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K3 Tuning encoder pulses and birdie problem

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Jan Erik Holm

K3 Tuning encoder pulses and birdie problem

When 10m opens up this will be a serious problem.

On 28005 KHz a quite strong birdie carrier, on
each side of this carrier there are "tuning pulses
generated from the encoder in the segment 28000 to
28010 KHz. All this gets stronger with Preamp ON.

Is it only my K3? Or is this on all of them?

Any solution?

This internal carrier might be removed with the
new FW but any solution for this tuning puls
problem.

73 Jim SM2EKM

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David Gilbert

Re: K3 Tuning encoder pulses and birdie problem

With my K3 terminated in a dummy load and the preamp off, I can just
barely hear the decoder pulses. I checked it in both CW and SSB, and I
set both modes to 1 KHz bandwidth and adjusted the shift for the same
center frequency of 600 Hz. With the preamp on they are more
noticeable, making the S-meter briefly tick up to about S2 if I tune
quickly. When I stop tuning, of course, the pulses disappear so I'm not
sure they would ever actually hinder me from making a QSO.

Here's an interesting quirk ... possibly just my imagination but I don't
think so. I have the subreceiver installed, and if I engage it so that
I can simultaneously hear the main receiver in my left ear and the
subreceiver in my right ear, tuning the subreceiver across 28005 creates
louder decoder pulses in the main receiver than it does in the
subreceiver. Then again, I have never found as many birdies in the
subreceiver as I have found in the main receiver, and those I've found
in the subreceiver are at least ten db weaker than their main receiver
counterparts.

I do not hear any birdie at that frequency, though. If I listen very,
very hard with the preamp on, I can hear a tone just under the
background noise, but I have to tune the VFO to hear the changing pitch
in order to detect it. Without the preamp on, it is impossible to hear
it at all. It isn't a birdie, though ... the pitch changes smoothly and
slowly as I tune across it. I have found (and removed via SIG RMV) a
few other birdies on 10m, on my rig 28005 isn't one of them.

I do believe that tuning artifacts vary quite a bit from K3 to K3,
though, so you may be experiencing a much greater problem than I am. If
so, you may want to consider making an audio recording of it so that the
rest of us can hear it.

73,
Dave AB7E

Jan Erik Holm wrote:

> When 10m opens up this will be a serious problem.
>
> On 28005 KHz a quite strong birdie carrier, on
> each side of this carrier there are "tuning pulses
> generated from the encoder in the segment 28000 to
> 28010 KHz. All this gets stronger with Preamp ON.
>
> Is it only my K3? Or is this on all of them?
>
> Any solution?
>
> This internal carrier might be removed with the
> new FW but any solution for this tuning puls
> problem.
>
> 73 Jim SM2EKM
>
> ______________________________________________________________
> Elecraft mailing list
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>

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Jan Erik Holm

Re: K3 Tuning encoder pulses and birdie problem

Thanks for the info Dave.

First, I have no sub RX so can´t comment on that.

When checking this I had 50 ohm terminator right at the
SO239 antenna connector. The birdie indicates 2 bars on
the S-meter with preamp ON and no indication with it OFF.

This is subjective of course but with preamp ON those
tuning pulses are quite loud, IMO clearly would be a
problem. Of course with preamp OFF they do get quite
weak however on a frequency like 28 MHz the preamp
will be very much needed.
Now when 10m opens up and we do get some "atmospheric"
noise this tuning pulse deal might not be a problem.
Here in town with antenna connected the tuning pulses
cant be heard due to the high noise floor. However
at my "real" radio station I have very very low noise
floor.
Maybe I am just to picky about things.

Now as I did say before this birdie might be removable
with the 3.03 FW, since 3.03 had some flaws I´m waiting
for an update. Oh I see in your case it didn´t do anything
the the 28005 thing. Yes same pitch change here when
tuning across it, well lets call it a "internal created
carrier" then. More exactly this 28005 thing is more
like 28.0055 MHz in CW REV with normal pitch. Funny
thing is, I put radio in config and in the "ACC REF"
this carrier gets weaker. Guess some ACC REF oscillator,
says it´s at 5.00. Maybe something can be done to it.
I have to read the manual and see what it is.

