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Mike Smith VE9AA

NB issue

Yes, it's a K3 early serial #.....I just got it yesterday. (sorry about that
- I forgot it was an Elecraft wide list and not just a K3 list - my bad)

I updated the firmware from 4.83 to the newest a couple hours ago, hoping it
would help.

Good on eliminating the mention on newer firmware. That's a relief.

The noise I am trying to clear up is a nearby electric fence.

So far as I can tell, the IF NB does nothing (or very nearly next to
nothing).

Regardless of the dozen or whatever choices and any other setting on the
radio be it mode, width, gain, whatever, the NB letters themselves will
flash once I transmit a couple times.

I have even put the rig down to 5W thinking MAYBE it was RFI, but that would
not explain the NB doing nothing (or very nearly nothing) in RX mode before
I even transmit once.

A rig sitting right next to it from an Asian country eliminates the pulses
easily and I have been told the K3 is way better. I have to believe that.

One thing did occur to me as I was typing this. The radio was shipped to me
(packed very well ) by Canada Post.

Could this particular board KNB3 be loose on a connector?

Has nobody ever seen this particular issue? I can't imagine in all these
years I would be the first to see this issue, hi !

Other than the NB, the radio works very well, so the board is in there - but
it's just not doing its job, hi

73 es thanks a lot guys. So far, I am liking the radio...unfortunately for
me, an electric fence is my nemesis.

Mike VE9AA

Mike, Coreen & Corey

Keswick Ridge, NB

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Elecraft mailing list

Re: NB issue

Hmmm, those NB letters are not supposed to flash. They should either be on or off. Sounds like a bad connection someplace.

To eliminate RF causing any sort of problem, please try transmitting into a dummy load.

73 from David GM4JJJ

> On 15 May 2016, at 23:14, Mike Smith VE9AA <[hidden email]> wrote:
>
> Regardless of the dozen or whatever choices and any other setting on the
> radio be it mode, width, gain, whatever, the NB letters themselves will
> flash once I transmit a couple times.

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Nr4c

Re: NB issue

What effect do you expect when transmitting? I would think "nothing" since NB is a Receive function.

Sent from my iPhone
...nr4c. bill

> On May 15, 2016, at 6:43 PM, David Anderson via Elecraft <[hidden email]> wrote:
>
> Hmmm, those NB letters are not supposed to flash. They should either be on or off. Sounds like a bad connection someplace.
>
> To eliminate RF causing any sort of problem, please try transmitting into a dummy load.
>
> 73 from David GM4JJJ
>
>> On 15 May 2016, at 23:14, Mike Smith VE9AA <[hidden email]> wrote:
>>
>> Regardless of the dozen or whatever choices and any other setting on the
>> radio be it mode, width, gain, whatever, the NB letters themselves will
>> flash once I transmit a couple times.
>
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Mike Smith VE9AA

Re: NB issue

I am not sure what you are eluding to Bill, but suffice to say I don;'t
think you understand the issue.
Once I have transmitted, the NB flashes and will stay flashing forever.
(while I am sitting there receiving)
Also, the NB seems to do little to nothing.

I am not a K3 engineer, but I am now SURE this is not how it's supposed to
work.

I am going to crack the radio open tomorrow and see if the board has come
loose during shipping.

Please don't anyone email me again asking me to look at the page in the
manual concerning the NB. (I have had a number of you do that and
even send me a copy of the page. )

I give you my word I have read it and have read it again!. Regardless of
settings the NB letters flash. (when invoking IF NB_)

Something is not correct :-)

Mike VE9AA

Mike, Coreen & Corey
Keswick Ridge, NB

-----Original Message-----
From: Nr4c [mailto:[hidden email]]
Sent: May 15, 2016 8:00 PM
To: David Anderson
Cc: Mike Smith VE9AA; [hidden email]
Subject: Re: [Elecraft] NB issue

What effect do you expect when transmitting? I would think "nothing" since
NB is a Receive function.

Sent from my iPhone
...nr4c. bill

> On May 15, 2016, at 6:43 PM, David Anderson via Elecraft
<[hidden email]> wrote:
>
> Hmmm, those NB letters are not supposed to flash. They should either be on
or off. Sounds like a bad connection someplace.
>
> To eliminate RF causing any sort of problem, please try transmitting into
a dummy load.

