Weird EMI issue... part deux

[K2QI]

OK gang, I don't know what to do at this point and you're my last line of
defense before sending this rig back to Elecraft engineering for analysis.

 

I'll sum it up briefly:

This is rig #2730.  I bought it in kit form, and assembled it myself.

It has a sub receiver, 100w amp, KDVR3, KAT3 tuner, transverter, plus a full
complement of filters on both receivers.

I also have a single general coverage receive module installed on the sub
receiver.

 

This is the problem:

I've noticed that when I'm tuning around 4.8 MHz to 5.3 MHz, I can hear EMI
in the form of a motorboat sound whenever I turn a front panel knob.  It's
most apparent when spinning VFO A or VFO B knobs, but also occurs when
turning the filter knobs.  If I don't touch anything, no noise occurs.  I
can also hear this noise faintly when I'm around 3 MHz.  There is no
front-panel generated noise anywhere else from .5 to 54 MHz other than 3 and
5 MHz.  Also, if I don't have the sub receiver on and I'm only listening to
the main receiver, the EMI noise isn't as loud when the pre-amp is on.  If I
turn the pre-amp off, the EMI generated from spinning knobs increases in
volume.  When I spin a knob and hear this noise, I can also see the S-meter
move in correlation with the noise; spiking at S-7 from time to time.  This
tells me that this is locally generated interference, and occurs somewhere
within the K3's circuitry.  Turning the pre-amp on or off has no effect on
the sub-receiver; the noise is still present.  

 

Here's what I've done:

I've replaced the SUBIN board because I thought it was only the sub-receiver
being affected at one time, but it didn't help. I've also swapped mixers and
synthesizers with no positive result. I've disassembled and reassembled the
entire front panel 4 times already, and cannot find anything wrong.  I've
traced circuits on the sub receiver and SUBIN boards and everything checks
out.  I've also swapped TMP cables around with no improvement. I've also
removed just about every module except the transverter and KAT3 hoping to
eliminate a problem module, but the problem still remains.  I've also
checked every screw and washer throughout the radio, and they all match the
assembly instructions.

 

I'm starting to think that there may be an isolation problem with the main
RF board at this point.  BUT, since I was not able to test the rig without
the KAT3 tuner or removing the transverter board, I cannot be 100% sure.  

Is there anything else I can check before sending the rig back to
Elecraft???

 

Apart from this problem, I have not experienced any other issues with this
radio.  In fact, it works PERFECTLY well.. I should probably tell myself to
live with this noise, but after spending 4k, I don't want too.

 

Suggestions people?  Please help a fellow ham out.

 

73,

James KC2UEE

 

 

 

 

 

 

 

 

 

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[Joe Subich, W4TV-4]

> I've noticed that when I'm tuning around 4.8 MHz to 5.3 MHz,
> I can hear EMI in the form of a motorboat sound whenever I
> turn a front panel knob.  It's most apparent when spinning
> VFO A or VFO B knobs, but also occurs when turning the filter
> knobs.

I have a slight bit of noise when tuning only in that area.
I believe it to be entirely normal.  I recall  Wayne saying
somewhere that the DDS operated in the area of 5 MHz and that
was synthesizer switching noise.  

In my case, the noise is about S1 on an S-meter that was
calibrated to the XG-2 and is in "abs" mode.  In my case
the noise is only audible in the main Rx with VFOA or XIT/RIT
when XIT/RIT is enabled ... or in the sub RX with VFOB or
XIT/RIT when XIT/RIT is enabled.  The noise is masked by
band noise with an antenna connected.  It is audible only
from 4.900 to 5.100 and only noticeable from 4.940 - 5.050
unless one it looking for it.

As you say, it is not present when the VFO or RIT knobs are
at reset ... it is not a problem here.