/ Jim SM2EKM
-----------------
David Gilbert wrote:

>
> With my K3 terminated in a dummy load and the preamp off, I can just
> barely hear the decoder pulses. I checked it in both CW and SSB, and I
> set both modes to 1 KHz bandwidth and adjusted the shift for the same
> center frequency of 600 Hz. With the preamp on they are more
> noticeable, making the S-meter briefly tick up to about S2 if I tune
> quickly. When I stop tuning, of course, the pulses disappear so I'm not
> sure they would ever actually hinder me from making a QSO.
>
> Here's an interesting quirk ... possibly just my imagination but I don't
> think so. I have the subreceiver installed, and if I engage it so that
> I can simultaneously hear the main receiver in my left ear and the
> subreceiver in my right ear, tuning the subreceiver across 28005 creates
> louder decoder pulses in the main receiver than it does in the
> subreceiver. Then again, I have never found as many birdies in the
> subreceiver as I have found in the main receiver, and those I've found
> in the subreceiver are at least ten db weaker than their main receiver
> counterparts.
>
> I do not hear any birdie at that frequency, though. If I listen very,
> very hard with the preamp on, I can hear a tone just under the
> background noise, but I have to tune the VFO to hear the changing pitch
> in order to detect it. Without the preamp on, it is impossible to hear
> it at all. It isn't a birdie, though ... the pitch changes smoothly and
> slowly as I tune across it. I have found (and removed via SIG RMV) a
> few other birdies on 10m, on my rig 28005 isn't one of them.
>
> I do believe that tuning artifacts vary quite a bit from K3 to K3,
> though, so you may be experiencing a much greater problem than I am. If
> so, you may want to consider making an audio recording of it so that the
> rest of us can hear it.
>
> 73,
> Dave AB7E
>
>
>
>
> Jan Erik Holm wrote:
>> When 10m opens up this will be a serious problem.
>>
>> On 28005 KHz a quite strong birdie carrier, on
>> each side of this carrier there are "tuning pulses
>> generated from the encoder in the segment 28000 to
>> 28010 KHz. All this gets stronger with Preamp ON.
>>
>> Is it only my K3? Or is this on all of them?
>>
>> Any solution?
>>
>> This internal carrier might be removed with the
>> new FW but any solution for this tuning puls
>> problem.
>>
>> 73 Jim SM2EKM
>>

Ken Wagner K3IU

Re: K3 Tuning encoder pulses and birdie problem

In reply to this post by Jan Erik Holm

G'morning, Jim:

On my K3 (#202) with latest firmware, I hear only one birdie that
doesn't go away when I disconnect the antenna while tuning between 28000
and 28100. That is a "fast moving" birdie at about 28086. I hear no
"tuning pulses" anyplace.

73,
Ken K3IU
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Jan Erik Holm wrote:

n7ws

Re: K3 Tuning encoder pulses and birdie problem

In reply to this post by Jan Erik Holm

I have to strain to hear the birdie, but the tuning pulses sound like tuning across a radar. These are actually worse with the preamp off, since the added noise with it on masks the pulses to some extent. They are of course, worse with wider bandwidth, since there are more of them to hear at once.

Wes

--- On Wed, 3/25/09, Jan Erik Holm <[hidden email]> wrote:

> From: Jan Erik Holm <[hidden email]>
> Subject: [Elecraft] K3 Tuning encoder pulses and birdie problem
> To: "Elecraft Reflector" <[hidden email]>, "wayne burdick" <[hidden email]>
> Date: Wednesday, March 25, 2009, 12:33 AM
> When 10m opens up this will be a serious problem.
>
> On 28005 KHz a quite strong birdie carrier, on
> each side of this carrier there are "tuning pulses
> generated from the encoder in the segment 28000 to
> 28010 KHz. All this gets stronger with Preamp ON.
>
> Is it only my K3? Or is this on all of them?
>
> Any solution?
>
> This internal carrier might be removed with the
> new FW but any solution for this tuning puls
> problem.
>
> 73 Jim SM2EKM
>
> ______________________________________________________________
> 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

David Gilbert

Re: K3 Tuning encoder pulses and birdie problem

Agreed. I usually operate CW with a pretty narrow bandwidth (200 Hz)
and at first I didn't even hear the pulses on CW. That's why I went
back and set both CW and SSB to the same bandwidth (1000 Hz) to check,
and that made both modes sound the same.

As I said to Jan, the issue may be worse on his rig, but on my K3 the
stuff on 28005 is not a problem even for weak signal work.

73,
Dave AB7E

Wes Stewart wrote:
> They are of course, worse with wider bandwidth, since there are more of them to hear at once.
>
> Wes
>
>
>
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K7TV

Re: K3 Tuning encoder pulses and birdie problem

I can just barely hear the birdie on a dummy load around 28005, but it is so
weak that it is not a problem.

When a real antenna (beam or vertical) is connected, the encoder pulses is
no problem at my rather noisy QTH. At 1kHz bandwidth the S-meter indicates
S3 with AGC on, and the encoder pulses cannot be heard.

