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K3 S meter oddities

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Vic Rosenthal

Re: KAT2 with EFHW antenna

Just speculating -- I bet a half-wavelength wire in inverted-L configuration fed at the
base with a parallel-tuned circuit would work well. The high-current part of the vertical
piece would be at the top, there would be plenty of current in the horizontal part too,
and very little local ground current.

On 8/24/2011 6:54 AM, William Ravenel wrote:

> Steve Yates, AA5TB, has a very informative web page on EFHW antennas and how to build a
> parallel tuned circuit with a link coupled feed at the radio end to reduce the 1800 to
> 5000 ohm impedance to a 50 ohm non-reactive load. He has examples of both QRP and QRO
> versions of the circuit. I built the QRP version which uses a polyvaricon capacitor
> (available through Hendrix Kits among other sources) to create a very small tuning
> device that will match resonant End Fed half wavelength antennas on 40m, 30m, 20m, and
> 17m. I use it mostly with a 33 foot wire on 20m raised on a 31 foot Jackite fiberglass
> pole and have had fun working DX with 5 watts. It is easy to change bands by exchanging
> the wire with one cut for the band of interest. I do not use a counterpoise and do not
> have any trouble at the rig. Steve explains why this works. For higher power a one
> meter counterpoise helps. I use this antenna with a K1 and K2, both with internal
> antenna tuners. The tuners are not needed, but I leave them activated to easily
> compensate for any small mismatch across the band.
>
> Steve's page is found at http://aa5tb.com/efha.html
>
> William Ravenel, AI4VE ______________________________________________________________

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

Re: KAT2 with EFHW antenna

In reply to this post by Phil Shepard

Phil,

You might try a 67' length of wire (EFFW antenna). I've used that (and a
32' EFHW) on 20 a lot with my K1 with the KAT1 installed...tunes to
close to 1:1 just fine.

Have fun at Crater Lake. There are some neat places along the rim for
hamming. It's a 2000 mile drive (one way) for me but I've gotten there
twice within the past several years. See
http://www.prismnet.com/~nielw/qrp/CraterLake_july04.jpg and
http://w0vlz.blogspot.com/2009/08/after-three-weeks-5300-miles-and-12.html

73,
Niel - W0VLZ

> Message: 2
> Date: Tue, 23 Aug 2011 16:00:17 -0700
> From: "Phillip Shepard"<[hidden email]>
> Subject: [Elecraft] KAT2 with EFHW antenna
> To:<[hidden email]>
> Message-ID:<[hidden email]>
> Content-Type: text/plain; charset="us-ascii"
>
> I have been using my K2 with an MFJ tuner to feed an end fed halfwave wire
> for portable use (like SOTA). The 20m antenna is 33' long and I use one or
> two 16' counterpoise wires. It seems to work well for what it is and 10W.
> I just built and installed the KAT2 ATU into the K2 to lighten my pack by
> the loss of the MFJ. The KAT2 tuner checked out fine on the bench, but it
> had a very hard time getting a good match to the antenna. In AUTO mode, it
> only got the SWR down to about 5:1. I put it in ALT mode, and it spent a
> long time searching before it got down to between 3:1 and 4:1, depending on
> the 20m frequency. I added about 2" of wire to the antenna, and the tuer
> got down to about 2:1 to 2.5:1. I added another foot of wire (now 36'), and
> it got down to about 1.5:1. Five or six feet added yielded a perfect match
> (1:1). So I now have a 39' wire for 20m use.
>
> Is this normal? Should the KAT2 be able to more easily match the 33'
> halfwave antenna? Thank you.
>
> 73,
> Phl, NS7P
>
>

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David Gilbert

Re: KAT2 with EFHW antenna

I'm not sure I see the advantage. A full wave end fed antenna would
theoretically have the same very high feedpoint impedance, and would
additionally blow most of it's radiated energy at a fairly high angle
off the ends of the antenna instead of broadside at a lower angle. If
you find it that easy to tune, I suspect that electrically it really
isn't that close to a full wavelength ... possibly because of coupling
to earth (if it is low) or nearby structures. Either that or there is a
lot of loss in the system somewhere.

