K3- SWR accuracy

[Nr4c]

Gang,

 

I have recently built my K3 and have had it on the air about 3 weeks.  I
started small, with 10 watts, added the PA3 and DVR.  My next purchase will
be the ATU module.  In the meantime, I am using an LDG-200Pro Auto-Tuner.
It works great, but I have noticed that especially on 40 meters, I can have
the tuner go through a 'tune' cycle, and it will show 1.0:1 SWR, but my K3
shows 1.3 ro 1.7 up to 1.8 to 1 SWR.

 

I recorded a short call response with the DVR and when I play it back, the
radio shows SWR of more than 1:1 but the tuner indicates full power and low
SWR.  Which do I believe?  Most other bands are normal, with tuner/radio
agreement.   But not always, and especially on 40.

 

I tried to manually tune the tuner to 1:1 and usually only took a couple of
clicks, but no matter what I did, I could not get it to hold those settings;
ie, when I went back to the frequency I 'manually' tuned, and tried to
memorize, it tuned again, often only a Memory Tune, but went back to it's
settings of 1.3:1.

 

Any ideas?

 

...bc      K3  #4536  (nr4c)

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[Jorge Diez - CX6VM]

Hi Bill,

I recently purchased a powerMaster from arraysolutions and have the same
problems.

Readings are different in the Powermaster and in the K3, .3 to .7 in
diference.

You have some coax loops going from SWR and AMP, so maybe some diference
there?.  Anyway is not reading the same...

73,
Jorge
CX6VM/CW5W
K3 #4077

-----Mensaje original-----
De: [hidden email]
[mailto:[hidden email]] En nombre de Bill Conkling
Enviado el: Lunes, 06 de Septiembre de 2010 01:25 a.m.
Para: [hidden email]
Asunto: [Elecraft] K3- SWR accuracy

Gang,

 

I have recently built my K3 and have had it on the air about 3 weeks.  I
started small, with 10 watts, added the PA3 and DVR.  My next purchase will
be the ATU module.  In the meantime, I am using an LDG-200Pro Auto-Tuner.
It works great, but I have noticed that especially on 40 meters, I can have
the tuner go through a 'tune' cycle, and it will show 1.0:1 SWR, but my K3
shows 1.3 ro 1.7 up to 1.8 to 1 SWR.

 

I recorded a short call response with the DVR and when I play it back, the
radio shows SWR of more than 1:1 but the tuner indicates full power and low
SWR.  Which do I believe?  Most other bands are normal, with tuner/radio
agreement.   But not always, and especially on 40.

 

I tried to manually tune the tuner to 1:1 and usually only took a couple of
clicks, but no matter what I did, I could not get it to hold those settings;
ie, when I went back to the frequency I 'manually' tuned, and tried to
memorize, it tuned again, often only a Memory Tune, but went back to it's
settings of 1.3:1.

 

Any ideas?

 

...bc      K3  #4536  (nr4c)

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[Nr4c]

Gang,

My antenna is a loop (approx 300 foot, non resonant, nearly horizontal at
average 35 feet)  with 450 ohm ladder line to the window feed thru.  Inside
the window is a 9" length of ladder line, and a balun.  Now six feet of
RG-8X to the LDG and 18" of coax to the K3.

Using the same 18" jumper to the Dummy Load, I get 1:1 all across the bands
on the K3 SWR readout.

...bc

-----Original Message-----
From: Steve Ellington [mailto:[hidden email]]
Sent: Monday, September 06, 2010 9:18 AM
To: Bill Conkling
Subject: Re: [Elecraft] K3- SWR accuracy

Bill
You probably have some "common mode" currents on the shield of the coax
causing the meters to read nutty. I'm curious what kind of feedline and
antenna you are using and how long is the coax between the K3 and your LDG?
I use an MFJ-998 which is 100 feet from the K3. The meters never read the
same because of all this coax. The K3's meter is really accurate however. I
also have the K3 internal tuner and it is really good. Matches almost
anything.
Steve

----- Original Message -----
From: "Bill Conkling" <[hidden email]>
To: <[hidden email]>
Sent: Monday, September 06, 2010 12:25 AM
Subject: [Elecraft] K3- SWR accuracy

> Gang,
>
>
>
> I have recently built my K3 and have had it on the air about 3 weeks.  I
> started small, with 10 watts, added the PA3 and DVR.  My next purchase
> will
> be the ATU module.  In the meantime, I am using an LDG-200Pro Auto-Tuner.
> It works great, but I have noticed that especially on 40 meters, I can
> have
> the tuner go through a 'tune' cycle, and it will show 1.0:1 SWR, but my K3
> shows 1.3 ro 1.7 up to 1.8 to 1 SWR.
>
>
>
> I recorded a short call response with the DVR and when I play it back, the
> radio shows SWR of more than 1:1 but the tuner indicates full power and
> low
> SWR.  Which do I believe?  Most other bands are normal, with tuner/radio
> agreement.   But not always, and especially on 40.
>
>
>
> I tried to manually tune the tuner to 1:1 and usually only took a couple
> of
> clicks, but no matter what I did, I could not get it to hold those
> settings;
> ie, when I went back to the frequency I 'manually' tuned, and tried to
> memorize, it tuned again, often only a Memory Tune, but went back to it's
> settings of 1.3:1.
>
>
>
> Any ideas?
>
>
>
> ...bc      K3  #4536  (nr4c)
>
> ______________________________________________________________
> 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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