[K3] Phase Noise / CW Key Clicks

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[K3] Phase Noise / CW Key Clicks

Matt Zilmer
My case study may not be any less interesting than others you've
heard.  During Field Day, 2011 K3 #24 (mine) was the centerpiece of
our group's CW effort.  The group was a number of aligned clubs, and
we operated 12F (emergency operations center, 12 stations).  You can
imagine the HF overlap involved, since there were nearly always two
stations on one band but on different modes.  Our site was about 350
meters in diameter with stations around the outside edges and a couple
on VHF/UHF in the middle.

Dave, W3DMA, is also a K3 owner.  He and I were partnered on the CW
station.  We operated 19 hours out of the 24 allowed, for about 800
contacts.  This isn't awful, but it should have been better.  The main
cause of our CW count being so low was phase noise from other stations
on the same band at our site.  Many were running > 100W too.  That
WHOOSH Wayne mentioned wiped out a lot of received transmissions on
our end, and we had to constantly ask for AGNs due to a transient high
noise floor.  We could see that 15-20 dB rise of the floor on the P3
quite easily.  The screen went mostly white during those times.

Now - I KNEW better, but I went around to the other stations when they
were operating on same bands as the CW station (Dave at the key, were
at the computer).  They weren't hearing us AT ALL and didn't even know
we were on the same band!  Except for our roving spotter with a
broadband panadapter who could see my K3 but not hear it.  No key
clicks from us, but of course you could hear them all over the band(s)
from remote stations.

Phase noise and key clicks are the enemy.  I respectfully suggest that
Wayne emphasize (as well) that designing a transceiver to
intentionally not produce either of these is a worthy objective more
on a moral plane than an operating advantage.  Tactically, having
clicks and wideband noise could be put to advantage against other FD
groups.  As Wayne pointed out, phase noise may limit receiver
sensitivity (if it's not limited first by other factors), but most
hams have never thought about it that way.  I suspect, in practice,
that in other transceivers phase noise is not the limiting factor in
sensitivity - mainly because the front end design is shoddy compared
to the K3.  Front end noise figure is perhaps a larger factor in many
cases.

The main real-world problem is that the K3 is a minority in the
general ham rig population.  Maybe someday, the K3 penetration rate
will be high enough that we can hear it in how quiet the bands are.
Crowded but quiet between signals that is.
   
73,
Matt Zilmer, W6NIA / NNN0UET / NNN0GAF THREE
NMCM RMS Winmor: NNU9ET-5: Upland, CA.
NAQCC: 6081, 10-10: 10413, KX3 #6/FT

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Re: [K3] Phase Noise / CW Key Clicks

Chip Stratton
Very interesting. I was operating at our local submarine for Museum Ships
Day, using my K2 in the field about 200 yards away from the sub from which
they were operating SSB on 20 meters. I tried to operate 20m CW but the
"whooshing" on the band anywhere in the CW segment was just too much. I
thought it was just blow-by of the K2's xtal filters, but I think now I'm
learning it was the dirty transmitter they were using - not sure which one.

Chip
AE5KA

On Thu, Sep 13, 2012 at 12:18 AM, Matt Zilmer <[hidden email]> wrote:

