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Portable Antennas (Is there an "easy" button?)

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David Cutter

Re: Portable Antennas (Is there an "easy" button?)

There are some great resources out there: I'm surprised no-one has
mentioned the near end-fed QEX articles written by Ron W6WO or

AA5TB http://www.aa5tb.com/efha.html

or W8JI
http://www.w8ji.com/end-fed_1_2_wave_matching_system_end%20feed.htm

David
G3UNA
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David Cutter

Re: Portable Antennas (near end fed)

What I particularly like about the near end fed is that you are more in
control of the local stray capacitances and such like and you only need
one slender wire in the sky. I wrote a power point on the subject which
needs a bit of massage but I can send it to you for interest.

73
David
G3UNA

On 09/05/2012 07:32, Stephen Prior wrote:

> David
>
> Many thanks for those references. I'm pleased that my longtime belief
> that you simply cannot get away without a counterpoise, even a
> 'counterpoise of sorts' has been confirmed. I really must subscribe
> to QEX.
>
> 73 Stephen G4SJP
>
> On Wednesday, 9 May 2012, David Cutter wrote:
>
> There are some great resources out there: I'm surprised no-one has
> mentioned the near end-fed QEX articles written by Ron W6WO or
>
> AA5TB http://www.aa5tb.com/efha.html
>
> or W8JI
> http://www.w8ji.com/end-fed_1_2_wave_matching_system_end%20feed.htm
>
>
>
> David
> G3UNA
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email] <javascript:;>
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>
>
>
> --
> Sent from Gmail Mobile

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John Huggins, kx4o

Re: Portable Antennas (Is there an "easy" button?)

In reply to this post by David Cutter

Indeed AA5TB EHFA's web page was an eye opener for me.

I've since studied the PAR (LNR) multi-band (40, 20 and 10) EFHW product
with particular focus on the transformer box.

http://www.hamradio.me/antennas/lnr-precision-ef-102040mkii-examination.html

http://www.hamradio.me/antennas/lnr-precision-ef-102040mkii-test-data.html

Of particular note are the resistance tests showing the wideband nature
of the standalone matchbox to function from 60m to 10m with no tuning.
This is not to imply, however, the matchbox/wire combo is multi-band.

This clever little matchbox seems like an "easy button."

With that in mind, can anyone report what happens when the K2 (or any
Elecraft) antenna tuner attempts to drive something like the LNR
40/20/10 matchbox/wire combo on some other frequency?

Thanks.
John, kx4o

On 5/9/12 2:49 AM, David Cutter wrote:

> There are some great resources out there: I'm surprised no-one has
> mentioned the near end-fed QEX articles written by Ron W6WO or
>
> AA5TB http://www.aa5tb.com/efha.html
>
> or W8JI
> http://www.w8ji.com/end-fed_1_2_wave_matching_system_end%20feed.htm
>
>
>
> David
> G3UNA
> ______________________________________________________________
> 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

Joseph Trombino, Jr

Re: Portable Antennas (Is there an "easy" button?)

Howdy John:

I use the PAR 40/20/10 for my field ops...I loaded this antenna up on 15M using the KAT2 tuner in my K2 and worked some DX with it.

It loaded up easily and seemed to perform OK on 15M....so I guess it is possible.

73, Joe W2KJ
I QRP, therefore I am

> Indeed AA5TB EHFA's web page was an eye opener for me.
>
> I've since studied the PAR (LNR) multi-band (40, 20 and 10) EFHW product
> with particular focus on the transformer box.
>
> http://www.hamradio.me/antennas/lnr-precision-ef-102040mkii-examination.html
>
> http://www.hamradio.me/antennas/lnr-precision-ef-102040mkii-test-data.html
>
> Of particular note are the resistance tests showing the wideband nature
> of the standalone matchbox to function from 60m to 10m with no tuning.
> This is not to imply, however, the matchbox/wire combo is multi-band.
>
> This clever little matchbox seems like an "easy button."
>
> With that in mind, can anyone report what happens when the K2 (or any
> Elecraft) antenna tuner attempts to drive something like the LNR
> 40/20/10 matchbox/wire combo on some other frequency?
>
> Thanks.
> John, kx4o
>

k6dgw

Re: Portable Antennas (near end fed)

In reply to this post by David Cutter

I haven't been following this thread closely but has anyone mentioned a
small magnetic loop like the Alex-Loop? I've got a good SOTA friend who
uses one and loves it.

