K3 "blur" was a no-show during ARRL 10m

classic Classic list List threaded Threaded
11 messages Options
Reply | Threaded
Open this post in threaded view
|

K3 "blur" was a no-show during ARRL 10m

David Gilbert

Well, I recorded most of my time in the ARRL 10m contest this past
weekend but I didn't save it.  I only had three or four situations where
I thought possibly I was hearing some blurring of signals but they
weren't definitive at all, and in those cases the signals were virtually
zero beat so I chalked it up to that instead.  I was fairly seriously
operating the contest (about 1,000 CW contacts) and running a frequency
most of the time so I didn't go looking for other examples, and I was
running low power so I rarely had more than three callers at a time.

I was all primed to adjust RF Gain and manually switch roofing filters
if the effect occurred, but it didn't for me this time.  Sorry I
couldn't come up with an example.

Anyone else capture anything?

73,
Dave   AB7E




______________________________________________________________
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
Reply | Threaded
Open this post in threaded view
|

Re: K3 "blur" was a no-show during ARRL 10m

Lu Romero - W4LT
I have sent my recording in already.  I heard some in my CW
pileups. Some were zero beat issues but not all.  

-lu-W4LT-

====================


Message: 6
Date: Mon, 12 Dec 2011 10:43:04 -0700
From: David Gilbert <[hidden email]>
Subject: [Elecraft] K3 "blur" was a no-show during ARRL 10m
To: Elecraft Reflector <[hidden email]>
Message-ID: <[hidden email]>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed


Well, I recorded most of my time in the ARRL 10m contest
this past
weekend but I didn't save it.  I only had three or four
situations where
I thought possibly I was hearing some blurring of signals
but they
weren't definitive at all, and in those cases the signals
were virtually
zero beat so I chalked it up to that instead.  I was fairly
seriously
operating the contest (about 1,000 CW contacts) and running
a frequency
most of the time so I didn't go looking for other examples,
and I was
running low power so I rarely had more than three callers at
a time.

I was all primed to adjust RF Gain and manually switch
roofing filters
if the effect occurred, but it didn't for me this time.
Sorry I
couldn't come up with an example.

Anyone else capture anything?

73,
Dave   AB7E






______________________________________________________________
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
Reply | Threaded
Open this post in threaded view
|

Re: K3 "blur" was a no-show during ARRL 10m

David Gilbert

Any chance you could upload that recording to some place where we could
all access it?  It would be nice to be able to compare perceptions.  If
you edited the file to isolate the occurrences it shouldn't be too large.

73,
Dave   AB7E



On 12/13/2011 6:16 AM, Lu Romero wrote:

> I have sent my recording in already.  I heard some in my CW
> pileups. Some were zero beat issues but not all.
>
> -lu-W4LT-
>
> ====================
>
>
> Message: 6
> Date: Mon, 12 Dec 2011 10:43:04 -0700
> From: David Gilbert<[hidden email]>
> Subject: [Elecraft] K3 "blur" was a no-show during ARRL 10m
> To: Elecraft Reflector<[hidden email]>
> Message-ID:<[hidden email]>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
>
> Well, I recorded most of my time in the ARRL 10m contest
> this past
> weekend but I didn't save it.  I only had three or four
> situations where
> I thought possibly I was hearing some blurring of signals
> but they
> weren't definitive at all, and in those cases the signals
> were virtually
> zero beat so I chalked it up to that instead.  I was fairly
> seriously
> operating the contest (about 1,000 CW contacts) and running
> a frequency
> most of the time so I didn't go looking for other examples,
> and I was
> running low power so I rarely had more than three callers at
> a time.
>
> I was all primed to adjust RF Gain and manually switch
> roofing filters
> if the effect occurred, but it didn't for me this time.
> Sorry I
> couldn't come up with an example.
>
> Anyone else capture anything?
>
> 73,
> Dave   AB7E
>
>
>
>
>
>
>
______________________________________________________________
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
Reply | Threaded
Open this post in threaded view
|

Re: K3 "blur" was a no-show during ARRL 10m

Oliver Dröse
I would like to hear you it, too, Lu.

If you don't have any webspace please feel free to send it to me by mail and
I will gladly upload it on my site and provide the download link for the
list ...