73,

   ... Joe, W4TV
 
 

> -----Original Message-----
> From: [hidden email]
> [mailto:[hidden email]] On Behalf Of James Sarte
> Sent: Saturday, February 28, 2009 5:27 PM
> To: [hidden email]
> Subject: [Elecraft] Weird EMI issue... part deux
>
>
> OK gang, I don't know what to do at this point and you're my
> last line of defense before sending this rig back to Elecraft
> engineering for analysis.
>
>  
>
> I'll sum it up briefly:
>
> This is rig #2730.  I bought it in kit form, and assembled it myself.
>
> It has a sub receiver, 100w amp, KDVR3, KAT3 tuner,
> transverter, plus a full complement of filters on both receivers.
>
> I also have a single general coverage receive module
> installed on the sub receiver.
>
>  
>
> This is the problem:
>
> I've noticed that when I'm tuning around 4.8 MHz to 5.3 MHz,
> I can hear EMI in the form of a motorboat sound whenever I
> turn a front panel knob.  It's most apparent when spinning
> VFO A or VFO B knobs, but also occurs when turning the filter
> knobs.  If I don't touch anything, no noise occurs.  I can
> also hear this noise faintly when I'm around 3 MHz.  There is
> no front-panel generated noise anywhere else from .5 to 54
> MHz other than 3 and 5 MHz.  Also, if I don't have the sub
> receiver on and I'm only listening to the main receiver, the
> EMI noise isn't as loud when the pre-amp is on.  If I turn
> the pre-amp off, the EMI generated from spinning knobs
> increases in volume.  When I spin a knob and hear this noise,
> I can also see the S-meter move in correlation with the
> noise; spiking at S-7 from time to time.  This tells me that
> this is locally generated interference, and occurs somewhere
> within the K3's circuitry.  Turning the pre-amp on or off has
> no effect on the sub-receiver; the noise is still present.  
>
>  
>
> Here's what I've done:
>
> I've replaced the SUBIN board because I thought it was only
> the sub-receiver being affected at one time, but it didn't
> help. I've also swapped mixers and synthesizers with no
> positive result. I've disassembled and reassembled the entire
> front panel 4 times already, and cannot find anything wrong.  
> I've traced circuits on the sub receiver and SUBIN boards and
> everything checks out.  I've also swapped TMP cables around
> with no improvement. I've also removed just about every
> module except the transverter and KAT3 hoping to eliminate a
> problem module, but the problem still remains.  I've also
> checked every screw and washer throughout the radio, and they
> all match the assembly instructions.
>
>  
>
> I'm starting to think that there may be an isolation problem
> with the main RF board at this point.  BUT, since I was not
> able to test the rig without the KAT3 tuner or removing the
> transverter board, I cannot be 100% sure.  
>
> Is there anything else I can check before sending the rig
> back to Elecraft???
>
>  
>
> Apart from this problem, I have not experienced any other
> issues with this radio.  In fact, it works PERFECTLY well.. I
> should probably tell myself to live with this noise, but
> after spending 4k, I don't want too.
>
>  
>
> Suggestions people?  Please help a fellow ham out.
>
>  
>
> 73,
>
> James KC2UEE
>
>  
>
>  
>
>  
>
>  
>
>  
>
>  
>
>  
>
>  
>
>  
>
> ______________________________________________________________
> 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

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[K2QI]

Hello Joe,

Thanks for the reply.  So if I understand you correctly, this noise is
coming from the synthesizer and is normal?

>From conversations with Elecraft tech support, I got the impression that
this should not be occurring as they could not replicate the noise on their
K3's.

It also does not happen when listening to the sub receiver using the AUX BNC
connector.  It only manifests itself when listening to the main or sub
receivers and using ANT1 or ANT2.

I have noticed that if I come across a broadcast signal within that specific
frequency range, then the signal will mask out the EMI completely, and I
can't hear it until I tune past the station.

It would be helpful if I could get a definite answer from the Elecraft
engineers. So far, I have not heard anything from them.  This noise is
actually quite loud for me, and spikes at S7 on the Elecraft meter.

73,
James KC2UEE


-----Original Message-----
From: Joe Subich, W4TV [mailto:[hidden email]]
Sent: Saturday, February 28, 2009 6:06 PM
To: 'James Sarte'; [hidden email]
Subject: RE: [Elecraft] Weird EMI issue... part deux



> I've noticed that when I'm tuning around 4.8 MHz to 5.3 MHz,
> I can hear EMI in the form of a motorboat sound whenever I
> turn a front panel knob.  It's most apparent when spinning
> VFO A or VFO B knobs, but also occurs when turning the filter
> knobs.

I have a slight bit of noise when tuning only in that area.
I believe it to be entirely normal.  I recall  Wayne saying
somewhere that the DDS operated in the area of 5 MHz and that
was synthesizer switching noise.  

