K3S speaker vibration/whine

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K3S speaker vibration/whine

ae4pb
I normally wear a headset but when working I like to listen to code to help
build my proficiency and am hearing a lot of distortion/buzz/whine. I
typically am on 40M running about 500Hz wide (my filter is the 8 pole
400Hz), NR is ON, APF is ON. I've tried changing the tone from 700Hz to down
around 400Hz and the issue just gets worse.

The speaker is tight against the mesh/top cover so I'm not sure why the
sound is so buzzy. I don't notice it on SSB. I end up turning the volume WAY
DOWN which makes it better but still some buzz in there. I plan to wire up
some old surround sound speakers up for stereo and try that but am trying to
figure out what I did wrong in the meantime.

Thanks in advance.

 

 

 

Jerry Moore

CDXA, INDEXA, SKCC, Fists

AE4PB, K3S - S.N. 010324

http://www.qrz.com/db/AE4PB

An Amateur is - Considerate, Loyal, Progressive, Friendly, Balanced, and
Patriotic.

 

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Re: K3S speaker vibration/whine

Randy Moore
Jerry,

I have this buzzing in my K3, and have heard it in some (not all) of the
K3s I have built for friends. I have found that most of it comes from
vibration between the case top and the vertical metal pieces that contact
the top. If that's what you're hearing, you can minimize it by putting some
vinyl tape over the tops of the metal pieces.  In each case I've seen,  the
buzzing is worst around 400 Hz, near my favored CW sidetone frequency!

73,
Randy, KS4L
On Oct 22, 2015 8:32 AM, <[hidden email]> wrote:

> I normally wear a headset but when working I like to listen to code to help
> build my proficiency and am hearing a lot of distortion/buzz/whine. I
> typically am on 40M running about 500Hz wide (my filter is the 8 pole
> 400Hz), NR is ON, APF is ON. I've tried changing the tone from 700Hz to
> down
> around 400Hz and the issue just gets worse.
>
> The speaker is tight against the mesh/top cover so I'm not sure why the
> sound is so buzzy. I don't notice it on SSB. I end up turning the volume
> WAY
> DOWN which makes it better but still some buzz in there. I plan to wire up
> some old surround sound speakers up for stereo and try that but am trying
> to
> figure out what I did wrong in the meantime.
>
> Thanks in advance.
>
>
>
>
>
>
>
> Jerry Moore
>
> CDXA, INDEXA, SKCC, Fists
>
> AE4PB, K3S - S.N. 010324
>
> http://www.qrz.com/db/AE4PB
>
> An Amateur is - Considerate, Loyal, Progressive, Friendly, Balanced, and
> Patriotic.
>
>
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]
>
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Re: K3S speaker vibration/whine

ae4pb
Outstanding!! I’ll try that. I don’t listen to my rig often over the speaker as I have some different hearing losses in each ear.

<snip>

Jerry,

I have this buzzing in my K3, and have heard it in some (not all) of the K3s I have built for friends. I have found that most of it comes from vibration between the case top and the vertical metal pieces that contact the top. If that's what you're hearing, you can minimize it by putting some vinyl tape over the tops of the metal pieces.  In each case I've seen,  the buzzing is worst around 400 Hz, near my favored CW sidetone frequency!

73,

Randy, KS4L

</snip>

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Re: K3S speaker vibration/whine

ae4pb
Yes, I found something about if the speaker frame gets warped it can affect the speaker cone. Maybe I over-tightened the speaker and have it warped. I'll take the cover off, remove the speaker and see what it sounds like without being installed. If that 'fixes" the issue then I'll investigate further. It's a minor thing but something I want to resolve.

Jerry Moore
CDXA, INDEXA, SKCC, Fists
AE4PB, K3S - S.N. 010324
http://www.qrz.com/db/AE4PB
An Amateur is - Considerate, Loyal, Progressive, Friendly, Balanced, and Patriotic.

<snip>
-----Original Message-----
From: Elecraft [mailto:[hidden email]] On Behalf Of Ron D'Eau Claire
Sent: Thursday, October 22, 2015 12:43 PM
To: 'Randy Moore'
Cc: [hidden email]
Subject: Re: [Elecraft] K3S speaker vibration/whine
Are all the top screws in place, including the chassis stiffener bar that is mounted on the KPA3 shield and attaches to the top with three screws?
When assembled, there are no "vertical metal pieces that contact the top" that are not secured by screws.
73, Ron AC7AC
</snip>

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Re: K3S speaker vibration/whine

Victor Rosenthal 4X6GP
In reply to this post by ae4pb
If you do this, be sure to leave some bare metal around the screws so
there can be good electrical contact for shielding purposes.