>
> 73 from David GM4JJJ
>
>> On 15 May 2016, at 23:14, Mike Smith VE9AA <[hidden email]> wrote:
>>
>> Regardless of the dozen or whatever choices and any other setting on
>> the radio be it mode, width, gain, whatever, the NB letters
>> themselves will flash once I transmit a couple times.
>
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Oliver Dröse

Re: NB issue

In reply to this post by Mike Smith VE9AA

Hey Mike,

good to see you here, too. ;-)

> A rig sitting right next to it from an Asian country eliminates the
pulses
> easily and I have been told the K3 is way better. I have to believe that.

Forget it! As much as I like my K3 (and I really do!) the NB + NR are
the worst I ever experienced. The Icom NB is running circles around it
... just to put your expectations where they belong. ;-)

Besides this you'll probably love the radio ... as do I. ;-)

73, Olli - DH8BQA

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Re: NB issue

In reply to this post by Mike Smith VE9AA

Mike,

I think Bill was alluding to my answer which on the face of it didn't make any sense, but what I was trying to determine was whether stray RF may have been doing something to the K3 NB circuitry during transmit as you suggested you thought the NB started to flash after transmitting, hence my suggestion to eliminate any possibility by using a dummy load, that's all.

Now thanks to the group we have the correct answer, the NB annunciation legend can flash when the I.F. blanker setting is too high for the signals. It will stop flashing when transmitting and start again back on receive.

I should have searched the electronic manual, that is what I generally do in iBooks on the iPad where I keep all my radio manuals. It is generally easier than manually searching the paper copy which is safely stored away in a file.

I don't own a K3, hence me not knowing about the significance of the flashing NB, I use the KX3 and find the noise blanker works very well on powerline noise, narrow pulses, ignition spark type noise. I would find it strange and disappointing if the K3's blanker was poorer than the KX3's.

What is puzzling is that you say it electric fence pulses that the NB is struggling with, I would have thought that is one of the easiest things to blank out, a simple I.F. Blanker shouldn't have a problem with that.

Like so many controls that give you a lot of user settings there are benefits and also problems, mostly the defaults are a good starting point, but changing too many settings at once will not help. You have to be methodical and change one thing at a time and see what the effect if any is.

I have used the KX3 as my main rig for more than a year and am still finding things about it that I didn't know. It's part of the joy.

73 from David GM4JJJ

> On 16 May 2016, at 00:06, Mike Smith VE9AA <[hidden email]> wrote:
>
> I am not sure what you are eluding to Bill, but suffice to say I don;'t
> think you understand the issue.
> Once I have transmitted, the NB flashes and will stay flashing forever.
> (while I am sitting there receiving)
> Also, the NB seems to do little to nothing.
>
> I am not a K3 engineer, but I am now SURE this is not how it's supposed to
> work.
>
> I am going to crack the radio open tomorrow and see if the board has come
> loose during shipping.
>
> Please don't anyone email me again asking me to look at the page in the
> manual concerning the NB. (I have had a number of you do that and
> even send me a copy of the page. )
>
> I give you my word I have read it and have read it again!. Regardless of
> settings the NB letters flash. (when invoking IF NB_)
>
> Something is not correct :-)
>
> Mike VE9AA
>
> Mike, Coreen & Corey
> Keswick Ridge, NB
>
>
> -----Original Message-----
> From: Nr4c [mailto:[hidden email]]
> Sent: May 15, 2016 8:00 PM
> To: David Anderson
> Cc: Mike Smith VE9AA; [hidden email]
> Subject: Re: [Elecraft] NB issue
>
> What effect do you expect when transmitting? I would think "nothing" since
> NB is a Receive function.
>
> Sent from my iPhone
> ...nr4c. bill
>

Oliver Dröse

Re: NB issue

Hi David,

> I don't own a K3, hence me not knowing about the significance of the flashing NB, I use the KX3 and find the noise blanker works very well on powerline noise, narrow pulses, ignition spark type noise. I would find it strange and disappointing if the K3's blanker was poorer than the KX3's.

I have both and the KX3's NB is definitely much better than the K3's
(although still worse than the Icom NBs). Probably a question of the
newer DSP chip in the KX3 and maybe updated DSP code, too (on which
Lyle, KK7P, could chime in).