> My case study may not be any less interesting than others you've
> heard.  During Field Day, 2011 K3 #24 (mine) was the centerpiece of
> our group's CW effort.  The group was a number of aligned clubs, and
> we operated 12F (emergency operations center, 12 stations).  You can
> imagine the HF overlap involved, since there were nearly always two
> stations on one band but on different modes.  Our site was about 350
> meters in diameter with stations around the outside edges and a couple
> on VHF/UHF in the middle.
>
> Dave, W3DMA, is also a K3 owner.  He and I were partnered on the CW
> station.  We operated 19 hours out of the 24 allowed, for about 800
> contacts.  This isn't awful, but it should have been better.  The main
> cause of our CW count being so low was phase noise from other stations
> on the same band at our site.  Many were running > 100W too.  That
> WHOOSH Wayne mentioned wiped out a lot of received transmissions on
> our end, and we had to constantly ask for AGNs due to a transient high
> noise floor.  We could see that 15-20 dB rise of the floor on the P3
> quite easily.  The screen went mostly white during those times.
>
> Now - I KNEW better, but I went around to the other stations when they
> were operating on same bands as the CW station (Dave at the key, were
> at the computer).  They weren't hearing us AT ALL and didn't even know
> we were on the same band!  Except for our roving spotter with a
> broadband panadapter who could see my K3 but not hear it.  No key
> clicks from us, but of course you could hear them all over the band(s)
> from remote stations.
>
> Phase noise and key clicks are the enemy.  I respectfully suggest that
> Wayne emphasize (as well) that designing a transceiver to
> intentionally not produce either of these is a worthy objective more
> on a moral plane than an operating advantage.  Tactically, having
> clicks and wideband noise could be put to advantage against other FD
> groups.  As Wayne pointed out, phase noise may limit receiver
> sensitivity (if it's not limited first by other factors), but most
> hams have never thought about it that way.  I suspect, in practice,
> that in other transceivers phase noise is not the limiting factor in
> sensitivity - mainly because the front end design is shoddy compared
> to the K3.  Front end noise figure is perhaps a larger factor in many
> cases.
>
> The main real-world problem is that the K3 is a minority in the
> general ham rig population.  Maybe someday, the K3 penetration rate
> will be high enough that we can hear it in how quiet the bands are.
> Crowded but quiet between signals that is.
>
> 73,
> Matt Zilmer, W6NIA / NNN0UET / NNN0GAF THREE
> NMCM RMS Winmor: NNU9ET-5: Upland, CA.
> NAQCC: 6081, 10-10: 10413, KX3 #6/FT
>
> ______________________________________________________________
> 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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Re: [K3] Phase Noise / CW Key Clicks

Matt Zilmer
Might be both.

matt

On Thu, 13 Sep 2012 08:41:20 -0400, you wrote:

>Very interesting. I was operating at our local submarine for Museum Ships
>Day, using my K2 in the field about 200 yards away from the sub from which
>they were operating SSB on 20 meters. I tried to operate 20m CW but the
>"whooshing" on the band anywhere in the CW segment was just too much. I
>thought it was just blow-by of the K2's xtal filters, but I think now I'm
>learning it was the dirty transmitter they were using - not sure which one.
>
>Chip
>AE5KA
>
>On Thu, Sep 13, 2012 at 12:18 AM, Matt Zilmer <[hidden email]> wrote:
>
>> My case study may not be any less interesting than others you've
>> heard.  During Field Day, 2011 K3 #24 (mine) was the centerpiece of
>> our group's CW effort.  The group was a number of aligned clubs, and
>> we operated 12F (emergency operations center, 12 stations).  You can
>> imagine the HF overlap involved, since there were nearly always two
>> stations on one band but on different modes.  Our site was about 350
>> meters in diameter with stations around the outside edges and a couple
>> on VHF/UHF in the middle.
>>
>> Dave, W3DMA, is also a K3 owner.  He and I were partnered on the CW
>> station.  We operated 19 hours out of the 24 allowed, for about 800
>> contacts.  This isn't awful, but it should have been better.  The main
>> cause of our CW count being so low was phase noise from other stations
>> on the same band at our site.  Many were running > 100W too.  That
>> WHOOSH Wayne mentioned wiped out a lot of received transmissions on
>> our end, and we had to constantly ask for AGNs due to a transient high
>> noise floor.  We could see that 15-20 dB rise of the floor on the P3
>> quite easily.  The screen went mostly white during those times.
>>
>> Now - I KNEW better, but I went around to the other stations when they
>> were operating on same bands as the CW station (Dave at the key, were
>> at the computer).  They weren't hearing us AT ALL and didn't even know
>> we were on the same band!  Except for our roving spotter with a
>> broadband panadapter who could see my K3 but not hear it.  No key
>> clicks from us, but of course you could hear them all over the band(s)
>> from remote stations.
>>
>> Phase noise and key clicks are the enemy.  I respectfully suggest that
>> Wayne emphasize (as well) that designing a transceiver to
>> intentionally not produce either of these is a worthy objective more
>> on a moral plane than an operating advantage.  Tactically, having
>> clicks and wideband noise could be put to advantage against other FD
>> groups.  As Wayne pointed out, phase noise may limit receiver
>> sensitivity (if it's not limited first by other factors), but most
>> hams have never thought about it that way.  I suspect, in practice,
>> that in other transceivers phase noise is not the limiting factor in
>> sensitivity - mainly because the front end design is shoddy compared
>> to the K3.  Front end noise figure is perhaps a larger factor in many
>> cases.
>>
>> The main real-world problem is that the K3 is a minority in the
>> general ham rig population.  Maybe someday, the K3 penetration rate
>> will be high enough that we can hear it in how quiet the bands are.
>> Crowded but quiet between signals that is.
>>
>> 73,
>> Matt Zilmer, W6NIA / NNN0UET / NNN0GAF THREE
>> NMCM RMS Winmor: NNU9ET-5: Upland, CA.
>> NAQCC: 6081, 10-10: 10413, KX3 #6/FT
>>
>> ______________________________________________________________
>> 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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>
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Re: [K3] Phase Noise / CW Key Clicks