73,
Dave AB7E

On 8/24/2011 2:14 PM, Niel Wiegand wrote:

> Phil,
>
> You might try a 67' length of wire (EFFW antenna). I've used that (and a
> 32' EFHW) on 20 a lot with my K1 with the KAT1 installed...tunes to
> close to 1:1 just fine.
>
> Have fun at Crater Lake. There are some neat places along the rim for
> hamming. It's a 2000 mile drive (one way) for me but I've gotten there
> twice within the past several years. See
> http://www.prismnet.com/~nielw/qrp/CraterLake_july04.jpg and
> http://w0vlz.blogspot.com/2009/08/after-three-weeks-5300-miles-and-12.html
>
> 73,
> Niel - W0VLZ
>
>
>
>> Message: 2
>> Date: Tue, 23 Aug 2011 16:00:17 -0700
>> From: "Phillip Shepard"<[hidden email]>
>> Subject: [Elecraft] KAT2 with EFHW antenna
>> To:<[hidden email]>
>> Message-ID:<[hidden email]>
>> Content-Type: text/plain; charset="us-ascii"
>>
>> I have been using my K2 with an MFJ tuner to feed an end fed halfwave wire
>> for portable use (like SOTA). The 20m antenna is 33' long and I use one or
>> two 16' counterpoise wires. It seems to work well for what it is and 10W.
>> I just built and installed the KAT2 ATU into the K2 to lighten my pack by
>> the loss of the MFJ. The KAT2 tuner checked out fine on the bench, but it
>> had a very hard time getting a good match to the antenna. In AUTO mode, it
>> only got the SWR down to about 5:1. I put it in ALT mode, and it spent a
>> long time searching before it got down to between 3:1 and 4:1, depending on
>> the 20m frequency. I added about 2" of wire to the antenna, and the tuer
>> got down to about 2:1 to 2.5:1. I added another foot of wire (now 36'), and
>> it got down to about 1.5:1. Five or six feet added yielded a perfect match
>> (1:1). So I now have a 39' wire for 20m use.
>>
>> Is this normal? Should the KAT2 be able to more easily match the 33'
>> halfwave antenna? Thank you.
>>
>> 73,
>> Phl, NS7P
>>
>>

Don Wilhelm-4

Re: KAT2 with EFHW antenna

Actually Dave, a full wavelength wire will have a " 4 leaf clover"
pattern - that is neither broadside to the antenna, nor off the ends.
Check out the pattern for a 1 wavelength long wire in the ARRL Antenna
Book. The maximum radiation is about 28 degrees from the wire - the
radiation from the end is almost zero.

The elevation angle of maximum radiation is similar to a half wave
dipole - about 15 degrees with a lesser lobe at 45 degrees (that is for
a wire 70 feet high, at lower heights, the angle will be greater).

73,
Don W3FPR

On 8/24/2011 5:34 PM, David Gilbert wrote:

>
> I'm not sure I see the advantage. A full wave end fed antenna would
> theoretically have the same very high feedpoint impedance, and would
> additionally blow most of it's radiated energy at a fairly high angle
> off the ends of the antenna instead of broadside at a lower angle. If
> you find it that easy to tune, I suspect that electrically it really
> isn't that close to a full wavelength ... possibly because of coupling
> to earth (if it is low) or nearby structures. Either that or there is a
> lot of loss in the system somewhere.
>
> 73,
> Dave AB7E
>

AC7AC

Re: KAT2 with EFHW antenna

In reply to this post by David Gilbert

CONTENTS DELETED

The author has deleted this message.

David Gilbert

Re: KAT2 with EFHW antenna

In reply to this post by Don Wilhelm-4

Yes, Don ... you are totally correct. For some reason I was thinking
about a full wave antenna fed at the 25% point (I have built such
antennas before), which looks like two colinear half waves fed out of
phase. The current phasing along the antenna would indeed be much
different and give a cloverleaf pattern if it were end fed. I
wholeheartedly apologize for any confusion I may have created.