73, Olli - DH8BQA

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K9MA

K3 NB

On 5/16/2016 04:40, Oliver Dröse wrote:
> I have both and the KX3's NB is definitely much better than the K3's
> (although still worse than the Icom NBs). Probably a question of the
> newer DSP chip in the KX3 and maybe updated DSP code, too (on which
> Lyle, KK7P, could chime in).

One of the (few) disappointments of my K3 is the NB. I've never found
any settings which are effective against power line noise under any
conditions, even on a quiet band. My old FT-1000D NB, on the other
hand, can be very effective against that same noise, provided the band
isn't full of strong signals. Neither is useful in contests, of
course. Given the way the NB's in both transceivers work (wide filter
ahead of NB), neither can be effective with strong signals nearby. My
dream is that Elecraft could provide a way to use the subreceiver to
detect noise outside the band, and control the NB in the main receiver.
Or perhaps some day I'll figure out how to do that myself. However,
first the K3 NB has to work in the absence of strong signals, which it
does not.

--
Scott Ellington K9MA
Madison, Wisconsin, USA

[hidden email]

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riese-k3djc

Re: K3 NB

lots of opinions,,, what I take away is regardless of the update ( I am
woefully behind )
the NB on the K3 doesnt work well on power line noise,,, this is my
experience as well
but I am behind on the software upgrades

Bob K3DJC

> One of the (few) disappointments of my K3 is the NB. I've never
> found
> any settings which are effective against power line noise under any
>
> conditions,

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k6dgw

Re: K3 NB

Noise blankers have never worked well, or at all, on most power line
noise which is usually caused by very small arcing in the distribution
line [usually around 12 KV in the US] hardware on the poles. It's
multiple arcs, and the noise pulses from each one overlap each other
producing the rough buzz.

The K3 IF NB worked far better than great for me when I was surrounded
by electric fences and it's puzzling that anyone is having problems
getting it to work. Ignition noise tends to be a thing of the past, but
in the few times I've encountered it. the NB was extremely effective as
well, and easy to adjust.

I don't remember who first came up with it ... I thin Art Collins had
some role ... but it was light years ahead of the old Lamb Noise
Limiters such as in the SX-28.

73,

Fred K6DGW
- Northern California Contest Club
- CU in the Cal QSO Party 1-2 Oct 2016
- www.cqp.org

On 5/16/2016 8:57 AM, [hidden email] wrote:
>
> lots of opinions,,, what I take away is regardless of the update ( I am
> woefully behind )
> the NB on the K3 doesnt work well on power line noise,,, this is my
> experience as well
> but I am behind on the software upgrades
>
> Bob K3DJC

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Graham Kimbell

Re: K3 NB

In reply to this post by riese-k3djc

I'm really surprised by all these negative comments about K3 NB. Mine
has been very effective on electric fences (I have one!) and power line
noise.

Try this from 5 years ago:-
http://www.g3tct.co.uk/GB3ANG_processing.mp3

[you'll hear first the GB3ANG beacon on 70MHz (tropo, 607km) in ssb
bandwidth (2.3kHz) with no noise blanking. There's bad power line noise.
At 6.7seconds in, the noise blanker is switched on (set at dsp t2-6,
IF narrow 3). At 21.4secs in, the mode is switched to cw - the audio
tone remains the same, and the bandwidth changes to 900Hz. At 30.5secs
in, the APF is switched on until 56.4secs. At 61.5secs we revert to usb
mode and at 68.3secs, the noise blanker is turned off.]

73
Graham

On 19:59, [hidden email] wrote:
> ...
> the NB on the K3 doesnt work well on power line noise,,, this is my
> experience as well
>
>
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Ramon Tristani-2

Re: K3 NB

Banned User

Great recording. Just had to follow your email and listen to the sound at the same time. I have had my K3 for over five years now (Serial No. 4416), a kit that I put together myself, without ever having any problems whatsoever. For questions, a simple call to Elecraft Customer Support has sufficed, a reply with instructions and solutions, if any, have arrived within minutes. I have had Kenwoods, Icoms, Yaesus, Galaxy, Collins, you name it, and never ever have I dealt with such a dedicated company whose products are worth every penny I have paid for. They have to be commended for the high standards of quality and outstanding customer support. I have been a ham since the early sixties. My comment is based on my own experience. In all those years I have never dealt with a company and products that even compare to Elecraft. I only hope they are here to stay.