In my case, the noise is about S1 on an S-meter that was
calibrated to the XG-2 and is in "abs" mode.  In my case
the noise is only audible in the main Rx with VFOA or XIT/RIT
when XIT/RIT is enabled ... or in the sub RX with VFOB or
XIT/RIT when XIT/RIT is enabled.  The noise is masked by
band noise with an antenna connected.  It is audible only
from 4.900 to 5.100 and only noticeable from 4.940 - 5.050
unless one it looking for it.

As you say, it is not present when the VFO or RIT knobs are
at reset ... it is not a problem here.

73,

   ... Joe, W4TV
 

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[K2QI]

Hello Gregg,

If these are indeed pulses generated by the encoders, would replacing them
solve the issue, or is this a design problem?

Could this noise be masked out in firmware, or is it a hardware issue that
can't be solved via software?

I do recall hearing about some people having similar problems with their
rigs on 6 meters.  In my case, 6m is quiet with no EMI noise.  

What's troubling me now is that some people say this is normal, while others
like the good folk over at Elecraft tech support cannot replicate this issue
on their K3's.

73,
James KC2UEE


-----Original Message-----
From: Gregg [mailto:[hidden email]]
Sent: Saturday, February 28, 2009 5:55 PM
To: 'James Sarte'
Subject: RE: [Elecraft] Weird EMI issue... part deux

James:

I suspect that what you are hearing is an artifact of the pulses generated
by the tuning encoder. These pulses are audible on some K3s on 6 meters. The
fact that they are not as loud with the pre-amp on is most likely due to an
increase in the noise floor when the pre-amp is activated that somewhat
masks the pulses.

Gregg
W6IZT

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[K2QI]

Hi Gary,

 

Yes, I suppose you're right.  I have however tried rerouting all of the
cables again, and made sure all the TMP connectors were inserted fully.
That unfortunately didn't make any difference.

 

I guess I'll just have to send it back to Elecraft for their engineers to
diagnose.  

 

73,

James KC2UEE

  _____  

From: Gary Hvizdak [mailto:[hidden email]]
Sent: Saturday, February 28, 2009 11:21 PM
To: [hidden email]
Subject: RE: [Elecraft] Weird EMI issue... part deux

 

James,

 

    My guess is that a design problem would affect all K3s.  In your case,
it might be a minor difference in how you've routed the cables.  (Again,
this is just a guess.)

 

73,
Gary  KI4GGX

 

  _____  

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[Steven.Zabarnick]

I was able to reproduce the noise that James is hearing on my #1672 K3. In
my radio it never reaches S7, but I don't have the KBPF3 option. Here, the
RIT and XIT settings do not affect the noise. It is mostly between 4.9 and
5.1 MHz as stated by W4TV.

I never would have noticed this without James' post, and I am not
concerned, but then, I don't have the general receive capability anyway.

Steve N9SZ

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[N2TK]

I had the encoder noise problem on 6M. It happened when I had upgraded the
software (don't remember the version). I reloaded the software and the
problem went away. It has been fine since.
N2TK, Tony

-----Original Message-----
From: [hidden email]
[mailto:[hidden email]] On Behalf Of James Sarte
Sent: Saturday, February 28, 2009 11:37 PM
To: 'Gregg'
Cc: [hidden email]
Subject: Re: [Elecraft] Weird EMI issue... part deux

Hello Gregg,

If these are indeed pulses generated by the encoders, would replacing them
solve the issue, or is this a design problem?

Could this noise be masked out in firmware, or is it a hardware issue that
can't be solved via software?

I do recall hearing about some people having similar problems with their
rigs on 6 meters.  In my case, 6m is quiet with no EMI noise.  

What's troubling me now is that some people say this is normal, while others
like the good folk over at Elecraft tech support cannot replicate this issue
on their K3's.

73,
James KC2UEE


-----Original Message-----
From: Gregg [mailto:[hidden email]]
Sent: Saturday, February 28, 2009 5:55 PM
To: 'James Sarte'
Subject: RE: [Elecraft] Weird EMI issue... part deux

James:

I suspect that what you are hearing is an artifact of the pulses generated
by the tuning encoder. These pulses are audible on some K3s on 6 meters. The
fact that they are not as loud with the pre-amp on is most likely due to an
increase in the noise floor when the pre-amp is activated that somewhat
masks the pulses.