Geoffrey Mackenzie-Kennedy-3
In reply to this post by Matt Zilmer
Hello Matt,

Interesting that the other stations whose phase noise pestered you, did not
sense the presence of the K3's strong signal as the result of reciprocal
mixing in their receivers.  Can you recall the model or models of
transceiver the others were using?

73,
Geoff
LX2AO


On September 13, 2012 at 6:18 AM, Matt Zilmer wrote:


<snip>

> Now - I KNEW better, but I went around to the other stations when they
> were operating on same bands as the CW station (Dave at the key, were
> at the computer).  They weren't hearing us AT ALL and didn't even know
> we were on the same band!  Except for our roving spotter with a
> broadband panadapter who could see my K3 but not hear it.  No key
> clicks from us, but of course you could hear them all over the band(s)
> from remote stations.

<snip>

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Re: [K3] Phase Noise / CW Key Clicks

Ethan Miller K8GU
I also had this problem recently:  I was using my K3 in the vicinity
of several other operators who were using an IC-706MkIIG, an FT-857D,
and an IC-7000.  All of these other radios produced horrible in-band
phase noise.  When I asked them about it, they were completely unaware
that I was on the band!

The other stations were at least 100 meters away and using opposite
polarization from me on 20 meters.  The noise floor increased from S0
to S3-S4 with the 706 and 857, which were farther away and S0 to S7ish
with the 7000 which was much closer.

Of course, this was one of the many selling points of the K3 for me.
I guess the K2 is also very clean on TX phase noise?

73,

--Ethan, K8GU/4.

On Thu, Sep 13, 2012 at 11:00 AM, Geoffrey Mackenzie-Kennedy
<[hidden email]> wrote:

> Hello Matt,
>
> Interesting that the other stations whose phase noise pestered you, did not
> sense the presence of the K3's strong signal as the result of reciprocal
> mixing in their receivers.  Can you recall the model or models of
> transceiver the others were using?
>
> 73,
> Geoff
> LX2AO
>
>
> On September 13, 2012 at 6:18 AM, Matt Zilmer wrote:
>
>
> <snip>
>
>> Now - I KNEW better, but I went around to the other stations when they
>> were operating on same bands as the CW station (Dave at the key, were
>> at the computer).  They weren't hearing us AT ALL and didn't even know
>> we were on the same band!  Except for our roving spotter with a
>> broadband panadapter who could see my K3 but not hear it.  No key
>> clicks from us, but of course you could hear them all over the band(s)
>> from remote stations.
>
> <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



--
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Repair.  Re-use.  Re-purpose.  Recycle.
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Re: [K3] Phase Noise / CW Key Clicks

Alan Bloom
> I was using my K3 in the vicinity
> of several other operators who were using an IC-706MkIIG, an FT-857D,
> and an IC-7000.  All of these other radios produced horrible in-band
> phase noise.  When I asked them about it, they were completely unaware
> that I was on the band!

Assuming the same synthesizer is used for the transmitter and receiver,
then phase noise should affect the receiver and transmitter equally.
Those guys using transceivers with poor phase noise should also have
been wiped out on receive, even though the interfering K3 was clean.

I suspect the problem is broadband amplitude noise generated in the
power amplifier chain.  That would affect the transmitted noise but not
the receiver performance.

Alan N1AL


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Re: [K3] Phase Noise / CW Key Clicks

Ethan Miller K8GU
Interesting point---thanks for clarifying that, Alan.

At any rate, these other rigs were dirty and operating with them was a nuisance.