73,
Vic, 4X6GP/K2VCO
Rehovot, Israel
http://www.qsl.net/k2vco/


On 22 Oct 2015 18:56, [hidden email] wrote:

> Outstanding!! I’ll try that. I don’t listen to my rig often over the
> speaker as I have some different hearing losses in each ear.
>
> <snip>
>
> Jerry,
>
> I have this buzzing in my K3, and have heard it in some (not all) of
> the K3s I have built for friends. I have found that most of it comes
> from vibration between the case top and the vertical metal pieces
> that contact the top. If that's what you're hearing, you can minimize
> it by putting some vinyl tape over the tops of the metal pieces.  In
> each case I've seen,  the buzzing is worst around 400 Hz, near my
> favored CW sidetone frequency!
>
> 73,
>
> Randy, KS4L
>
> </snip>
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Re: K3S speaker vibration/whine

Mike Maloney
I use a 60 degree deflector made from 3" ABS plastic pipe that sits over the stock top mounted speaker.   This gives a noticeable boost to the sidetonefrequency I prefer, 540Hz.   I get nice room filling volume at low settings of the AF gain pot directed toward ear level.   So far this has outperformed anyexternal speaker or headphones I have used for CW.    One of these days should be able to compare to K3S, but I would bet on my deflector first.Never heard any spurious vibration/whine.  
Mike  AC5P   


     On Thursday, October 22, 2015 12:36 PM, Vic Rosenthal 4X6GP/K2VCO <[hidden email]> wrote:
   

 If you do this, be sure to leave some bare metal around the screws so
there can be good electrical contact for shielding purposes.

73,
Vic, 4X6GP/K2VCO
Rehovot, Israel
http://www.qsl.net/k2vco/


On 22 Oct 2015 18:56, [hidden email] wrote:

> Outstanding!! I’ll try that. I don’t listen to my rig often over the
> speaker as I have some different hearing losses in each ear.
>
> <snip>
>
> Jerry,
>
> I have this buzzing in my K3, and have heard it in some (not all) of
> the K3s I have built for friends. I have found that most of it comes
> from vibration between the case top and the vertical metal pieces
> that contact the top. If that's what you're hearing, you can minimize
> it by putting some vinyl tape over the tops of the metal pieces.  In
> each case I've seen,  the buzzing is worst around 400 Hz, near my
> favored CW sidetone frequency!
>
> 73,
>
> Randy, KS4L
>
> </snip>
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Re: K3S speaker vibration/whine

Mike K2MK
In reply to this post by ae4pb
Hi Jerry,

You should also try with APF off. APF on the K3 is useful for pulling out weak signals. I don't see the benefit for general listening.

Just as a further clarification. Generally, if your bandwidth is dialed in as 500Hz then your 400Hz filter has been switched out and your current roofing filter is the next wider one. I say generally because it is possible to set wider cutoff points for the roofing filters.

73,
Mike K2MK

ae4pb wrote
I normally wear a headset but when working I like to listen to code to help
build my proficiency and am hearing a lot of distortion/buzz/whine. I
typically am on 40M running about 500Hz wide (my filter is the 8 pole
400Hz), NR is ON, APF is ON. I've tried changing the tone from 700Hz to down
around 400Hz and the issue just gets worse.

The speaker is tight against the mesh/top cover so I'm not sure why the
sound is so buzzy. I don't notice it on SSB. I end up turning the volume WAY
DOWN which makes it better but still some buzz in there. I plan to wire up
some old surround sound speakers up for stereo and try that but am trying to
figure out what I did wrong in the meantime.

Thanks in advance.
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Re: K3S speaker vibration/whine

ae4pb
In reply to this post by ae4pb
I've not gotten into it yet. My speaker has never been dropped but I'll check.

-----Original Message-----
From: Ron D'Eau Claire [mailto:[hidden email]]
Sent: Thursday, October 22, 2015 3:24 PM
To: [hidden email]; 'Randy Moore'
Cc: [hidden email]
Subject: RE: [Elecraft] K3S speaker vibration/whine

That was my experience too, with an older K2 that uses the same speaker. The magnet is heavy enough to bend the speaker frame if it's handled too roughly. I dropped the top cover with speaker mounted onto a wooden floor.

I confirmed the cause by gently moving the paper speaker cone with my fingers. If the frame is warped you can feel the voice coil rubbing on the magnet. I was able to repair the speaker by putting a blade screwdriver between the frame members and the magnet and twisting it slightly to move the magnet relative to the frame. It involved a bit of trial and error to determine which way the magnet needs to be moved so the voice coil stops rubbing but it's not difficult. That was about 8 years ago. The speaker has been fine ever since.

That was without a shield on the speaker magnet but if you reach in to the magnet (just visible inside the shield) it should work with the shield in place.