Gregg
W6IZT

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[K2QI]

Hi Tony,

What software are you presently running?  I fortunately never had this VFO
encoder noise at 6m, but it is very noticeable around 5 MHz.

I'm using 2.96 beta.

73,
James KC2UEE

-----Original Message-----
From: N2TK [mailto:[hidden email]]
Sent: Sunday, March 01, 2009 9:13 AM
To: 'James Sarte'; 'Gregg'
Cc: [hidden email]
Subject: RE: [Elecraft] Weird EMI issue... part deux

I had the encoder noise problem on 6M. It happened when I had upgraded the
software (don't remember the version). I reloaded the software and the
problem went away. It has been fine since.
N2TK, Tony


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[K2QI]

Hi Tony,

Interesting... what settings did you have the K3 set too when you did the
test?  Would it be possible for you to try without any antenna connected,
and have the K3 set to AM?  For me, it seems to be loudest on AM mode and
also when the preamp is turned off.  In the absence of any signal entering
the receiver is when this noise is loudest.

I've also tried reloading the software several times, from 2.78 to 2.82 and
now 2.96 and haven't noticed any difference.

If it is encoder pulses or something the synthesizer is doing around 5 MHz,
then why can't other people recreate my problem... or why does it differ
from rig to rig??

73,
James KC2UEE

-----Original Message-----
From: N2TK [mailto:[hidden email]]
Sent: Sunday, March 01, 2009 1:43 PM
To: 'James Sarte'
Subject: RE: [Elecraft] Weird EMI issue... part deux

 
Just checked. No added noise when tuning around 5MHZ.

73,
N2TK/NP2, Tony
#311

-----Original Message-----
From: N2TK [mailto:[hidden email]]
Sent: Sunday, March 01, 2009 1:36 PM
To: 'James Sarte'
Subject: RE: [Elecraft] Weird EMI issue... part deux

Hi James,
Just checked. I am using 2.82. Guess I got behind on the upgrades.
The only thing I do around 5MHZ is 60M and these channels are in memory. So
I would not be tuning around 5MHZ to check for this problem. Will try tuning
around 5 later today and will let you know if I have this problem.

I assume you tried reloading the firmware.

73,
N2TK/NP2, Tony




From: James Sarte [mailto:[hidden email]]
Sent: Sunday, March 01, 2009 1:22 PM
To: 'N2TK'
Cc: [hidden email]
Subject: RE: [Elecraft] Weird EMI issue... part deux





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[N2TK]

I was using SSB settings and had an antenna hooked up. I did not hear any
noise

I put a dummy load on the antenna jack and used AM mode. I can hear noise as
I turn the dial. I can just barely hear the noise when I turn on the preamp.
And with any antenna hooked up I do not hear any noise at all as I turn the
dial.

Jim, do you hear this noise with an antenna hooked up? I do not, so as far
as I am concerned it does not exist. However if you hear this noise when you
have an antenna hooked up you need to talk some more to Elecraft support.

73,
N2TK/NP2, Tony

-----Original Message-----
From: amstel78 [mailto:[hidden email]]
Sent: Sunday, March 01, 2009 8:49 PM
To: 'N2TK'
Cc: [hidden email]
Subject: RE: [Elecraft] Weird EMI issue... part deux

Hi Tony,

Interesting... what settings did you have the K3 set too when you did the
test?  Would it be possible for you to try without any antenna connected,
and have the K3 set to AM?  For me, it seems to be loudest on AM mode and
also when the preamp is turned off.  In the absence of any signal entering
the receiver is when this noise is loudest.

I've also tried reloading the software several times, from 2.78 to 2.82 and
now 2.96 and haven't noticed any difference.

If it is encoder pulses or something the synthesizer is doing around 5 MHz,
then why can't other people recreate my problem... or why does it differ
from rig to rig??

73,
James KC2UEE

-----Original Message-----
From: N2TK [mailto:[hidden email]]
Sent: Sunday, March 01, 2009 1:43 PM
To: 'James Sarte'
Subject: RE: [Elecraft] Weird EMI issue... part deux

 
Just checked. No added noise when tuning around 5MHZ.