73,

--Ethan, K8GU/4.

On Thu, Sep 13, 2012 at 1:07 PM, Alan Bloom <[hidden email]> wrote:

>> I was using my K3 in the vicinity
>> of several other operators who were using an IC-706MkIIG, an FT-857D,
>> and an IC-7000.  All of these other radios produced horrible in-band
>> phase noise.  When I asked them about it, they were completely unaware
>> that I was on the band!
>
> Assuming the same synthesizer is used for the transmitter and receiver,
> then phase noise should affect the receiver and transmitter equally.
> Those guys using transceivers with poor phase noise should also have
> been wiped out on receive, even though the interfering K3 was clean.
>
> I suspect the problem is broadband amplitude noise generated in the
> power amplifier chain.  That would affect the transmitted noise but not
> the receiver performance.
>
> Alan N1AL
>
>



--
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Repair.  Re-use.  Re-purpose.  Recycle.
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Re: [K3] Phase Noise / CW Key Clicks

Bill W4ZV
In reply to this post by Matt Zilmer
Matt Zilmer wrote
Phase noise and key clicks are the enemy.  I respectfully suggest that
Wayne emphasize (as well) that designing a transceiver to
intentionally not produce either of these is a worthy objective more
on a moral plane than an operating advantage.  Tactically, having
clicks and wideband noise could be put to advantage against other FD
groups.  
Regarding your last sentence, to my knowledge, Elecraft is the ONLY manufacturer who does not allow adjustment of CW Rise/Fall time (Ten-Tec, Yaesu and possibly others do).  Adjusting this time to less than ~5ms can cause clicks which, as you said above, can be useful in contests to keep others away from your run frequency.  

Kudos to Wayne for not allowing the user to adjust this parameter and therefore keeping our K3s cleaner than other rigs.

73,  Bill  W4ZV
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Re: [K3] Phase Noise / CW Key Clicks

mzilmer
Yep, I was finding merit in this choice of action.  Allowing the adjustment of rise/fall timings  into key click territory should be discouraged.  

Matt Zilmer
Consultant - Product Management Dept.
Magellan Navigation / MiTAC Digital Corp.
Tel: (909) 394-6052
Cell: (909) 730-6552
In status quo voluntas non sufficit

-----Original Message-----
From: [hidden email] [mailto:[hidden email]] On Behalf Of Bill W4ZV
Sent: Thursday, September 13, 2012 11:21 AM
To: [hidden email]
Subject: Re: [Elecraft] [K3] Phase Noise / CW Key Clicks


Matt Zilmer wrote
>
> Phase noise and key clicks are the enemy.  I respectfully suggest that
> Wayne emphasize (as well) that designing a transceiver to
> intentionally not produce either of these is a worthy objective more
> on a moral plane than an operating advantage.  Tactically, having
> clicks and wideband noise could be put to advantage against other FD
> groups.
>

Regarding your last sentence, to my knowledge, Elecraft is the ONLY manufacturer who does not allow adjustment of CW Rise/Fall time (Ten-Tec, Yaesu and possibly others do).  Adjusting this time to less than ~5ms can cause clicks which, as you said above, can be useful in contests to keep others away from your run frequency.  

Kudos to Wayne for not allowing the user to adjust this parameter and therefore keeping our K3s cleaner than other rigs.

73,  Bill  W4ZV




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Re: [K3] Phase Noise / CW Key Clicks

Jim Brown-10
In reply to this post by Matt Zilmer
On 9/12/2012 9:18 PM, Matt Zilmer wrote:
> The main real-world problem is that the K3 is a minority in the
> general ham rig population.  Maybe someday, the K3 penetration rate
> will be high enough that we can hear it in how quiet the bands are.
> Crowded but quiet between signals that is.

Yes, BUT -- considering the number of active contesters in the world
(study the results of major contests), I'd say that Elecraft has been
achieving pretty good penetration. If I'm not mistaken, I've seen serial
numbers in the 7,000 range, and we know that they started at #1 and
didn't skip any. It's also gotten to the point where experienced
DXpeditioners would rather drag their own K3s through airports than
accept freebies from Icom or Yaesu.

More important, it's REAL easy to see the difference between a clean rig
and a dirty one on a P3, and every season I see a greater proportion of
clean ones!  It's gotten to the point that, at least here on the West
Coast, a dirty signal stands out like a sore thumb!

