MHz and, sometimes on
 really
 cold mornings, a seperate, additional noise kicks in that takes it to
 S9 or more. I am trying to locate these noise sources but have been
 unable to so far. I must run the noise blanker on my old TS-850s at  
 all times to help me manage this problem. With the NB engaged (which
 is 'always') I have audio distortion created from nearby signals,
 especially stronger  signals within 30
 kc's of my receive frequency, no matter at what level I run either  
 of the noise
 blankers.

 I would like to hear from K3 owners who might have
 'line noise problems' and know how the noise blanker in your K3  
 handles
 the problem.

 Mni Tnx / 73   K4NA  
   
 _
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 http://clk.atdmt.com/GBL/go/196390710/direct/01/
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Re: [Elecraft] Noise Blankers

[Duncan Carter]

The K3 blankers have a considerable range of adjustability of both the 
blanking threshold with seven steps, and the blanking pulse width with 
three steps, with independent settings for hardware blanking and dsp 
blanking.  Hopefully, you can find a setting that will work without 
excess distortion but that may not always be the case if the noise is 
relatively low and the inband signals are not.  There is a learning 
curve.  Blanker effectiveness was one of my criteria  for selecting the K3.

73, Dunc, W5DC

Tom Bickley wrote:
 I'm overdue for a new radio (at least, that's what I am telling my
 XYL). In considering the purchase, unfortunately one of the major
 considerations I must take into account is
 the noise blanker function. I have recently moved to an area with A LOT
 of power line noise. I have high voltage lines around my immediate QTH.
 It is a constant S3 to S5 on all bands above 7 MHz and, sometimes on
 really
 cold mornings, a seperate, additional noise kicks in that takes it to
 S9 or more. I am trying to locate these noise sources but have been
 unable to so far. I must run the noise blanker on my old TS-850s at all times 
 to help me manage this problem. With the NB engaged (which
 is 'always') I have audio distortion created from nearby signals,
 especially stronger  signals within 30
 kc's of my receive frequency, no matter at what level I run either of the 
 noise
 blankers. 

 I would like to hear from K3 owners who might have
 'line noise problems' and know how the noise blanker in your K3 handles
 the problem.  

 Mni Tnx / 73   K4NA
 
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Re: [Elecraft] Noise Blankers

[Matt Zilmer]

Hi Tom,

Well, I have a K3 noise blanker story for you.

About two months ago, I suddenly had an S9+20 line noise problem
around here.  I knew it was some type of failed Edison equipment, or
maybe something at a residence.  It was loud enough to hear with a
stubby for ANT1, and on 80m through 30m under any conditions.

I had to diddle the K3's noise blanker a bit to get it dialed in
right, but I finally killed the crud on the Main and Sub receivers.
There was a residual amount of distortion;  I had never run the NB
this aggressively before - never had to.  However, effectively the
noise was blanked down to S7 or so on 40m where it was the worst.  And
it made 80m usable again on CW...

In a few days, an Edison power quality tech came out and located the
noise source.  Some customer-owned (but unused) transformers on a
citrus farm a few blocks from us had open primaries.  He had the feed
to them disconnected and notified the owner that they needed to be
replaced (they weren't working anyway).  These transformers were used
to power irrigation pumps, so the owner got the problem cleared up
right away.  

I was completely amazed how well the NB works under very difficult
conditions.  May no one else have to find out how well this feature
works in the same way or for a similar reason.

73,
matt W6NIA
K3 #24
K2 #2810

Except for being a paying customer, I have no formal affiliation with
Elecraft.


On Thu, 07 Jan 2010 01:38:35 +, you wrote:


I'm overdue for a new radio (at least, that's what I am telling my
XYL). In considering the purchase, unfortunately one of the major
considerations I must take into account is
the noise blanker function. I have recently moved to an area with A LOT
of power line noise. I have high voltage lines around my immediate QTH.
It is a constant S3 to S5 on all bands above 7 MHz and, sometimes on
really
cold mornings, a seperate, additional noise kicks in that takes it to
S9 or more. I am trying to locate these noise sources but have been
unable to so far. I must run the noise blanker on my old TS-850s at all times 
to help me manage this problem. With the NB engaged (which
is 'always') I have audio distortion created from nearby signals,
especially stronger  signals within 30
kc's of my receive frequency, no matter at what level I run either of the noise
blankers. 

I would like to hear from K3 owners who might have
'line noise problems' and know how the noise blanker in your K3 handles
the problem.  

Mni Tnx / 73   K4NA 
 
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Re: [Elecraft] Noise Blankers

[Mike]

Tom,
I'm a new K3 owner, coming from an ICOM PRO II, and still learning how 
to use the K3. I live with a pretty constant S9 or better noise level. I 
think most of it is power line.

Whatever it is, the NB on the K3 knocks the cover off  the ICOM.

73, Mike NF4L

Tom Bickley wrote:
 I'm overdue for a new radio (at least, that's what I am telling my
 XYL). In considering the purchase, unfortunately one of the major
 considerations I must take into account is
 the noise blanker function. I have recently moved to an area with A LOT
 of power line noise. I have high voltage lines around my immediate QTH.
 It is a constant S3 to S5 on all bands above 7 MHz and, sometimes on
 really
 cold mornings, a seperate, additional noise kicks in that takes it to
 S9 or more. I am trying to locate these noise sources but have been
 unable to so far. I must run the noise blanker on my old TS-850s at all times 
 to help me manage this problem. With the NB engaged (which
 is 'always') I have audio distortion created from nearby signals,
 especially stronger  signals within 30
 kc's of my receive frequency, no matter at what level I run either of the 
 noise
 blankers. 

 I would like to hear from K3 owners who might have
 'line noise problems' and know how the noise blanker in your K3 handles
 the problem.  

 Mni Tnx / 73   K4NA
 
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 Hotmail: Powerful Free email with security by Microsoft.
 http://clk.atdmt.com/GBL/go/196390710/direct/01/
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[Elecraft] Noise Blankers

[rfenabled]

To be honest I have not found any noise the NB would not get rid of.

Having said that, I have a 6 cylinder diesel that does give my TS-480SAT some 
measure of grief.

Just for my own knowledge I hooked the K3 to the same power lead fitted with 
Anderson plugs as with all my power leads, and, the result was impressive.

Where the 480 was struggling the K3 shone and I was happy with the result.

From this you can surmise that the K3 NB is very effective on ignition noise.

Hope you are getting good information to help you decide.

73's and good luck whichever way you jump.

Gary
VK4FD
Sent via BlackBerry® from Telstra
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