73 and thanks for catching my mistake.

Dave AB7E

On 8/24/2011 3:23 PM, Don Wilhelm wrote:

> Actually Dave, a full wavelength wire will have a " 4 leaf clover"
> pattern - that is neither broadside to the antenna, nor off the ends.
> Check out the pattern for a 1 wavelength long wire in the ARRL Antenna
> Book. The maximum radiation is about 28 degrees from the wire - the
> radiation from the end is almost zero.
>
> The elevation angle of maximum radiation is similar to a half wave
> dipole - about 15 degrees with a lesser lobe at 45 degrees (that is
> for a wire 70 feet high, at lower heights, the angle will be greater).
>
> 73,
> Don W3FPR
>
> On 8/24/2011 5:34 PM, David Gilbert wrote:
>>
>> I'm not sure I see the advantage. A full wave end fed antenna would
>> theoretically have the same very high feedpoint impedance, and would
>> additionally blow most of it's radiated energy at a fairly high angle
>> off the ends of the antenna instead of broadside at a lower angle. If
>> you find it that easy to tune, I suspect that electrically it really
>> isn't that close to a full wavelength ... possibly because of coupling
>> to earth (if it is low) or nearby structures. Either that or there is a
>> lot of loss in the system somewhere.
>>
>> 73,
>> Dave AB7E
>>
>

Guy, K2AV

Re: KAT2 with EFHW antenna

Sorry to interject, but a fullwave fed at the 25% point has a clover leaf
pattern. It only has the two halfwaves in phase colinear behavior when fed
very near the center. Even fed at 45% it has a significant cloverleaf lobe
and a NULL in the center Easy to verify with any modeling program. 73,
Guy.

On Wed, Aug 24, 2011 at 8:37 PM, David Gilbert <[hidden email]>wrote:

>
> Yes, Don ... you are totally correct. For some reason I was thinking
> about a full wave antenna fed at the 25% point (I have built such
> antennas before), which looks like two colinear half waves fed out of
> phase. The current phasing along the antenna would indeed be much
> different and give a cloverleaf pattern if it were end fed. I
> wholeheartedly apologize for any confusion I may have created.
>
> 73 and thanks for catching my mistake.
>
> Dave AB7E
>
>
> On 8/24/2011 3:23 PM, Don Wilhelm wrote:
> > Actually Dave, a full wavelength wire will have a " 4 leaf clover"
> > pattern - that is neither broadside to the antenna, nor off the ends.
> > Check out the pattern for a 1 wavelength long wire in the ARRL Antenna
> > Book. The maximum radiation is about 28 degrees from the wire - the
> > radiation from the end is almost zero.
> >
> > The elevation angle of maximum radiation is similar to a half wave
> > dipole - about 15 degrees with a lesser lobe at 45 degrees (that is
> > for a wire 70 feet high, at lower heights, the angle will be greater).
> >
> > 73,
> > Don W3FPR
> >
> > On 8/24/2011 5:34 PM, David Gilbert wrote:
> >>
> >> I'm not sure I see the advantage. A full wave end fed antenna would
> >> theoretically have the same very high feedpoint impedance, and would
> >> additionally blow most of it's radiated energy at a fairly high angle
> >> off the ends of the antenna instead of broadside at a lower angle. If
> >> you find it that easy to tune, I suspect that electrically it really
> >> isn't that close to a full wavelength ... possibly because of coupling
> >> to earth (if it is low) or nearby structures. Either that or there is a
> >> lot of loss in the system somewhere.
> >>
> >> 73,
> >> Dave AB7E
> >>
> >
> ______________________________________________________________
> Elecraft mailing list
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David Gilbert

Re: KAT2 with EFHW antenna

Yup ... I was wrong again, but the trouble is I can't figure out why. I
mean, it's easy to verify the cloverleaf pattern with EZNEC and I have
done so, but I know that I have modeled something similar with an
off-center feed in the past and gotten an end-fire pattern. As soon as
I figure out what that was I'll come back here and try to clear up the
confusion I have caused, but in the meantime let's all just agree that I
don't know what I'm talking about.

sigh ...