73, Jim K9YC
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Re: [K3] Phase Noise / CW Key Clicks

Gary Bartlett VE1RGB
In reply to this post by Ethan Miller K8GU

And thanks from me too.  What has been pointed out here and what Lyle said
yesterday (see below) and what others have pointed out in their own ways has
demystified a subject that, once couched in simple words, is not so hard to
understand.

Quote from Lyle KK7P:  Transmitted broadband noise is often much higher than
phase noise from the various oscillators.  In general, I'd expect the
transmitter broadband noise to be higher, perhaps much higher, than the
phase noise contribution from the oscillators.  The noise contribution from
low level transmit buffers, for example, can be significant. Unquote.

Thanks, guys.

73,
Gary VE1RGB



-----Original Message-----
From: [hidden email]
[mailto:[hidden email]] On Behalf Of Ethan Miller K8GU
Sent: September 13, 2012 2:48 PM
To: [hidden email]
Subject: Re: [Elecraft] [K3] Phase Noise / CW Key Clicks

Interesting point---thanks for clarifying that, Alan.


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Re: [K3] Phase Noise / CW Key Clicks

Rick Tavan N6XI
In reply to this post by Matt Zilmer
Although the dominant competitive specs these days are receiver measurements, the cleanliness of the K3 should get more press. It is perhaps a tough moral sell but drop-dead easy in the multi-TX market. And Field Day is the most popular activity in US ham radio. In addition to enhancing K3 sales, more awareness should also stimulate Elecraft's competition, perhaps some day making a big improvement in inter-station interference everywhere.

There may even be a viable argument that Elecraft has advanced the state of the art enough that eventual tightening of regulatory spectral purity standards for new rigs will be merited. Some may balk at that, but note that we are no longer allowed to operate spark, much to everyone's satisfaction.

Rick

--
Rick Tavan N6XI

On Sep 12, 2012, at 9:18 PM, Matt Zilmer <[hidden email]> wrote:

>
>
> Phase noise and key clicks are the enemy.  I respectfully suggest that
> Wayne emphasize (as well) that designing a transceiver to
> intentionally not produce either of these is a worthy objective more
> on a moral plane than an operating advantage.  Tactically, having
> clicks and wideband noise could be put to advantage against other FD
> groups.  As Wayne pointed out, phase noise may limit receiver
> sensitivity (if it's not limited first by other factors), but most
> hams have never thought about it that way.  I suspect, in practice,
> that in other transceivers phase noise is not the limiting factor in
> sensitivity - mainly because the front end design is shoddy compared
> to the K3.  Front end noise figure is perhaps a larger factor in many
> cases.
>
> The main real-world problem is that the K3 is a minority in the
> general ham rig population.  Maybe someday, the K3 penetration rate
> will be high enough that we can hear it in how quiet the bands are.
> Crowded but quiet between signals that is.
>
>
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Re: [K3] Phase Noise / CW Key Clicks

Nate Bargmann
* On 2012 13 Sep 14:25 -0500, Rick Tavan wrote:
> Although the dominant competitive specs these days are receiver
> measurements, the cleanliness of the K3 should get more press. It is
> perhaps a tough moral sell but drop-dead easy in the multi-TX market.
> And Field Day is the most popular activity in US ham radio. In
> addition to enhancing K3 sales, more awareness should also stimulate
> Elecraft's competition, perhaps some day making a big improvement in
> inter-station interference everywhere.

And still, there are claims leveled at the K3 in other forums about
"poor transmit IMD".  I'm not sure what this means in the context of
transmitted broad band and phase noise.

> There may even be a viable argument that Elecraft has advanced the
> state of the art enough that eventual tightening of regulatory
> spectral purity standards for new rigs will be merited. Some may balk
> at that, but note that we are no longer allowed to operate spark, much
> to everyone's satisfaction.

There is much evidence given by operators that the K3 is a very clean
transmitter.  How can we argue against the claims of poor transmit IMD
and what does that actually mean to our spectrum neighbors on the air?

73, de Nate, N0NB >>

--

"The optimist proclaims that we live in the best of all
possible worlds.  The pessimist fears this is true."