On a dummy load, the encoder pulses are very audible at 1 kHz bandwidth.
I have the 500 Hz and 200 Hz filters, currently activated at 550 Hz and 250
Hz (the frequencies closest to the real bandwidths of those filters), which
causes the steps in selectivity to be more significant at those particular
frequencies. That said, when I go from 300 Hz to 250 Hz (the 200 Hz filter
kicks in) the encoder pulses go from very audible to inaudible.
Subjectively, on a dummy load with AGC off, they don't sound louder with
preamp on, maybe because the general noise partly masks them when the preamp
is on. I would describe the sound of the encoder pulses as "running a
fingernail across the teeth of a comb". On the S-meter, with the preamp off,
the pulses are too weak to show up at all. With the preamp on, the pulses
cause the first S-meter segment to flash.

73,
Erik K7TV

----- Original Message -----
From: "David Gilbert" <[hidden email]>
Cc: "Elecraft Reflector" <[hidden email]>
Sent: Wednesday, March 25, 2009 7:43 AM
Subject: Re: [Elecraft] K3 Tuning encoder pulses and birdie problem

>
> Agreed. I usually operate CW with a pretty narrow bandwidth (200 Hz)
> and at first I didn't even hear the pulses on CW. That's why I went
> back and set both CW and SSB to the same bandwidth (1000 Hz) to check,
> and that made both modes sound the same.
>
> As I said to Jan, the issue may be worse on his rig, but on my K3 the
> stuff on 28005 is not a problem even for weak signal work.
>
> 73,
> Dave AB7E
>
>
>
> Wes Stewart wrote:
>> They are of course, worse with wider bandwidth, since there are more of
>> them to hear at once.
>>
>> Wes
>>
>>
>>
> ______________________________________________________________
> Elecraft mailing list
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>

wayne burdick

Re: K3 Tuning encoder pulses and birdie problem

Administrator

Erik N Basilier wrote:

> I can just barely hear the birdie on a dummy load around 28005, but it
> is so
> weak that it is not a problem.
>
> When a real antenna (beam or vertical) is connected, the encoder
> pulses is
> no problem at my rather noisy QTH. At 1kHz bandwidth the S-meter
> indicates
> S3 with AGC on, and the encoder pulses cannot be heard.

If you turn the DSP noise blanker on at a low setting -- say t1-4 -- do
the noise tics get suppressed to a large degree?

tnx
Wayne
N6KR

---

http://www.elecraft.com

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K7TV

Re: K3 Tuning encoder pulses and birdie problem

In reply to this post by Jan Erik Holm

Hearing absolutely nothing from the receiver with the 1-4 NR setting on the
dummy load felt a bit unsettling. I then connected a real antenna and tuned
up the band until I heard a very weak real signal. Not only does the band
noise completely cover up the "encoder ticks" in my location, but also the
band noise as well as the very weak signal do get past the noise reduction,
so that I hear band noise all the time at any frequency with the 1-4 NR
setting active (more noise with the preamp on, as expected), making the rig
sound normal to this non-squelch guy. When I switch to the dummy load, the
radio goes completely quiet even with the preamp on and both gain controls
at maximum. That is OK with me since I don't really want to hear anything on
the dummy antenna anyway.
Next I tried leaving the 1-4 NR active on 20 CW. With the 1 kHz bandwidth
and CW, the this mild NR setting removes so much noise that it is comparable
to reducing the bandwidth to 200 Hz. On 20 SSB this NR setting had little
effect on the voice audio, but it did reduce noise a lot. I used to turn on
NR only when needed, but will try to try leaving it on routinely. I don't
have time for firmware download today but plan to do it fairly soon.

73,
Erik K7TV

----- Original Message -----
From: "Erik N Basilier" <[hidden email]>
To: "Elecraft Reflector" <[hidden email]>
Sent: Wednesday, March 25, 2009 12:35 PM
Subject: Fw: K3 Tuning encoder pulses and birdie problem

>
> ----- Original Message -----
> From: "Erik N Basilier" <[hidden email]>
> To: "wayne burdick" <[hidden email]>
> Sent: Wednesday, March 25, 2009 12:34 PM
> Subject: Re: K3 Tuning encoder pulses and birdie problem
>
>
>> With the DSP NR at F1-4, the encoder tics as well as the normal noise
>> totally disappear, with preamp on or off.
>> F1-3 or lower still has both the tics and normal noise. F2-3 vs F2-4
>> works the same way.
>> I am running 2.76; guess I should update and try again.
>>

Joe Planisky

Re: K3 Tuning encoder pulses and birdie problem

In reply to this post by wayne burdick

Wayne,

I also have the encoder noise around 28005 - 28010. Turning on the NB
at t1-4 does suppress the pulses. Not completely but they're
definitely reduced.