73,

Fred K6DGW
- Northern California Contest Club
- CU in the 2012 Cal QSO Party 6-7 Oct 2012
- www.cqp.org

On 5/9/2012 2:47 AM, David Cutter wrote:
> What I particularly like about the near end fed is that you are more in
> control of the local stray capacitances and such like and you only need
> one slender wire in the sky. I wrote a power point on the subject which
> needs a bit of massage but I can send it to you for interest.

______________________________________________________________
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Stephen G4SJP

Re: Portable Antennas (near end fed)

Hi Fred

I have been very tempted by the Alex-loop, but in the meantime have just
bought one of G4TPH's loops which I shall put through its paces when the
weather improves! I should imagine that the insensitivity to electric
fields in the near field would be an advantage in electrically noisy
environments. Even a campsite can be very noisy with the inverters from RVs
and the like spewing out rf everywhere.

I'm spoilt for choice of antennas to play with once the KX3 arrives!

73 Stephen G4SJP

On Wednesday, 9 May 2012, Fred Jensen wrote:

> I haven't been following this thread closely but has anyone mentioned a
> small magnetic loop like the Alex-Loop? I've got a good SOTA friend who
> uses one and loves it.
>
> 73,
>
> Fred K6DGW
> - Northern California Contest Club
> - CU in the 2012 Cal QSO Party 6-7 Oct 2012
> - www.cqp.org
>
> On 5/9/2012 2:47 AM, David Cutter wrote:
> > What I particularly like about the near end fed is that you are more in
> > control of the local stray capacitances and such like and you only need
> > one slender wire in the sky. I wrote a power point on the subject which
> > needs a bit of massage but I can send it to you for interest.
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email] <javascript:;>
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>

David Cutter

Re: Portable Antennas (mag loop)

It will be quiet on receive and quiet on transmit, however much power
you put into it, until it melts, that is. I'd love to know where he
gets his efficiency figures - perhaps you can ask him. Putting steel
washers at each aluminium joint turned me off completely along with the
dinky receiving capacitor.

I'm quite taken by the Midnight Loop from N2APB and N2CX, mainly because
I built something similar 20 years ago, only a lot bigger! See

http://www.midnightdesignsolutions.com/MidnightLoop/Midnight%20Loop%20%28Mar%2011a%29.pdf

David
G3UNA

On 10/05/2012 07:55, Stephen Prior wrote:

> Hi Fred
>
> I have been very tempted by the Alex-loop, but in the meantime have just
> bought one of G4TPH's loops which I shall put through its paces when the
> weather improves! I should imagine that the insensitivity to electric
> fields in the near field would be an advantage in electrically noisy
> environments. Even a campsite can be very noisy with the inverters from RVs
> and the like spewing out rf everywhere.
>
> I'm spoilt for choice of antennas to play with once the KX3 arrives!
>
> 73 Stephen G4SJP
>
> On Wednesday, 9 May 2012, Fred Jensen wrote:
>
>> I haven't been following this thread closely but has anyone mentioned a
>> small magnetic loop like the Alex-Loop? I've got a good SOTA friend who
>> uses one and loves it.
>>
>> 73,
>>
>> Fred K6DGW
>> - Northern California Contest Club
>> - CU in the 2012 Cal QSO Party 6-7 Oct 2012
>> - www.cqp.org

CRAIG W BEHRENS

Re: Portable Antennas (mag loop)

Absolutely a 1st class project and paper -- This is how it's done!
I really enjoyed reading and studying it Thanks for pointing out this paper, David.
And, thanks for sharing your ideas and projects, Joe and George!
72/73 & DX,
Craig W. Behrens -- NM4T