73, Ron AC7AC

-----Original Message-----
From: Jerry Moore [mailto:[hidden email]] On Behalf Of [hidden email]
Sent: Thursday, October 22, 2015 10:13 AM
To: 'Ron D'Eau Claire'; 'Randy Moore'
Cc: [hidden email]
Subject: RE: [Elecraft] K3S speaker vibration/whine

Yes, I found something about if the speaker frame gets warped it can affect the speaker cone. Maybe I over-tightened the speaker and have it warped. I'll take the cover off, remove the speaker and see what it sounds like without being installed. If that 'fixes" the issue then I'll investigate further. It's a minor thing but something I want to resolve.

Jerry Moore
CDXA, INDEXA, SKCC, Fists
AE4PB, K3S - S.N. 010324
http://www.qrz.com/db/AE4PB
An Amateur is - Considerate, Loyal, Progressive, Friendly, Balanced, and Patriotic.

<snip>
-----Original Message-----
From: Elecraft [mailto:[hidden email]] On Behalf Of Ron D'Eau Claire
Sent: Thursday, October 22, 2015 12:43 PM
To: 'Randy Moore'
Cc: [hidden email]
Subject: Re: [Elecraft] K3S speaker vibration/whine Are all the top screws in place, including the chassis stiffener bar that is mounted on the KPA3 shield and attaches to the top with three screws?
When assembled, there are no "vertical metal pieces that contact the top" that are not secured by screws.
73, Ron AC7AC
</snip>



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Re: K3S speaker vibration/whine

ae4pb
In reply to this post by Mike K2MK
Will do, I usually operate with headphones and just crank the RF gain down
as needed. That + NR + APF + width really rocks signals down to nearly
nothing unless they are really weak. Then it's a matter of playing with the
settings. I'm finding a need to play with the AGC on some signals where with
others it needs to be engaged more. I'm enjoying the process of learning to
really use it.

Jerry Moore
CDXA, INDEXA, SKCC, Fists
AE4PB, K3S - S.N. 010324
http://www.qrz.com/db/AE4PB
An Amateur is - Considerate, Loyal, Progressive, Friendly, Balanced, and
Patriotic.


-----Original Message-----
From: Elecraft [mailto:[hidden email]] On Behalf Of Mike
K2MK
Sent: Thursday, October 22, 2015 3:06 PM
To: [hidden email]
Subject: Re: [Elecraft] K3S speaker vibration/whine

Hi Jerry,

You should also try with APF off. APF on the K3 is useful for pulling out
weak signals. I don't see the benefit for general listening.

Just as a further clarification. Generally, if your bandwidth is dialed in
as 500Hz then your 400Hz filter has been switched out and your current
roofing filter is the next wider one. I say generally because it is possible
to set wider cutoff points for the roofing filters.

73,
Mike K2MK


ae4pb wrote

> I normally wear a headset but when working I like to listen to code to
> help build my proficiency and am hearing a lot of
> distortion/buzz/whine. I typically am on 40M running about 500Hz wide
> (my filter is the 8 pole 400Hz), NR is ON, APF is ON. I've tried
> changing the tone from 700Hz to down around 400Hz and the issue just
> gets worse.
>
> The speaker is tight against the mesh/top cover so I'm not sure why
> the sound is so buzzy. I don't notice it on SSB. I end up turning the
> volume WAY DOWN which makes it better but still some buzz in there. I
> plan to wire up some old surround sound speakers up for stereo and try
> that but am trying to figure out what I did wrong in the meantime.
>
> Thanks in advance.





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609465.html
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Re: K3S speaker vibration/whine

Randy Moore
In reply to this post by ae4pb
True, Ron, but there are several inches of metal between the screws.

Randy
On Oct 22, 2015 11:43 AM, "Ron D'Eau Claire" <[hidden email]> wrote:

> Are all the top screws in place, including the chassis stiffener bar that
> is mounted on the KPA3 shield and attaches to the top with three screws?
>
> When assembled, there are no "vertical metal pieces that contact the top"
> that are not secured by screws.
>
> 73, Ron AC7AC
>
> -----Original Message-----
> From: Elecraft [mailto:[hidden email]] On Behalf Of
> [hidden email]
> Sent: Thursday, October 22, 2015 8:56 AM
> To: 'Randy Moore'; [hidden email]
> Cc: [hidden email]
> Subject: Re: [Elecraft] K3S speaker vibration/whine
>
> Outstanding!! I’ll try that. I don’t listen to my rig often over the
> speaker as I have some different hearing losses in each ear.
>
> <snip>
>
> Jerry,
>
> I have this buzzing in my K3, and have heard it in some (not all) of the
> K3s I have built for friends. I have found that most of it comes from
> vibration between the case top and the vertical metal pieces that contact
> the top. If that's what you're hearing, you can minimize it by putting some
> vinyl tape over the tops of the metal pieces.  In each case I've seen,  the
> buzzing is worst around 400 Hz, near my favored CW sidetone frequency!
>
> 73,
>
> Randy, KS4L
>
> </snip>
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]
>
>
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Re: K3S speaker vibration/whine

Wes (N7WS)
In reply to this post by Randy Moore
And upset the shielding.