Ham radio, Linux, bikes, and more: http://www.n0nb.us
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Re: [K3] Phase Noise / CW Key Clicks

ab2tc
In reply to this post by Alan Bloom
Hi,

Agreed on both points. Others have pointed out that wideband noise on transmit is often much higher than the phase noise produced by the synthesizer. My neighbor (3 doors = 240' away) is a good example of noise produced by the transmit amplifiers rather than the synthesizer. He uses mostly CW and his IC-756 has strong wideband noise even with key up (I am sure he does nut run full QSK). The key up noise must be produced by his amplifier chain, not the synth. It of course also completely rules out noise from my synthesizer as the cause.

AB2TC - Knut

Alan Bloom wrote
<snip>
Assuming the same synthesizer is used for the transmitter and receiver,
then phase noise should affect the receiver and transmitter equally.
Those guys using transceivers with poor phase noise should also have
been wiped out on receive, even though the interfering K3 was clean.

I suspect the problem is broadband amplitude noise generated in the
power amplifier chain.  That would affect the transmitted noise but not
the receiver performance.

Alan N1AL


<snip again>
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Re: [K3] Phase Noise / CW Key Clicks

Joe Subich, W4TV-4
In reply to this post by Gary Bartlett VE1RGB

> What has been pointed out here and what Lyle said yesterday (see
> below) and what others have pointed out in their own ways has
> demystified a subject that, once couched in simple words, is not so
> hard to understand.

Put another way, so many of the offending transceivers run the transmit
IF "wide open" to insure sufficient drive to the final amplifiers and
rely on ALC feedback to reduce the gain as necessary.  This assures
that the phase noise from multiple synthesizers and low level noise in
the amplifiers themselves will *all* appear in the output as much as
20 dB higher than a rig like the K3 where the IF gain is properly
controlled.

73,

    ... Joe, W4TV


On 9/13/2012 2:53 PM, gary bartlett wrote:

>
> And thanks from me too.  What has been pointed out here and what Lyle said
> yesterday (see below) and what others have pointed out in their own ways has
> demystified a subject that, once couched in simple words, is not so hard to
> understand.
>
> Quote from Lyle KK7P:  Transmitted broadband noise is often much higher than
> phase noise from the various oscillators.  In general, I'd expect the
> transmitter broadband noise to be higher, perhaps much higher, than the
> phase noise contribution from the oscillators.  The noise contribution from
> low level transmit buffers, for example, can be significant. Unquote.
>
> Thanks, guys.
>
> 73,
> Gary VE1RGB
>
>
>
> -----Original Message-----
> From: [hidden email]
> [mailto:[hidden email]] On Behalf Of Ethan Miller K8GU
> Sent: September 13, 2012 2:48 PM
> To: [hidden email]
> Subject: Re: [Elecraft] [K3] Phase Noise / CW Key Clicks
>
> Interesting point---thanks for clarifying that, Alan.
>
>
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Re: [K3] Phase Noise / CW Key Clicks

Guy, K2AV
In reply to this post by Bill W4ZV
Us old f*rts have got to quit thinking analog.

K3 CW is not keyed. It's effectively data-graphed and fed directly
into a digital-analog converter (DAC).  Remember, ZERO SIGNAL OUT in
TX state is A STREAM OF DATA VALUES sent to a DAC that is RUNNING, not
a stage that is switched off. The "keying circuit" is a subroutine.
Paddle dash dot and Key In are read as a binary state on three lines
to a CPU that go low when input is grounded. Shows up as a value in a
register.

There may be a bit more (or less depending on your point of view) to
the "lack of choice" than it seems.  When I look in the schematic for
TX RX switching, all I see is unshaped on/off diode circuits all over
the place that are switching from a common line or two, transiting the
K3 circuits from TX state to RX state. You cannot follow the key line
to an analog circuit that is turning an oscillator on and off, or
breaking the feed of a steady oscillator to a following stage.  So
there is no capacitor to discharge for shaping the CW waveform, no
resistor to adjust.  This is not at all like my FT1000MP, where very
loosely controlled cap values made some MP's clicks far worse than
others.

The K3 lets the RX to TX state change complete before it feeds the DAC
any data that implies signal power output.