> Date: Thu, 10 May 2012 11:30:25 +0000
> From: [hidden email]
> To: [hidden email]
> Subject: Re: [Elecraft] Portable Antennas (mag loop)
>
> It will be quiet on receive and quiet on transmit, however much power
> you put into it, until it melts, that is. I'd love to know where he
> gets his efficiency figures - perhaps you can ask him. Putting steel
> washers at each aluminium joint turned me off completely along with the
> dinky receiving capacitor.
>
> I'm quite taken by the Midnight Loop from N2APB and N2CX, mainly because
> I built something similar 20 years ago, only a lot bigger! See
>
> http://www.midnightdesignsolutions.com/MidnightLoop/Midnight%20Loop%20%28Mar%2011a%29.pdf
>
> David
> G3UNA
>
>
> On 10/05/2012 07:55, Stephen Prior wrote:
> > Hi Fred
> >
> > I have been very tempted by the Alex-loop, but in the meantime have just
> > bought one of G4TPH's loops which I shall put through its paces when the
> > weather improves! I should imagine that the insensitivity to electric
> > fields in the near field would be an advantage in electrically noisy
> > environments. Even a campsite can be very noisy with the inverters from RVs
> > and the like spewing out rf everywhere.
> >
> > I'm spoilt for choice of antennas to play with once the KX3 arrives!
> >
> > 73 Stephen G4SJP
> >
> > On Wednesday, 9 May 2012, Fred Jensen wrote:
> >
> >> I haven't been following this thread closely but has anyone mentioned a
> >> small magnetic loop like the Alex-Loop? I've got a good SOTA friend who
> >> uses one and loves it.
> >>
> >> 73,
> >>
> >> Fred K6DGW
> >> - Northern California Contest Club
> >> - CU in the 2012 Cal QSO Party 6-7 Oct 2012
> >> - www.cqp.org
> ______________________________________________________________
> 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

Arthur Burke

Re: Portable Antennas (mag loop)

In reply to this post by David Cutter

I bookmarked the site - thank you. However, I didn't get very far the first
time when I saw the comment "....must be 1/2 wavelength above the ground..."

Still would like to go back and review the entire article.

Brings back a humorous dialog from years ago. One ham expressed the desire
to build a "....good, but short, 40 meter beam..." It was suggested he
shorten the beam until it was ultimately a 50-ohm resistor of sufficient
girth to accept reasonable power levels. Chuckles followed.

Then, someone who apparently didn't pick up on the tongue-in-cheek, frowned
and noted that the 50-ohm resistor would work even better if it was at
least a couple wavelengths in the air.

Art - N4PJ

On Thu, May 10, 2012 at 7:30 AM, David Cutter <[hidden email]> wrote:

> It will be quiet on receive and quiet on transmit, however much power
> you put into it, until it melts, that is. I'd love to know where he
> gets his efficiency figures - perhaps you can ask him. Putting steel
> washers at each aluminium joint turned me off completely along with the
> dinky receiving capacitor.
>
> I'm quite taken by the Midnight Loop from N2APB and N2CX, mainly because
> I built something similar 20 years ago, only a lot bigger! See
>
>
> http://www.midnightdesignsolutions.com/MidnightLoop/Midnight%20Loop%20%28Mar%2011a%29.pdf
>
> David
> G3UNA
>
>
> On 10/05/2012 07:55, Stephen Prior wrote:
> > Hi Fred
> >
> > I have been very tempted by the Alex-loop, but in the meantime have just
> > bought one of G4TPH's loops which I shall put through its paces when the
> > weather improves! I should imagine that the insensitivity to electric
> > fields in the near field would be an advantage in electrically noisy
> > environments. Even a campsite can be very noisy with the inverters from
> RVs
> > and the like spewing out rf everywhere.
> >
> > I'm spoilt for choice of antennas to play with once the KX3 arrives!
> >
> > 73 Stephen G4SJP
> >
> > On Wednesday, 9 May 2012, Fred Jensen wrote:
> >
> >> I haven't been following this thread closely but has anyone mentioned a
> >> small magnetic loop like the Alex-Loop? I've got a good SOTA friend who
> >> uses one and loves it.
> >>
> >> 73,
> >>
> >> Fred K6DGW
> >> - Northern California Contest Club
> >> - CU in the 2012 Cal QSO Party 6-7 Oct 2012
> >> - www.cqp.org
> ______________________________________________________________
> 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
>

David Cutter

Re: Portable Antennas (mag loop)

I agree about the statement re height above ground which needed
qualifiying a little particularly as they then made measurements
somewhat less than that. The main thrust is about losses and the more
removed from ground and nearby objects the less the loss due to the very
high intensity of the electric field. Not sure if they specified a
maximum power handling and I didn't see anything about inter-plate
insulation so it was just dry air - (ie all the water is frozen on the
ground). That probably also means the ground was not as conductive and
lossy as it might be in the summer when the electrolytes are free to
move (my guesswork). Wouldn't work too well in our wet UK climate!
Great piece of analysis and engineering, deceptively simple.