Vy 73, Olli - DH8BQA
http://www.dh8bqa.de




----- Original Message -----
From: "David Gilbert" <[hidden email]>
To: <[hidden email]>
Cc: <[hidden email]>
Sent: Tuesday, December 13, 2011 6:55 PM
Subject: Re: [Elecraft] K3 "blur" was a no-show during ARRL 10m


>
> Any chance you could upload that recording to some place where we could
> all access it?  It would be nice to be able to compare perceptions.  If
> you edited the file to isolate the occurrences it shouldn't be too large.
>
> 73,
> Dave   AB7E
>
>
>
> On 12/13/2011 6:16 AM, Lu Romero wrote:
>> I have sent my recording in already.  I heard some in my CW
>> pileups. Some were zero beat issues but not all.
>>
>> -lu-W4LT-
>>
>> ====================
>>
>>
>> Message: 6
>> Date: Mon, 12 Dec 2011 10:43:04 -0700
>> From: David Gilbert<[hidden email]>
>> Subject: [Elecraft] K3 "blur" was a no-show during ARRL 10m
>> To: Elecraft Reflector<[hidden email]>
>> Message-ID:<[hidden email]>
>> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>>
>>
>> Well, I recorded most of my time in the ARRL 10m contest
>> this past
>> weekend but I didn't save it.  I only had three or four
>> situations where
>> I thought possibly I was hearing some blurring of signals
>> but they
>> weren't definitive at all, and in those cases the signals
>> were virtually
>> zero beat so I chalked it up to that instead.  I was fairly
>> seriously
>> operating the contest (about 1,000 CW contacts) and running
>> a frequency
>> most of the time so I didn't go looking for other examples,
>> and I was
>> running low power so I rarely had more than three callers at
>> a time.
>>
>> I was all primed to adjust RF Gain and manually switch
>> roofing filters
>> if the effect occurred, but it didn't for me this time.
>> Sorry I
>> couldn't come up with an example.
>>
>> Anyone else capture anything?
>>
>> 73,
>> Dave   AB7E
>>
>>
>>
>>
>>
>>
>>
> ______________________________________________________________
> 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
>
>
> -----
> eMail ist virenfrei.
> Von AVG uberpruft - www.avg.de
> Version: 10.0.1415 / Virendatenbank: 2102/4078 - Ausgabedatum: 13.12.2011
>

______________________________________________________________
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
Reply | Threaded
Open this post in threaded view
|

Re: K3 "blur" was a no-show during ARRL 10m

Bruce Beford-2
In reply to this post by David Gilbert
I have read with great interest the threads regarding "mush" or "blur" that
some have experienced in pile-up situations where several callers were near
or at the noise level, and all blended together.

I am not qualified to say whether or not I have experienced this specific
artifact. However, during last weekend's 10M contest I experienced some
interesting phenomena while working each day (at a leisurely pace) for about
3 hours on CW only.

My antenna at the time was a 176ft doublet fed with ladder line, from the
K3/KPA500 (amp was not really needed, but it was there). I would
occasionally switch to a coax-fed G5RV at 90 degrees to, and below the
176fter.

As these antennas are not unidirectional, I would often hear stations
short-path and long path at the same time, which would add to the perceived
"blur" or "mush".

It was also QUITE interesting to hear MYSELF call, as my own signal returned
to my receiver after circling the globe. The smooth QSK in the K3 made this
quite apparent.

Great fun.

72/73,
Bruce N1RX


______________________________________________________________
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
Reply | Threaded
Open this post in threaded view
|

Re: K3 "blur" was a no-show during ARRL 10m

s57aw
Hi Bruce,

It was really interesting... I was QRV for about 4 hours during ARRL 10m as
S50G (CW only) and it was interesting to hear last part of my transmission
(something like ET) after CQ... TEST. At the begging I was not sure what is
really happening with my K3  :-)

73 Robert, S57AW

It was also QUITE interesting to hear MYSELF call, as my own signal returned

> to my receiver after circling the globe. The smooth QSK in the K3 made this
> quite apparent.
>
> Great fun.
>
> 72/73,
> Bruce N1RX
>
>
> ______________________________________________________________
> 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
>
______________________________________________________________
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
Reply | Threaded
Open this post in threaded view
|

Re: K3 "blur" was a no-show during ARRL 10m

NZ0T
I heard very pronounced echoing via long path this last weekend.  I was working European DX on 17 CW and the echo was making it hard to copy DX stations at times.  Their long path echos, in some cases, were as strong as their direct path.  My own echo was the loudest I have ever heard in my nearly 30 years on the air. I also heard it on 10 meters but not as pronounced.  Methinks that may be the source of the "mush" reports?

73 Bill NZ0T
Reply | Threaded
Open this post in threaded view
|

Re: K3 "blur" was a no-show during ARRL 10m

Jim Brown-10
On 12/14/2011 5:42 PM, NZ0T wrote:
> Methinks that may be the source of the "mush" reports?