Turning on the CW baud consists of some subroutine feeding some other
subroutine numbers that are sent to the DAC, AFTER the K3 has gone RX
state to TX state. Reverse for RX to TX. On the straight key side of
15 kHz TX IF, it's nuthin but arithmetic. The shape of the CW baud
rise and fall transitions is a pile of numbers. It is oh so possible
to monkey with the numbers to get a clear baud transition that has no
artifacts in the adjacent channel once transmitted. And a baud
transition, by the way, that is impossible with any analog component
switch.  Having a "choice" of keying waveshapes means that there has
to be alternate piles of numbers or subroutines, and the extra running
code to switch them.  Why bother.  They made it the cleanest CW signal
on the band and went to work on something else.

73, Guy.


On Thu, Sep 13, 2012 at 2:21 PM, Bill W4ZV <[hidden email]> wrote:

>
> Matt Zilmer wrote
>>
>> Phase noise and key clicks are the enemy.  I respectfully suggest that
>> Wayne emphasize (as well) that designing a transceiver to
>> intentionally not produce either of these is a worthy objective more
>> on a moral plane than an operating advantage.  Tactically, having
>> clicks and wideband noise could be put to advantage against other FD
>> groups.
>>
>
> Regarding your last sentence, to my knowledge, Elecraft is the ONLY
> manufacturer who does not allow adjustment of CW Rise/Fall time (Ten-Tec,
> Yaesu and possibly others do).  Adjusting this time to less than ~5ms can
> cause clicks which, as you said above, can be useful in contests to keep
> others away from your run frequency.
>
> Kudos to Wayne for not allowing the user to adjust this parameter and
> therefore keeping our K3s cleaner than other rigs.
>
> 73,  Bill  W4ZV
>
>
>
>
> --
> View this message in context: http://elecraft.365791.n2.nabble.com/K3-Phase-Noise-CW-Key-Clicks-tp7562575p7562615.html
> Sent from the Elecraft mailing list archive at Nabble.com.
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Re: [K3] Phase Noise / CW Key Clicks

alorona
I once spoke to a nationally-known, "Big Gun" contester who felt that the phase
noise and key click sidebands generated by hisĀ station were an asset because
they cleared a "guard band" around his signal since other stations had to stay
away. He felt no motivation at all to clean up his signal. I don't know how many
other big guns share this philosophy but my acquaintance can't be the only one.

AlĀ  W6LX
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Re: [K3] Phase Noise / CW Key Clicks

Don Wilhelm-4
There will always be "alligators" - big mouth, small ears.

73,
Don W3FPR

On 9/13/2012 7:00 PM, Al Lorona wrote:
> I once spoke to a nationally-known, "Big Gun" contester who felt that the phase
> noise and key click sidebands generated by his station were an asset because
> they cleared a "guard band" around his signal since other stations had to stay
> away. He felt no motivation at all to clean up his signal. I don't know how many
> other big guns share this philosophy but my acquaintance can't be the only one.
>
>

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Re: [K3] Phase Noise / CW Key Clicks

Bruce Beford-2
In reply to this post by Matt Zilmer
Sadly, Al- I believe quite a few "Big Guns" that enjoy reading their calls
in the contest reports feel exactly this way. To them it would be
detrimental to clean up their signals. They have no incentive at all to
care.

73,
Bruce, N1RX

> I once spoke to a nationally-known, "Big Gun" contester who felt that the
> phase noise and key click sidebands generated by his station were an asset
> because they cleared a "guard band" around his signal since other stations
> had to stay away. He felt no motivation at all to clean up his signal. I
> don't know how many other big guns share this philosophy but my
> acquaintance can't be the only one.

> Al  W6LX



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Re: [K3] Phase Noise / CW Key Clicks

Rick WA6NHC
In reply to this post by Don Wilhelm-4
And peanut sized brains like most other dinosaurs...

Not quite extinct yet it seems.

Rick wa6nhc/kl

-----Original Message-----
From: Don Wilhelm

There will always be "alligators" - big mouth, small ears.

73,
Don W3FPR

On 9/13/2012 7:00 PM, Al Lorona wrote:
> I once spoke to a nationally-known, "Big Gun" contester who felt that the
phase
> noise and key click sidebands generated by his station were an asset
because
> they cleared a "guard band" around his signal since other stations had to
stay
> away. He felt no motivation at all to clean up his signal. I don't know
how many
> other big guns share this philosophy but my acquaintance can't be the only
one.

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1234