David
G3UNA

On 10/05/2012 11:11, Arthur Burke wrote:

> I bookmarked the site - thank you. However, I didn't get very far the
> first time when I saw the comment "....must be 1/2 wavelength above
> the ground..."
> Still would like to go back and review the entire article.
> Brings back a humorous dialog from years ago. One ham expressed the
> desire to build a "....good, but short, 40 meter beam..." It was
> suggested he shorten the beam until it was ultimately a 50-ohm
> resistor of sufficient girth to accept reasonable power levels.
> Chuckles followed.
> Then, someone who apparently didn't pick up on the tongue-in-cheek,
> frowned and noted that the 50-ohm resistor would work even better if
> it was at least a couple wavelengths in the air.
> Art - N4PJ
>
>
> On Thu, May 10, 2012 at 7:30 AM, David Cutter <[hidden email]
> <mailto:[hidden email]>> wrote:
>
> It will be quiet on receive and quiet on transmit, however much power
> you put into it, until it melts, that is. I'd love to know where he
> gets his efficiency figures - perhaps you can ask him. Putting steel
> washers at each aluminium joint turned me off completely along
> with the
> dinky receiving capacitor.
>
> I'm quite taken by the Midnight Loop from N2APB and N2CX, mainly
> because
> I built something similar 20 years ago, only a lot bigger! See
>
> http://www.midnightdesignsolutions.com/MidnightLoop/Midnight%20Loop%20%28Mar%2011a%29.pdf
>
> David
> G3UNA
>
>
> On 10/05/2012 07:55, Stephen Prior wrote:
> > Hi Fred
> >
> > I have been very tempted by the Alex-loop, but in the meantime
> have just
> > bought one of G4TPH's loops which I shall put through its paces
> when the
> > weather improves! I should imagine that the insensitivity to
> electric
> > fields in the near field would be an advantage in electrically noisy
> > environments. Even a campsite can be very noisy with the
> inverters from RVs
> > and the like spewing out rf everywhere.
> >
> > I'm spoilt for choice of antennas to play with once the KX3 arrives!
> >
> > 73 Stephen G4SJP
> >
> > On Wednesday, 9 May 2012, Fred Jensen wrote:
> >
> >> I haven't been following this thread closely but has anyone
> mentioned a
> >> small magnetic loop like the Alex-Loop? I've got a good SOTA
> friend who
> >> uses one and loves it.
> >>
> >> 73,
> >>
> >> Fred K6DGW
> >> - Northern California Contest Club
> >> - CU in the 2012 Cal QSO Party 6-7 Oct 2012
> >> - www.cqp.org <http://www.cqp.org/>
> ______________________________________________________________
> 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 <http://www.qsl.net/>
> Please help support this email list: http://www.qsl.net/donate.html
>
>

Arthur Burke

Re: Portable Antennas (mag loop)

I have a small magnetic loop that's used strictly for receiving. It's a
Pixel loop with a preamp (from the same company) and I was astounded at how
well it works. I located it about 10 feet up on a rotor, about 50 feet away
from the house. It is incredibly broadbanded. While it doesn't quite hear
what my K3 hears, it hears surprisingly well across a pretty wide spectrum.
I use it mostly for broadcast band DXing, but it also does a pretty good
job of keeping track of the county hunter CW net frequencies (40M, 30M and
20M).

The loop is only about 3-feet in diameter - sells for around $400, which
included the preamp. The preamp has a switching mechanism I connected to
the PTT off our rigs (I share the shack with my wife, who is N4BU).
Anything in the shack that trips the ARB-704 relay shuts off the preamp so
it doesn't get fried.