73,
Ramón E. Tristani Sr.
NQ9V (ex-KP4GE)

> On May 17, 2016, at 10:25 AM, Graham Kimbell <[hidden email]> wrote:
>
> I'm really surprised by all these negative comments about K3 NB. Mine has been very effective on electric fences (I have one!) and power line noise.
>
> Try this from 5 years ago:-
> http://www.g3tct.co.uk/GB3ANG_processing.mp3
>
> [you'll hear first the GB3ANG beacon on 70MHz (tropo, 607km) in ssb bandwidth (2.3kHz) with no noise blanking. There's bad power line noise. At 6.7seconds in, the noise blanker is switched on (set at dsp t2-6, IF narrow 3). At 21.4secs in, the mode is switched to cw - the audio tone remains the same, and the bandwidth changes to 900Hz. At 30.5secs in, the APF is switched on until 56.4secs. At 61.5secs we revert to usb mode and at 68.3secs, the noise blanker is turned off.]
>
> 73
> Graham
>
> On 19:59, [hidden email] wrote:
>> ...
>> the NB on the K3 doesnt work well on power line noise,,, this is my
>> experience as well
>>
>>
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Don Wilhelm

Re: K3 NB

In reply to this post by Graham Kimbell

The gentleman who was having problems has found the cause. He swapped
the KNB3 from the sub to the mainRX. In other words, the KNB3 in his
mainRX was not functioning properly.

Yes, the NB does not do too much for power line noise - it works well on
impulse type noise like automobile ignition noise and most types of
electric fence noise.

In other words, use NR for more constant type noises like powerline buzz.

73,
Don W3FPR

On 5/17/2016 10:25 AM, Graham Kimbell wrote:
> I'm really surprised by all these negative comments about K3 NB. Mine
> has been very effective on electric fences (I have one!) and power
> line noise.
>

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ab2tc

Re: K3 NB

Don Wilhelm wrote

The gentleman who was having problems has found the cause. He swapped
the KNB3 from the sub to the mainRX. In other words, the KNB3 in his
mainRX was not functioning properly.

Yes, the NB does not do too much for power line noise
<snip>

Hi Don,

That is not my experience at all. I sometimes have moderate power line noise and I find the DSP blanker, not IF, rather effective. I use settings between T2-5 to T2-7. The higher setting gives better suppression but distorts audio for moderately strong signals (S7). For a while I was using some additional IF blanking but soon decided it had virtually no additional benefits. This is on SSB with 300-2700Hz passband.

AB2TC - Knut

ab2tc

Re: K3 NB

ab2tc wrote

Don Wilhelm wrote

The gentleman who was having problems has found the cause. He swapped
the KNB3 from the sub to the mainRX. In other words, the KNB3 in his
mainRX was not functioning properly.

Yes, the NB does not do too much for power line noise
<snip>

Hi Don,

That is not my experience at all. I sometimes have moderate power line noise and I find the DSP blanker, not IF, rather effective. I use settings between T2-5 to T2-7. The higher setting gives better suppression but distorts audio for moderately strong signals (S7). For a while I was using some additional IF blanking but soon decided it had virtually no additional benefits. This is on SSB with 300-2700Hz passband.

AB2TC - Knut

Hi again,

I have reread this entire thread and I think I start to see what's going on. The KX3 only has a DSP noise blanker to my knowledge and some people who have both KX3 and K3 say the KX3 's NB is much better then the K3's for power line noise. I am guessing their K3 is set up for IF blanker only or with very little DSP assist. On the K3 the DSP NB works very well and I see the gentleman in the UK with the very convincing audio recording is using a little IF blanker assist. That audio recording is very much in agreement with what I am hearing when my power line noise is bad (usually on hot, humid summer days).

AB2TC - Knut

Guy Olinger K2AV

Re: K3 NB

In reply to this post by ab2tc

A lot of NB success on power line noise has to do with what state the noise
is in when it gets to you. If the source is near, and the waveform is not
smeared, the K3 NB does very well. The problem comes when a source is
rather distant, and is getting to you conducted over something like a mile
of primary transmission line. Then the waveform can be smeared and lacks
the crisp sharp peak that the circuitry and algorithms love and suppress so
neatly. This also accounts for a lot of variation in reporting. A smeared
noise waveform is very much harder to block out. Sometimes NR will do that
better, but this is very much an individual situation variance.