No. It's a very different problem, and is immediately recognizable once
you've figured out what's going on. I used to experience this in Chicago
to EU when I was using dipoles on 20M, and again here in Santa Cruz to
EU even with a 3-el Yagi.  It will show up for an hour or two, then go
away when one path becomes much stronger than the other.  When the two
paths are within about 6dB of each other,CW is almost impossible to copy.

73, Jim K9YC
______________________________________________________________
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
Reply | Threaded
Open this post in threaded view
|

Re: K3 "blur" was a no-show during ARRL 10m

Vic Rosenthal
When I lived in 4X I used to get up early before 20m was open and call CQ with QSK while
rotating my beam. I would listen for the echo of my own signal coming all the way around
the world. My theory was that the band must be open in the direction that the echo was
strongest. But I never got a QSO that way. Now I think that the loud echo was due to some
type of 'chordal propagation' and my signal was never coming down to earth in any
populated place. Of course I could have worked another station nearby by that path.

On 12/14/2011 5:55 PM, Jim Brown wrote:

> On 12/14/2011 5:42 PM, NZ0T wrote:
>> Methinks that may be the source of the "mush" reports?
> No. It's a very different problem, and is immediately recognizable once
> you've figured out what's going on. I used to experience this in Chicago
> to EU when I was using dipoles on 20M, and again here in Santa Cruz to
> EU even with a 3-el Yagi.  It will show up for an hour or two, then go
> away when one path becomes much stronger than the other.  When the two
> paths are within about 6dB of each other,CW is almost impossible to copy.
>
> 73, Jim K9YC
> ______________________________________________________________
> 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

--
Vic, K2VCO
Fresno CA
http://www.qsl.net/k2vco/

______________________________________________________________
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
Reply | Threaded
Open this post in threaded view
|

Re: K3 "blur" was a no-show during ARRL 10m

David Gilbert
In reply to this post by NZ0T

Nope.  It's not the same thing at all.  I've had lots of experience with
the kind of echo you mention and heard it several times during the 10m
contest this past weekend, but it doesn't sound at all like the in-band
mixer products we've been discussing.  For one very obvious difference,
we've all pointed out that the "blur" only occurs when there are
multiple signals ... the echo happens even with a single signal.

Dave   AB7E


On 12/14/2011 6:42 PM, NZ0T wrote:
> I heard very pronounced echoing via long path this last weekend.  I was
> working European DX on 17 CW and the echo was making it hard to copy DX
> stations at times.  Their long path echos, in some cases, were as strong as
> their direct path.  My own echo was the loudest I have ever heard in my
> nearly 30 years on the air. I also heard it on 10 meters but not as
> pronounced.  Methinks that may be the source of the "mush" reports?
>
> 73 Bill NZ0T
>
______________________________________________________________
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
Reply | Threaded
Open this post in threaded view
|

Re: K3 "blur" was a no-show during ARRL 10m

GM0ELP
In reply to this post by David Gilbert
The words "blur" and "mush" are confusing to me. The effect I heard whilst running on 80m during CQWW (CW) 2010 was the following:

A very slight raise in the noise floor then a random partial letter a few seconds later.

If this is what is meant by "blur" and "mush" then I have noticed the effect. I was running and had just finished my last CQ call (I was considering a QSY) when I first noticed it.  I decided to call CQ again and noticed the same effect again. The penny finally dropped that the slight rise in noise floor was actually a pile-up of similar strength stations calling me (all S5, with S4 noise floor). To test my theory I sent back 2 letters which clearly appeared on their own 2 or 3 seconds after my last CQ call and low and behold a single US station came back Q5. I worked another 10 or so stations in exactly the same way until the effect disappeared as did the pile-up (probably all pretty hacked off with how slow I was working through them). I later discovered I had been spotted by KC1XX.

The reason for the random partial letter a few seconds after your CQ call, is that the pile up seems to "disappear" until only the last few callers are still calling. Usually these stations have the longest callsign or sent their callsign twice.

The difficult thing about this effect is that first you have to realise what is going on. If you are calling CQ with hardly any gap between each call, you will not know the effect has taken place (you may be unaware a pile up is there until it has thinned out), as tail end callers will only become apparent when you are transmitting again. You have to pause between CQ calls (much longer than usual) before you get the hint of what is going on.

Not wanting to have to pause long enough between every CQ call to catch this effect again, I haven't noticed it recently (ignorance is bliss).

73

Doug MM3T