Art - N4PJ

On Thu, May 10, 2012 at 9:10 AM, David Cutter <[hidden email]> wrote:

> I agree about the statement re height above ground which needed
> qualifiying a little particularly as they then made measurements somewhat
> less than that. The main thrust is about losses and the more removed from
> ground and nearby objects the less the loss due to the very high intensity
> of the electric field. Not sure if they specified a maximum power handling
> and I didn't see anything about inter-plate insulation so it was just dry
> air - (ie all the water is frozen on the ground). That probably also means
> the ground was not as conductive and lossy as it might be in the summer
> when the electrolytes are free to move (my guesswork). Wouldn't work too
> well in our wet UK climate! Great piece of analysis and engineering,
> deceptively simple.
>
> David
> G3UNA
>
> On 10/05/2012 11:11, Arthur Burke wrote:
>
> I bookmarked the site - thank you. However, I didn't get very far the
> first time when I saw the comment "....must be 1/2 wavelength above the
> ground..."
>
> Still would like to go back and review the entire article.
>
> Brings back a humorous dialog from years ago. One ham expressed the desire
> to build a "....good, but short, 40 meter beam..." It was suggested he
> shorten the beam until it was ultimately a 50-ohm resistor of sufficient
> girth to accept reasonable power levels. Chuckles followed.
>
> Then, someone who apparently didn't pick up on the tongue-in-cheek,
> frowned and noted that the 50-ohm resistor would work even better if it was
> at least a couple wavelengths in the air.
>
> Art - N4PJ
>
>
>
> On Thu, May 10, 2012 at 7:30 AM, David Cutter <[hidden email]>wrote:
>
>> It will be quiet on receive and quiet on transmit, however much power
>> you put into it, until it melts, that is. I'd love to know where he
>> gets his efficiency figures - perhaps you can ask him. Putting steel
>> washers at each aluminium joint turned me off completely along with the
>> dinky receiving capacitor.
>>
>> I'm quite taken by the Midnight Loop from N2APB and N2CX, mainly because
>> I built something similar 20 years ago, only a lot bigger! See
>>
>>
>> http://www.midnightdesignsolutions.com/MidnightLoop/Midnight%20Loop%20%28Mar%2011a%29.pdf
>>
>> David
>> G3UNA
>>
>>
>> On 10/05/2012 07:55, Stephen Prior wrote:
>> > Hi Fred
>> >
>> > I have been very tempted by the Alex-loop, but in the meantime have just
>> > bought one of G4TPH's loops which I shall put through its paces when the
>> > weather improves! I should imagine that the insensitivity to electric
>> > fields in the near field would be an advantage in electrically noisy
>> > environments. Even a campsite can be very noisy with the inverters from
>> RVs
>> > and the like spewing out rf everywhere.
>> >
>> > I'm spoilt for choice of antennas to play with once the KX3 arrives!
>> >
>> > 73 Stephen G4SJP
>> >
>> > On Wednesday, 9 May 2012, Fred Jensen wrote:
>> >
>> >> I haven't been following this thread closely but has anyone mentioned a
>> >> small magnetic loop like the Alex-Loop? I've got a good SOTA friend
>> who
>> >> uses one and loves it.
>> >>
>> >> 73,
>> >>
>> >> Fred K6DGW
>> >> - Northern California Contest Club
>> >> - CU in the 2012 Cal QSO Party 6-7 Oct 2012
>> >> - www.cqp.org
>> ______________________________________________________________
>> 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
>>
>
>

Hisashi T Fujinaka

Re: Portable Antennas (mag loop)

In reply to this post by David Cutter

It was presented at a QRP conference, after all (and I'm more of a QRO
proponent) so I imagine the dinky capacitor didn't worry them too much.

My MFJ loop is working pretty darn well so far. I'm sure I'll have to
take it down and fix it eventually, but I have 54 countries worked this
year since I put it up in March.

On Thu, 10 May 2012, David Cutter wrote:

> I agree about the statement re height above ground which needed
> qualifiying a little particularly as they then made measurements
> somewhat less than that. The main thrust is about losses and the more
> removed from ground and nearby objects the less the loss due to the very
> high intensity of the electric field. Not sure if they specified a
> maximum power handling and I didn't see anything about inter-plate
> insulation so it was just dry air - (ie all the water is frozen on the
> ground). That probably also means the ground was not as conductive and
> lossy as it might be in the summer when the electrolytes are free to
> move (my guesswork). Wouldn't work too well in our wet UK climate!
> Great piece of analysis and engineering, deceptively simple.
>
> David
> G3UNA
>
> On 10/05/2012 11:11, Arthur Burke wrote:
>> I bookmarked the site - thank you. However, I didn't get very far the
>> first time when I saw the comment "....must be 1/2 wavelength above
>> the ground..."
>> Still would like to go back and review the entire article.
>> Brings back a humorous dialog from years ago. One ham expressed the
>> desire to build a "....good, but short, 40 meter beam..." It was
>> suggested he shorten the beam until it was ultimately a 50-ohm
>> resistor of sufficient girth to accept reasonable power levels.
>> Chuckles followed.
>> Then, someone who apparently didn't pick up on the tongue-in-cheek,
>> frowned and noted that the 50-ohm resistor would work even better if
>> it was at least a couple wavelengths in the air.
>> Art - N4PJ
>>
>>
>> On Thu, May 10, 2012 at 7:30 AM, David Cutter <[hidden email]
>> <mailto:[hidden email]>> wrote:
>>
>> It will be quiet on receive and quiet on transmit, however much power
>> you put into it, until it melts, that is. I'd love to know where he
>> gets his efficiency figures - perhaps you can ask him. Putting steel
>> washers at each aluminium joint turned me off completely along
>> with the
>> dinky receiving capacitor.
>>
>> I'm quite taken by the Midnight Loop from N2APB and N2CX, mainly
>> because
>> I built something similar 20 years ago, only a lot bigger! See
>>
>> http://www.midnightdesignsolutions.com/MidnightLoop/Midnight%20Loop%20%28Mar%2011a%29.pdf
>>
>> David
>> G3UNA
>>
>>
>> On 10/05/2012 07:55, Stephen Prior wrote:
>> > Hi Fred
>> >
>> > I have been very tempted by the Alex-loop, but in the meantime
>> have just
>> > bought one of G4TPH's loops which I shall put through its paces
>> when the
>> > weather improves! I should imagine that the insensitivity to
>> electric
>> > fields in the near field would be an advantage in electrically noisy
>> > environments. Even a campsite can be very noisy with the
>> inverters from RVs
>> > and the like spewing out rf everywhere.
>> >
>> > I'm spoilt for choice of antennas to play with once the KX3 arrives!
>> >
>> > 73 Stephen G4SJP
>> >
>> > On Wednesday, 9 May 2012, Fred Jensen wrote:
>> >
>> >> I haven't been following this thread closely but has anyone
>> mentioned a
>> >> small magnetic loop like the Alex-Loop? I've got a good SOTA
>> friend who
>> >> uses one and loves it.
>> >>
>> >> 73,
>> >>
>> >> Fred K6DGW
>> >> - Northern California Contest Club
>> >> - CU in the 2012 Cal QSO Party 6-7 Oct 2012
>> >> - www.cqp.org <http://www.cqp.org/>
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
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>> <mailto:[hidden email]>
>>
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>>
>>
> ______________________________________________________________
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--
Hisashi T Fujinaka - [hidden email]
BSEE(6/86) + BSChem(3/95) + BAEnglish(8/95) + MSCS(8/03) + $2.50 = latte
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va3bxg

Re: Portable Antennas (near end fed)

In reply to this post by Stephen G4SJP

I for one am in a quandary on what to get at dayton

A buddipole, alex loop, or g4tph. Being a road warrior, need a good working interior (most times hotel rooms are not accessible to the outside) portable.

And a partridge in a pear tree as well :-)
Robert

a 'kosher' ham
Sent from my BlackBerry device

-----Original Message-----
From: Stephen Prior <[hidden email]>
Sender: [hidden email]
Date: Thu, 10 May 2012 08:55:54
To: [hidden email]<[hidden email]>
Cc: [hidden email]<[hidden email]>
Subject: Re: [Elecraft] Portable Antennas (near end fed)

Hi Fred

I have been very tempted by the Alex-loop, but in the meantime have just
bought one of G4TPH's loops which I shall put through its paces when the
weather improves! I should imagine that the insensitivity to electric
fields in the near field would be an advantage in electrically noisy
environments. Even a campsite can be very noisy with the inverters from RVs
and the like spewing out rf everywhere.

I'm spoilt for choice of antennas to play with once the KX3 arrives!