73,
Dave AB7E

On 8/25/2011 11:13 AM, Guy Olinger K2AV wrote:

> Sorry to interject, but a fullwave fed at the 25% point has a clover
> leaf pattern. It only has the two halfwaves in phase colinear
> behavior when fed very near the center. Even fed at 45% it has a
> significant cloverleaf lobe and a NULL in the center Easy to verify
> with any modeling program. 73, Guy.
>
> On Wed, Aug 24, 2011 at 8:37 PM, David Gilbert
> <[hidden email] <mailto:[hidden email]>> wrote:
>
>
> Yes, Don ... you are totally correct. For some reason I was thinking
> about a full wave antenna fed at the 25% point (I have built such
> antennas before), which looks like two colinear half waves fed out of
> phase. The current phasing along the antenna would indeed be much
> different and give a cloverleaf pattern if it were end fed. I
> wholeheartedly apologize for any confusion I may have created.
>
> 73 and thanks for catching my mistake.
>
> Dave AB7E
>
>
> On 8/24/2011 3:23 PM, Don Wilhelm wrote:
> > Actually Dave, a full wavelength wire will have a " 4 leaf clover"
> > pattern - that is neither broadside to the antenna, nor off the
> ends.
> > Check out the pattern for a 1 wavelength long wire in the ARRL
> Antenna
> > Book. The maximum radiation is about 28 degrees from the wire - the
> > radiation from the end is almost zero.
> >
> > The elevation angle of maximum radiation is similar to a half wave
> > dipole - about 15 degrees with a lesser lobe at 45 degrees (that is
> > for a wire 70 feet high, at lower heights, the angle will be
> greater).
> >
> > 73,
> > Don W3FPR
> >
> > On 8/24/2011 5:34 PM, David Gilbert wrote:
> >>
> >> I'm not sure I see the advantage. A full wave end fed antenna
> would
> >> theoretically have the same very high feedpoint impedance, and
> would
> >> additionally blow most of it's radiated energy at a fairly high
> angle
> >> off the ends of the antenna instead of broadside at a lower
> angle. If
> >> you find it that easy to tune, I suspect that electrically it
> really
> >> isn't that close to a full wavelength ... possibly because of
> coupling
> >> to earth (if it is low) or nearby structures. Either that or
> there is a
> >> lot of loss in the system somewhere.
> >>
> >> 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]
> <mailto:[hidden email]>
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>
>

Guy, K2AV

Re: KAT2 with EFHW antenna

I've gotten to the point, that before I say anything about a model, I
actually run it and play with it, to make sure I haven't forgotten
something, or remembered something wrong.

As to that particular antenna a center fed half wave antenna is troublesome.
The better version of that if one wants that pattern is the extended double
zepp, two 5/8 waves fed in phase, where you are feeding a lower impedance at
the center, and it's a far less cranky antenna. The double zepp maintains
its essential shape fed at 45% whereas the halfwave converts to cloverleaf.

That's ancient knowledge, garnered by experience in the 40's and 50's
without the benefit of software. These days if you can't look it up for
free on the internet, it's forgotten.

73, Guy.

On Fri, Aug 26, 2011 at 12:17 PM, David Gilbert <[hidden email]>wrote:

>
> Yup ... I was wrong again, but the trouble is I can't figure out why. I
> mean, it's easy to verify the cloverleaf pattern with EZNEC and I have done
> so, but I know that I have modeled something similar with an off-center feed
> in the past and gotten an end-fire pattern. As soon as I figure out what
> that was I'll come back here and try to clear up the confusion I have
> caused, but in the meantime let's all just agree that I don't know what I'm
> talking about.
>
> sigh ...
>
> 73,
> Dave AB7E
>
>
>
>
>
> On 8/25/2011 11:13 AM, Guy Olinger K2AV wrote:
>
> Sorry to interject, but a fullwave fed at the 25% point has a clover leaf
> pattern. It only has the two halfwaves in phase colinear behavior when fed
> very near the center. Even fed at 45% it has a significant cloverleaf lobe
> and a NULL in the center Easy to verify with any modeling program. 73,
> Guy.
>
> On Wed, Aug 24, 2011 at 8:37 PM, David Gilbert <[hidden email]>wrote:
>
>>
>> Yes, Don ... you are totally correct. For some reason I was thinking
>> about a full wave antenna fed at the 25% point (I have built such
>> antennas before), which looks like two colinear half waves fed out of
>> phase. The current phasing along the antenna would indeed be much
>> different and give a cloverleaf pattern if it were end fed. I
>> wholeheartedly apologize for any confusion I may have created.
>>
>> 73 and thanks for catching my mistake.
>>
>> Dave AB7E
>>
>>
>> On 8/24/2011 3:23 PM, Don Wilhelm wrote:
>> > Actually Dave, a full wavelength wire will have a " 4 leaf clover"
>> > pattern - that is neither broadside to the antenna, nor off the ends.
>> > Check out the pattern for a 1 wavelength long wire in the ARRL Antenna
>> > Book. The maximum radiation is about 28 degrees from the wire - the
>> > radiation from the end is almost zero.
>> >
>> > The elevation angle of maximum radiation is similar to a half wave
>> > dipole - about 15 degrees with a lesser lobe at 45 degrees (that is
>> > for a wire 70 feet high, at lower heights, the angle will be greater).
>> >
>> > 73,
>> > Don W3FPR
>> >
>> > On 8/24/2011 5:34 PM, David Gilbert wrote:
>> >>
>> >> I'm not sure I see the advantage. A full wave end fed antenna would
>> >> theoretically have the same very high feedpoint impedance, and would
>> >> additionally blow most of it's radiated energy at a fairly high angle
>> >> off the ends of the antenna instead of broadside at a lower angle. If
>> >> you find it that easy to tune, I suspect that electrically it really
>> >> isn't that close to a full wavelength ... possibly because of coupling
>> >> to earth (if it is low) or nearby structures. Either that or there is
>> a
>> >> lot of loss in the system somewhere.
>> >>
>> >> 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
>>
>
>

w0mu

Re: K3 S meter oddities

In reply to this post by Phil Shepard

I have also noticed that if you lower the rf gain that that meter does
not deflect all to S9 like my other K3 that does not exhibit this issue.

On 8/11/2011 5:44 PM, Phillip Shepard wrote:

> It actually does it with a blank phone plug inserted. As soon as the plug
> goes in, the S meter jumps up. The signal itself does not change, just the
> meter reading. I have not examined the area around the jack inside to see
> if there is anything odd. That may be next.
>
> Phil
>
> -----Original Message-----
> From: [hidden email]
> [mailto:[hidden email]]On Behalf Of Bruce Beford
> Sent: Thursday, August 11, 2011 2:54 PM
> To: [hidden email]
> Subject: Re: [Elecraft] K3 S meter oddities
>
>
>> When I plug my headphones into the K3 the S Meter jumps up about 5 s
>> units. This unit is running 4.31 FW. I obviously have not tried new
> 4.39.
>
>> Just curious if anyone else has seen this.
>> Mike W0MU
> My K3 s/n 559 running 4.39 does -not- exhibit this behavior. As far as I can
> recall, it never has. Using Koss and Yamaha phones here. On what bands/under
> what conditions? Is it possible you are actually coupling some kind of RF
> (not necessarily ham transmissions, but something else in the house/shack)
> back into the rig from within your environment via the phones lead?
> GL,
> Bruce, N1RX
>
>
>
> ______________________________________________________________
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--
J6/W0MU November 21 - December 1 2011 CQ WW DX CW

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KK7P

Re: K3 S meter oddities

Does it do it with both headphone jacks, or just the front, or just the
rear?

73,

Lyle KK7P

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