In my case there is sometime an arc at a pole about 3/4 miles from here
that belongs to the City of Apex power distribution. I don't hear it
directly from there. I hear it from lines close to me up and down 64, which
smears it. I also hear it from a line that runs beside Toll 540 at right
angles to me and from the other direction. More smearing. I did find that
with a certain combination of digital and IF NB, and sweeping the band,
that there were a couple 3-4 kHz wide spots where the stuff nulled out
pretty well. What was the difference? The change in frequency changed the
wavelengths and unsmeared the result at those two spots enough that the NB
could get it. So I worked a run frequency in the 160 contest in those two
narrow ranges, where the NB actually had things down to the normal band
noise level.

So reports that don't mention anything about the nature of the noise and
are at different locations can't be used to evaluate a noise blanker. Only
a side by side comparison and knowing the nature of the noise.

A "disadvantage" of sorts is the number of combinations possible on the K3.
In a conversation with a complainant on the K3 NB, I asked if the full
number of combinations had been tried. He said that was too many. He tried
a few and gave up. When I pressed on that, he said that radios shouldn't
have so many possibilities, that manufacturers should pick the right one
and just have that come up when the NB is hit.

When that Apex noise source started up before a contest, it took me a
couple of hours fiddling before I realized that certain settings produced
noise nulls in different places on the band. It took me a lot longer than
that to figure out what was going on (the smearing or not). Without all the
possible combinations, I would have either been lucky or not with what the
radio gave me.

And you can have a bad board. If that's it, your Elecraft service is top
flight.

Besides that your K3 NB can take out key clicks, and Elecraft is the only
one I know of that can do that.

73, Guy K2AV

On Tue, May 17, 2016 at 2:36 PM, ab2tc <[hidden email]> wrote:

> Don Wilhelm wrote
> > The gentleman who was having problems has found the cause. He swapped
> > the KNB3 from the sub to the mainRX. In other words, the KNB3 in his
> > mainRX was not functioning properly.
> >
> > Yes, the NB does not do too much for power line noise
> > <snip>
>
>
>
> Hi Don,
>
> That is not my experience at all. I sometimes have moderate power line
> noise
> and I find the DSP blanker, not IF, rather effective. I use settings
> between
> T2-5 to T2-7. The higher setting gives better suppression but distorts
> audio
> for moderately strong signals (S7). For a while I was using some additional
> IF blanking but soon decided it had virtually no additional benefits. This
> is on SSB with 300-2700Hz passband.
>
> AB2TC - Knut
>
>
>
> --
> View this message in context:
> http://elecraft.365791.n2.nabble.com/NB-issue-tp7617459p7617525.html
> Sent from the Elecraft mailing list archive at Nabble.com.
> ______________________________________________________________
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>

Re: K3 NB

In reply to this post by ab2tc

Another approach -like K2AV.

I suspect the reason there are so many differing opinions on the effectiveness for the K3NB
is that the noise pulses from an arcing piece of powerline hardware can be so different .

In fact the better powerline RFI folks now use a receiver that takes a picture of the waveform of
the interference you are hearing and they go in search of where that particular waveform is
being generated .The local APS guys ask if they can just connect to your antenna
and record exactly what you are hearing .

If you have an oscilloscope - I suggest you hang one across your speaker or headphone outputs
put the K3 on AM and widest filter , use the line sync and set to 10 msec/div .

Its interesting to watch the spikes versus what you are hearing . Obviously the K3 NB setting
will be different for different kinds of spiking . I have seen cases where there will be 3 and 4
spikes spaced about a half to maybe a msec apart repeating every 16.6 msec .And
this can and usually is be imtermittent The blanker
window can obviously be different than for a single pulse evey 16.6 msec. And the wider
the blanking - the more of the desired signal gets chopped.

The problem with NB in any receiver I have ever had is that a very effective blanker will
be terrible in the presence of strong nearby signals . I had a couple Orions and the
NB in those where as good as I ever had - BUT any stong sigs within 35-50 khz
would pump the blanker . It was great when everybody thought the band was dead
and I had it to myself for awhile. Otherwise it was useless.

The ability to use NB after the IF roofing is interesting with respect to strong
adjacent sigs BUT apparently the pulses get stretched enough that I have never
seen DSP NB do much good on my noise.

I have wondered about having an option in the K3 to use the sub receiver just as
a noise receiver at someplace out of band where there are no strong signals
(ala one of the old Collins receivers which used about 40 mhz noise receiver
to drive the NB circuitry)

73 Hank K7HP

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