73
--
Joe KB8AP

On Mar 25, 2009, at 12:20 PM, wayne burdick wrote:

>
> If you turn the DSP noise blanker on at a low setting -- say t1-4 --
> do
> the noise tics get suppressed to a large degree?
>
> tnx
> Wayne
> N6KR

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wayne burdick

Re: K3 Tuning encoder pulses and birdie problem

Administrator

Joe Planisky wrote:

> I also have the encoder noise around 28005 - 28010. Turning on the NB
> at t1-4 does suppress the pulses. Not completely but they're
> definitely reduced.

Also try t1-5.

These are very low DSP NB settings. They should have a negligible
effect on normal signals, so you can use this if necessary (i.e., if
you can hear tuning noise even with an antenna connected). Meanwhile,
I'll be looking into the cause.

73,
Wayne
N6KR

---

http://www.elecraft.com

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K7TV

Re: K3 Tuning Encoder Pulses

In reply to this post by K7TV

Re-reading Wayne's suggestion I can see that he meant to try the DSP NB, not
the DSP NR.
I just did so. At t1-4 the tuning pulses were noticeably weaker, but mostly
still there. At t1-7 they were mostly gone but still audible.

Anyway, since I can't even hear the tuning pulses with an antenna connected,
I personally don't need to do anything about them.
However, since I started playing with the NR, I have continued playing with
it for general noise reduction.

In my previous message I forgot to mention the effect of the NR 1-4 on the
general audio level. The reason is I didn't notice any volume decrease on 20
m CW where signals as well as noise were strong. On the other hand, when I
tuned in the very weak carrier on 28060, turning on the NB caused a very
noticeable loss of volume on the wanted signal. With a scope I verified that
the NR F1-4 didn't much affect the volume on the strong CW signals on 20,
while with the weak signal on 10 it made the wanted signal much weaker, and
made the noise weaker still. Yes, the NR definitely improved the S/N ratio
on the weak signal, but overall system gain was only marginal with both
volume controls at maximum. With the strong signals on 20, the NR also
improved S/N but without attenuating the wanted signal. On both bands the
bandwidth was 1 kHz and the AGC F was on (since the NR can't be turned on
unless the AGC is on). AGC PLS ON, AGC SLP 4, AGC THR 7. It looks like the
NR function behaves very differently when the signal level is very low. I
wonder how this relates to the working conditions in the DSP including the
AGC part of it.

73,
Erik K7TV

----- Original Message -----
From: "Erik N Basilier" <[hidden email]>
To: "Elecraft Reflector" <[hidden email]>
Sent: Wednesday, March 25, 2009 1:39 PM
Subject: Re: [Elecraft] K3 Tuning encoder pulses and birdie problem

> Hearing absolutely nothing from the receiver with the 1-4 NR setting on
> the
> dummy load felt a bit unsettling. I then connected a real antenna and
> tuned
> up the band until I heard a very weak real signal. Not only does the band
> noise completely cover up the "encoder ticks" in my location, but also the
> band noise as well as the very weak signal do get past the noise
> reduction,
> so that I hear band noise all the time at any frequency with the 1-4 NR
> setting active (more noise with the preamp on, as expected), making the
> rig
> sound normal to this non-squelch guy. When I switch to the dummy load, the
> radio goes completely quiet even with the preamp on and both gain controls
> at maximum. That is OK with me since I don't really want to hear anything
> on
> the dummy antenna anyway.
> Next I tried leaving the 1-4 NR active on 20 CW. With the 1 kHz bandwidth
> and CW, the this mild NR setting removes so much noise that it is
> comparable
> to reducing the bandwidth to 200 Hz. On 20 SSB this NR setting had little
> effect on the voice audio, but it did reduce noise a lot. I used to turn
> on
> NR only when needed, but will try to try leaving it on routinely. I don't
> have time for firmware download today but plan to do it fairly soon.
>
> 73,
> Erik K7TV

K2QI

Re: K3 Tuning encoder pulses and birdie problem

In reply to this post by wayne burdick

I too have rather strong encoder pulses around 5 MHz. They peak around
S4-S5 with no antenna attached, and preamp off. From prior discussions with
Wayne, the synthesizers seem to be rather "hot".

73,
James K3JPS

On Wed, Mar 25, 2009 at 5:20 PM, wayne burdick <[hidden email]> wrote:

> Joe Planisky wrote:
>
> > I also have the encoder noise around 28005 - 28010. Turning on the NB
> > at t1-4 does suppress the pulses. Not completely but they're
> > definitely reduced.
>
> Also try t1-5.
>
> These are very low DSP NB settings. They should have a negligible
> effect on normal signals, so you can use this if necessary (i.e., if
> you can hear tuning noise even with an antenna connected). Meanwhile,
> I'll be looking into the cause.
>
> 73,
> Wayne
> N6KR
>
> ---
>
> http://www.elecraft.com
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
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>
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> Please help support this email list: http://www.qsl.net/donate.html
>

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