73,
N2TK/NP2, Tony
#311

-----Original Message-----
From: N2TK [mailto:[hidden email]]
Sent: Sunday, March 01, 2009 1:36 PM
To: 'James Sarte'
Subject: RE: [Elecraft] Weird EMI issue... part deux

Hi James,
Just checked. I am using 2.82. Guess I got behind on the upgrades.
The only thing I do around 5MHZ is 60M and these channels are in memory. So
I would not be tuning around 5MHZ to check for this problem. Will try tuning
around 5 later today and will let you know if I have this problem.

I assume you tried reloading the firmware.

73,
N2TK/NP2, Tony




From: James Sarte [mailto:[hidden email]]
Sent: Sunday, March 01, 2009 1:22 PM
To: 'N2TK'
Cc: [hidden email]
Subject: RE: [Elecraft] Weird EMI issue... part deux


Hi Tony,

What software are you presently running?  I fortunately never had this VFO
encoder noise at 6m, but it is very noticeable around 5 MHz.

I'm using 2.96 beta.

73,
James KC2UEE

-----Original Message-----
From: N2TK [mailto:[hidden email]]
Sent: Sunday, March 01, 2009 9:13 AM
To: 'James Sarte'; 'Gregg'
Cc: [hidden email]
Subject: RE: [Elecraft] Weird EMI issue... part deux

I had the encoder noise problem on 6M. It happened when I had upgraded the
software (don't remember the version). I reloaded the software and the
problem went away. It has been fine since.
N2TK, Tony




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[K2QI]

Hi Tony,

Thanks for taking the time to do that test for me.

I do hear the noise with an antenna connected, but the antenna is not tuned
for 5MHz so the noise floor is pretty low.  I do not hear this noise through
the sub receiver if I use the AUX BNC connector, but I will hear it through
the sub receiver if it's using the same antenna as the main receiver.

Otherwise, everything else you've described is what I'm experiencing.  This
noise is around an S5 to maybe S7 on the meter when I move the VFO knob.

As you also discovered, turning the preamp on raises the noise floor masking
most of the EMI.  It's not very noticeable when the preamp is on.

Would it be OK to forward this email to Elecraft tech support?  I've been
maintaining a running dialogue with them regarding this issue, and your
findings may help them to develop a solution.

Thanks again and 73,
James KC2UEE



-----Original Message-----
From: N2TK [mailto:[hidden email]]
Sent: Sunday, March 01, 2009 8:32 PM
To: 'amstel78'
Cc: [hidden email]
Subject: RE: [Elecraft] Weird EMI issue... part deux

I was using SSB settings and had an antenna hooked up. I did not hear any
noise

I put a dummy load on the antenna jack and used AM mode. I can hear noise as
I turn the dial. I can just barely hear the noise when I turn on the preamp.
And with any antenna hooked up I do not hear any noise at all as I turn the
dial.

Jim, do you hear this noise with an antenna hooked up? I do not, so as far
as I am concerned it does not exist. However if you hear this noise when you
have an antenna hooked up you need to talk some more to Elecraft support.

73,
N2TK/NP2, Tony

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[N2TK]

James,
I am getting a much lower level of noise than you. With no antenna and the
preamp off, the first bar on the S-meter barely flickers. When I spin the
dial quickly I can get as high as S3 noise. The noise disappears below 4.930
and above 5.110.

I only hear the noise in the main receiver. I can spin the dial on the
sub-receiver, if turned on and also hear the noise in the main receiver.
There is never noise in the sub-receiver. With a dummy load on ANT 1, ANT 2,
AUX and RCV inputs there is noise in the main receiver when spinning the
dial with any antenna port selected.

Once I have an antenna hooked up and the background noise is at least S3 on
that antenna port I can't hear the noise when spinning the dial.


Yes, you can forward this info to whomever you want.

73,
N2TK/NP2, Tony



-----Original Message-----
From: James Sarte [mailto:[hidden email]]
Sent: Sunday, March 01, 2009 10:06 PM
To: 'N2TK'
Cc: [hidden email]
Subject: RE: [Elecraft] Weird EMI issue... part deux

Hi Tony,

Thanks for taking the time to do that test for me.

I do hear the noise with an antenna connected, but the antenna is not tuned
for 5MHz so the noise floor is pretty low.  I do not hear this noise through
the sub receiver if I use the AUX BNC connector, but I will hear it through
the sub receiver if it's using the same antenna as the main receiver.