73 Stephen G4SJP

On Wednesday, 9 May 2012, Fred Jensen wrote:

Mike Markowski-2

Re: Non-portable Antenna (roof)

Not a portable solution but an interesting story is that a friend here at
Aberdeen Proving Ground, MD had the same concerns and by chance was assigned a
top floor room in barracks. It turns out his window frame is connected to a
metal shroud wrapping around the bldg, and the shroud is connected to metal
roof. His 1-band 40m qrp rig tunes up and he's making qsos on it at 5W!

73,
Mike ab3ap

On 05/11/2012 11:16 AM, [hidden email] wrote:
> I for one am in a quandary on what to get at dayton
>
> A buddipole, alex loop, or g4tph. Being a road warrior, need a good working
> interior (most times hotel rooms are not accessible to the outside)
> portable.
>
> And a partridge in a pear tree as well :-) Robert
>
> a 'kosher' ham Sent from my BlackBerry device
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Mike WA8BXN

Re: Portable Antennas (near end fed)

In reply to this post by va3bxg

I too would like to hear the answers to this question! But I have an added
question and thought. What are reasonable expectations to being able to work
much with an in the motel room antenna? I would expect a lot of noise, a lot
of shielding and need to use 40 or 80a meters at night which is rougher to
do with short antennas. My approach would be Internet access to a rig at
home.

The thought is that one could test out indoor antennas in their own shack to
see how various things work. Second thought, particularly with respect to
small loops, I wonder if they would be useful to home use (primarily as a
receive antenna assuming the presence of better outside antennas for
transmitting) being easy to rotate by hand to try to null noise or QRM.

73 - Mike WA8BXN

-------Original Message-------

From: [hidden email]
Date: 5/11/2012 11:27:40 AM
To: [hidden email]; [hidden email]
Cc: Elecraft list
Subject: Re: [Elecraft] Portable Antennas (near end fed)

I for one am in a quandary on what to get at Dayton

A buddipole, Alex loop, or g4tph. Being a road warrior, need a good working
interior (most times hotel rooms are not accessible to the outside) portable

And a partridge in a pear tree as well :-)
Robert

A 'kosher' ham
Sent from my BlackBerry device

-----Original Message-----
From: Stephen Prior <[hidden email]>
Sender: [hidden email]
Date: Thu, 10 May 2012 08:55:54
To: [hidden email]<[hidden email]>
Cc: [hidden email]<[hidden email]>
Subject: Re: [Elecraft] Portable Antennas (near end fed)

Hi Fred

I have been very tempted by the Alex-loop, but in the meantime have just
Bought one of G4TPH's loops which I shall put through its paces when the
Weather improves! I should imagine that the insensitivity to electric
Fields in the near field would be an advantage in electrically noisy
Environments. Even a campsite can be very noisy with the inverters from RVs
And the like spewing out rf everywhere.

I'm spoilt for choice of antennas to play with once the KX3 arrives!

73 Stephen G4SJP

On Wednesday, 9 May 2012, Fred Jensen wrote:

--
Sent from Gmail Mobile
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David Cutter

Re: Non-portable Antenna (roof)

In reply to this post by Mike Markowski-2

That sounds really cool. How does he make connection?

David
G3UNA

On 11/05/2012 15:47, Mike Markowski wrote:

> Not a portable solution but an interesting story is that a friend here at
> Aberdeen Proving Ground, MD had the same concerns and by chance was assigned a
> top floor room in barracks. It turns out his window frame is connected to a
> metal shroud wrapping around the bldg, and the shroud is connected to metal
> roof. His 1-band 40m qrp rig tunes up and he's making qsos on it at 5W!
>
> 73,
> Mike ab3ap
>
> On 05/11/2012 11:16 AM, [hidden email] wrote:
>> I for one am in a quandary on what to get at dayton
>>
>> A buddipole, alex loop, or g4tph. Being a road warrior, need a good working
>> interior (most times hotel rooms are not accessible to the outside)
>> portable.
>>
>> And a partridge in a pear tree as well :-) Robert
>>
>> a 'kosher' ham Sent from my BlackBerry device
> ______________________________________________________________
> 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
>

David Cutter

Re: Portable Antennas (near end fed)

In reply to this post by va3bxg

I wouldn't buy a loop. IF you only have those 3 choices, I would go for
the Buddipole, but I'm sure there must be other choices out there, I
don't like spending a lot of money on antennas unless it offers
something really special. Have you seen the Bravo?