On 10/22/2015 8:07 AM, Randy Moore wrote:
> ...you can minimize it by putting some
> vinyl tape over the tops of the metal pieces.

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Re: K3S speaker vibration/whine

Randy Moore
The tape goes between the screws.

Randy
On Oct 22, 2015 3:31 PM, "Wes (N7WS)" <[hidden email]> wrote:

> And upset the shielding.
>
> On 10/22/2015 8:07 AM, Randy Moore wrote:
>
>> ...you can minimize it by putting some
>> vinyl tape over the tops of the metal pieces.
>>
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
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> Post: mailto:[hidden email]
>
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> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]
>
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Re: K3S speaker vibration/whine

Guy Olinger K2AV
In reply to this post by ae4pb
It is possible to warp a speaker frame by tightening down one mounting
screw all the way before equalizing the torsion on all the screws.
Unfortunately BTDT.

Need to get screws just barely finger tight all around before tightening
further. Even then should be only tightened a half turn at a time, N S E W
order until all are tight. Dropping is very bad.

73, Guy K2AV

On Thursday, October 22, 2015, <[hidden email]> wrote:

> I've not gotten into it yet. My speaker has never been dropped but I'll
> check.
>
> -----Original Message-----
> From: Ron D'Eau Claire [mailto:[hidden email] <javascript:;>]
> Sent: Thursday, October 22, 2015 3:24 PM
> To: [hidden email] <javascript:;>; 'Randy Moore'
> Cc: [hidden email] <javascript:;>
> Subject: RE: [Elecraft] K3S speaker vibration/whine
>
> That was my experience too, with an older K2 that uses the same speaker.
> The magnet is heavy enough to bend the speaker frame if it's handled too
> roughly. I dropped the top cover with speaker mounted onto a wooden floor.
>
> I confirmed the cause by gently moving the paper speaker cone with my
> fingers. If the frame is warped you can feel the voice coil rubbing on the
> magnet. I was able to repair the speaker by putting a blade screwdriver
> between the frame members and the magnet and twisting it slightly to move
> the magnet relative to the frame. It involved a bit of trial and error to
> determine which way the magnet needs to be moved so the voice coil stops
> rubbing but it's not difficult. That was about 8 years ago. The speaker has
> been fine ever since.
>
> That was without a shield on the speaker magnet but if you reach in to the
> magnet (just visible inside the shield) it should work with the shield in
> place.
>
> 73, Ron AC7AC
>
> -----Original Message-----
> From: Jerry Moore [mailto:[hidden email] <javascript:;>] On
> Behalf Of [hidden email] <javascript:;>
> Sent: Thursday, October 22, 2015 10:13 AM
> To: 'Ron D'Eau Claire'; 'Randy Moore'
> Cc: [hidden email] <javascript:;>
> Subject: RE: [Elecraft] K3S speaker vibration/whine
>
> Yes, I found something about if the speaker frame gets warped it can
> affect the speaker cone. Maybe I over-tightened the speaker and have it
> warped. I'll take the cover off, remove the speaker and see what it sounds
> like without being installed. If that 'fixes" the issue then I'll
> investigate further. It's a minor thing but something I want to resolve.
>
> Jerry Moore
> CDXA, INDEXA, SKCC, Fists
> AE4PB, K3S - S.N. 010324
> http://www.qrz.com/db/AE4PB
> An Amateur is - Considerate, Loyal, Progressive, Friendly, Balanced, and
> Patriotic.
>
> <snip>
> -----Original Message-----
> From: Elecraft [mailto:[hidden email] <javascript:;>]
> On Behalf Of Ron D'Eau Claire
> Sent: Thursday, October 22, 2015 12:43 PM
> To: 'Randy Moore'
> Cc: [hidden email] <javascript:;>
> Subject: Re: [Elecraft] K3S speaker vibration/whine Are all the top screws
> in place, including the chassis stiffener bar that is mounted on the KPA3
> shield and attaches to the top with three screws?
> When assembled, there are no "vertical metal pieces that contact the top"
> that are not secured by screws.
> 73, Ron AC7AC
> </snip>
>
>
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email] <javascript:;>
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email] <javascript:;>
>


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