Otherwise, everything else you've described is what I'm experiencing.  This
noise is around an S5 to maybe S7 on the meter when I move the VFO knob.

As you also discovered, turning the preamp on raises the noise floor masking
most of the EMI.  It's not very noticeable when the preamp is on.

Would it be OK to forward this email to Elecraft tech support?  I've been
maintaining a running dialogue with them regarding this issue, and your
findings may help them to develop a solution.

Thanks again and 73,
James KC2UEE



-----Original Message-----
From: N2TK [mailto:[hidden email]]
Sent: Sunday, March 01, 2009 8:32 PM
To: 'amstel78'
Cc: [hidden email]
Subject: RE: [Elecraft] Weird EMI issue... part deux

I was using SSB settings and had an antenna hooked up. I did not hear any
noise

I put a dummy load on the antenna jack and used AM mode. I can hear noise as
I turn the dial. I can just barely hear the noise when I turn on the preamp.
And with any antenna hooked up I do not hear any noise at all as I turn the
dial.

Jim, do you hear this noise with an antenna hooked up? I do not, so as far
as I am concerned it does not exist. However if you hear this noise when you
have an antenna hooked up you need to talk some more to Elecraft support.

73,
N2TK/NP2, Tony


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[Jan Erik Holm]

I have the same. Also on a number of other places between 0.5 - 30 MHz.
Was there any response from Elecraft on this?

/ SM2EKM
------------
N2TK wrote:

> James,
> I am getting a much lower level of noise than you. With no antenna and the
> preamp off, the first bar on the S-meter barely flickers. When I spin the
> dial quickly I can get as high as S3 noise. The noise disappears below 4.930
> and above 5.110.
>
> I only hear the noise in the main receiver. I can spin the dial on the
> sub-receiver, if turned on and also hear the noise in the main receiver.
> There is never noise in the sub-receiver. With a dummy load on ANT 1, ANT 2,
> AUX and RCV inputs there is noise in the main receiver when spinning the
> dial with any antenna port selected.
>
> Once I have an antenna hooked up and the background noise is at least S3 on
> that antenna port I can't hear the noise when spinning the dial.
>
>
> Yes, you can forward this info to whomever you want.
>
> 73,
> N2TK/NP2, Tony
>
>
>
> -----Original Message-----
> From: James Sarte [mailto:[hidden email]]
> Sent: Sunday, March 01, 2009 10:06 PM
> To: 'N2TK'
> Cc: [hidden email]
> Subject: RE: [Elecraft] Weird EMI issue... part deux
>
> Hi Tony,
>
> Thanks for taking the time to do that test for me.
>
> I do hear the noise with an antenna connected, but the antenna is not tuned
> for 5MHz so the noise floor is pretty low.  I do not hear this noise through
> the sub receiver if I use the AUX BNC connector, but I will hear it through
> the sub receiver if it's using the same antenna as the main receiver.
>
> Otherwise, everything else you've described is what I'm experiencing.  This
> noise is around an S5 to maybe S7 on the meter when I move the VFO knob.
>
> As you also discovered, turning the preamp on raises the noise floor masking
> most of the EMI.  It's not very noticeable when the preamp is on.
>
> Would it be OK to forward this email to Elecraft tech support?  I've been
> maintaining a running dialogue with them regarding this issue, and your
> findings may help them to develop a solution.
>
> Thanks again and 73,
> James KC2UEE
>
>
>
> -----Original Message-----
> From: N2TK [mailto:[hidden email]]
> Sent: Sunday, March 01, 2009 8:32 PM
> To: 'amstel78'
> Cc: [hidden email]
> Subject: RE: [Elecraft] Weird EMI issue... part deux
>
> I was using SSB settings and had an antenna hooked up. I did not hear any
> noise
>
> I put a dummy load on the antenna jack and used AM mode. I can hear noise as
> I turn the dial. I can just barely hear the noise when I turn on the preamp.
> And with any antenna hooked up I do not hear any noise at all as I turn the
> dial.
>
> Jim, do you hear this noise with an antenna hooked up? I do not, so as far
> as I am concerned it does not exist. However if you hear this noise when you
> have an antenna hooked up you need to talk some more to Elecraft support.
>
> 73,
> N2TK/NP2, Tony
>
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
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> Please help support this email list: http://www.qsl.net/donate.html
>

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