See http://n6bt.com/n6bt-Bravo-dayton-faq-1.htm

Not sure if it would fit inside your hotel bedroom.

David
G3UNA

On 11/05/2012 15:16, [hidden email] wrote:

> I for one am in a quandary on what to get at dayton
>
> A buddipole, alex loop, or g4tph. Being a road warrior, need a good working interior (most times hotel rooms are not accessible to the outside) portable.
>
> And a partridge in a pear tree as well :-)
> Robert
>
> a 'kosher' ham
> Sent from my BlackBerry device
>

Vic Rosenthal

Re: Portable Antennas (near end fed)

In reply to this post by Mike WA8BXN

Every time I've tried this, results have been poor. There is so much electrical wiring,
fluorescent lights and and other devices nearby that noise is awful. Bigger hotels are
often built with reinforced concrete, etc. A balcony or openable window is the best choice.

On 5/11/2012 9:09 AM, Mike WA8BXN wrote:

>
>
> I too would like to hear the answers to this question! But I have an added
> question and thought. What are reasonable expectations to being able to work
> much with an in the motel room antenna? I would expect a lot of noise, a lot
> of shielding and need to use 40 or 80a meters at night which is rougher to
> do with short antennas. My approach would be Internet access to a rig at
> home.
>
> The thought is that one could test out indoor antennas in their own shack to
> see how various things work. Second thought, particularly with respect to
> small loops, I wonder if they would be useful to home use (primarily as a
> receive antenna assuming the presence of better outside antennas for
> transmitting) being easy to rotate by hand to try to null noise or QRM.
>
> 73 - Mike WA8BXN

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

Re: Portable Antennas (near end fed)

In reply to this post by Mike WA8BXN

I think you've hit the nail on the head: couple your K series to the
internet using a decent outdoor aerial at home. Spend your money for
effective communication and avoid all those nasty emc troubles in hotel
rooms, unless you can poke a wire out of the window. BTW, you probably
need permission from the hotel owner to do this.

Loops are good for receiving using an external amplifier if you need
to. You can get very good nulling of nearby noise sources. You only
need simple wire loops, no fancy hardware.

David
G3UNA

On 11/05/2012 16:09, Mike WA8BXN wrote:

>
> I too would like to hear the answers to this question! But I have an added
> question and thought. What are reasonable expectations to being able to work
> much with an in the motel room antenna? I would expect a lot of noise, a lot
> of shielding and need to use 40 or 80a meters at night which is rougher to
> do with short antennas. My approach would be Internet access to a rig at
> home.
>
> The thought is that one could test out indoor antennas in their own shack to
> see how various things work. Second thought, particularly with respect to
> small loops, I wonder if they would be useful to home use (primarily as a
> receive antenna assuming the presence of better outside antennas for
> transmitting) being easy to rotate by hand to try to null noise or QRM.
>
> 73 - Mike WA8BXN

Mike Markowski-2

Re: Non-portable Antenna (roof)

In reply to this post by David Cutter

He uses an alligator clip to the metal handle that opens window, and said he
almost fell over when someone answered his first CQ. :-)

73,
Mike ab3ap

On 05/11/2012 12:58 PM, David Cutter wrote:

> That sounds really cool. How does he make connection?
>
> David
> G3UNA
>
> On 11/05/2012 15:47, Mike Markowski wrote:
>> Not a portable solution but an interesting story is that a friend here at
>> Aberdeen Proving Ground, MD had the same concerns and by chance was assigned a
>> top floor room in barracks. It turns out his window frame is connected to a
>> metal shroud wrapping around the bldg, and the shroud is connected to metal
>> roof. His 1-band 40m qrp rig tunes up and he's making qsos on it at 5W!
>>
>> 73,
>> Mike ab3ap
>>
>> On 05/11/2012 11:16 AM, [hidden email] wrote:
>>> I for one am in a quandary on what to get at dayton
>>>
>>> A buddipole, alex loop, or g4tph. Being a road warrior, need a good working
>>> interior (most times hotel rooms are not accessible to the outside)
>>> portable.
>>>
>>> And a partridge in a pear tree as well :-) Robert
>>>
>>> a 'kosher' ham Sent from my BlackBerry device
>> ______________________________________________________________
>> 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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> Home: http://mailman.qth.net/mailman/listinfo/elecraft
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> Post: mailto:[hidden email]
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123