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KX3 Field Ant. for 80/40/30

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JT Croteau-3

KX3 Field Ant. for 80/40/30

Friends, what would be a good end fed wire setup that will match well
with the internal KX3 ATU and cover, hopefully, 80, 40, and 30 meters?

I went out to my winter camp site, with two really tall pine trees,
and tried to experiment with a 9:1 UNUN, 135' radiator, and 35' of
RG8X. It was a total disaster. Best matches were on 20, 17, and 15
meters but only with 6.4:1 SWR. No match at all on the lower bands.
With my two trees, the radiator made for a perfect inverted-L shape.

What should I try next? I did try some pruning of the antenna but
quickly gave up due to the WX conditions.

Thanks
N1ESE
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Don Wilhelm

Re: KX3 Field Ant. for 80/40/30

The easiest end fed antenna for portable use with those bands on the
KX2/KX3 comes from some experiments and experience of one of the KX2
field testers (and an active SOTA ham).
Use a BNC to dual binding post (Pomona) adapter on the KX2/3. Connect a
58 foot piece of wire to the red (center conductor) post, and a 23 foot
"counterpoise" wire to the black (shield) post. The counterpoise wire
can be run along the ground or laying on top of nearby bushes.
Tie a rock or other throwing item to the end of the 58 foot radiator and
get it up in the air - TUNE it and operate.
No balun, no fuss, and the wire rolls up into a small ball for transport.

73,
Don W3FPR

On 11/18/2017 4:34 PM, JT Croteau wrote:
> Friends, what would be a good end fed wire setup that will match well
> with the internal KX3 ATU and cover, hopefully, 80, 40, and 30 meters?
>
> I went out to my winter camp site, with two really tall pine trees,
> and tried to experiment with a 9:1 UNUN, 135' radiator, and 35' of
> RG8X. It was a total disaster. Best matches were on 20, 17, and 15
> meters but only with 6.4:1 SWR. No match at all on the lower bands.
> With my two trees, the radiator made for a perfect inverted-L shape.
>
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Jim Brown-10

Re: KX3 Field Ant. for 80/40/30

In reply to this post by JT Croteau-3

On 11/18/2017 1:34 PM, JT Croteau wrote:
> Friends, what would be a good end fed wire setup that will match well
> with the internal KX3 ATU and cover, hopefully, 80, 40, and 30 meters?
>
> I went out to my winter camp site, with two really tall pine trees,
> and tried to experiment with a 9:1 UNUN, 135' radiator, and 35' of
> RG8X.

The ARRL Handbook and ARRL Antenna Book are your friend. If you don't
own them, RUN to your computer and buy one, new or used.

The short answer to your question is that, in general, end-fed wires
need a counterpoise to work well. For your situation, I'd build two
end-fed center-fed dipoles, one for 80 and one for 40, launch one into
one of the trees, the second into the other tree. 75 ohm coax is the
best match to these antennas, but 50 ohm coax will work. The following
slide show describes this technique, beginning on slide #70.

http://k9yc.com/VerticalHeight.pdf

If possible, rig your dipoles so that they slope away from the tree(s)
in which they are mounted. Anecdotal reports, and my limited experience,
say that trees absorb a bit of the RF from a wire very close to their
trunk. I suggest that you pull both antennas up as high as practical.

If for some reason you don't want to rig a dipole like this, pull a
quarter wave wire for both bands into those trees and rig a quarter-wave
counterpoise for each that's at least 6-8 ft above ground. If a feedline
is needed, use RG8X with a good common mode choke but no transformer.

73, Jim K9YC

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JT Croteau-3

Re: KX3 Field Ant. for 80/40/30

In reply to this post by Don Wilhelm

Thanks Don, I will try this next.

On Sat, Nov 18, 2017 at 5:05 PM, Don Wilhelm <[hidden email]> wrote:

> The easiest end fed antenna for portable use with those bands on the KX2/KX3
> comes from some experiments and experience of one of the KX2 field testers
> (and an active SOTA ham).
> Use a BNC to dual binding post (Pomona) adapter on the KX2/3. Connect a 58
> foot piece of wire to the red (center conductor) post, and a 23 foot
> "counterpoise" wire to the black (shield) post. The counterpoise wire can
> be run along the ground or laying on top of nearby bushes.
> Tie a rock or other throwing item to the end of the 58 foot radiator and get
> it up in the air - TUNE it and operate.
> No balun, no fuss, and the wire rolls up into a small ball for transport.
>
> 73,
> Don W3FPR
>
>
> On 11/18/2017 4:34 PM, JT Croteau wrote:
>>
>> Friends, what would be a good end fed wire setup that will match well
>> with the internal KX3 ATU and cover, hopefully, 80, 40, and 30 meters?
>>
>> I went out to my winter camp site, with two really tall pine trees,
>> and tried to experiment with a 9:1 UNUN, 135' radiator, and 35' of
>> RG8X. It was a total disaster. Best matches were on 20, 17, and 15
>> meters but only with 6.4:1 SWR. No match at all on the lower bands.
>> With my two trees, the radiator made for a perfect inverted-L shape.
>>
>

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Erlend Grimseid

Re: KX3 Field Ant. for 80/40/30

In reply to this post by JT Croteau-3

Hi.
Feet is not my everyday system for length measure, but i think it
transelate to very close to an full wave length on 40m and close to an half
wave on 80. That is an tough match for any tuner. Even so, with the
transformer and the coax I think it should have given better results than
6.4:1 on most bands.

Did you have an choke between the coax and the radio/tuner? That might be
worth a try. Also I would look for malfunction somewhere.

BUT. To answer your question. My go to antenna for the lower bands is an
simple dublet, feed with some old army field telephone wire. It's an
twisted pair of multi strand wire. I belive it has four strands of copper,
ant three stainless steel, but I might be mistaken. The dublet is 2x20 (
aprox) meters. Might be worth a try.

La4tta Erlend

18. nov. 2017 10:37 p.m. skrev "JT Croteau" <[hidden email]>:

Friends, what would be a good end fed wire setup that will match well
with the internal KX3 ATU and cover, hopefully, 80, 40, and 30 meters?

I went out to my winter camp site, with two really tall pine trees,
and tried to experiment with a 9:1 UNUN, 135' radiator, and 35' of
RG8X. It was a total disaster. Best matches were on 20, 17, and 15
meters but only with 6.4:1 SWR. No match at all on the lower bands.
With my two trees, the radiator made for a perfect inverted-L shape.

What should I try next? I did try some pruning of the antenna but
quickly gave up due to the WX conditions.

Thanks
N1ESE
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Jim Brown-10

Re: KX3 Field Ant. for 80/40/30

In reply to this post by Don Wilhelm

Yes, this is also a great technique. One suggestion though -- there's RF
current in the counterpoise, and having it too close to the ground will
burn (waste) some TX power. Better to run it in the range of 6-8 ft.

Remember - an SWR indication at the rig is NOT an indicator of antenna
performance. It only tells us that the transmitter is matched to
whatever is connected to its terminals, but it tells us nothing about
how much power is LOST in the feedline, the antenna, or the ground, nor
does it tell us how well the antenna radiates or in what directions
(vertically and horizontally) it radiates.

73, Jim K9YC

On 11/18/2017 2:05 PM, Don Wilhelm wrote:

> The easiest end fed antenna for portable use with those bands on the
> KX2/KX3 comes from some experiments and experience of one of the KX2
> field testers (and an active SOTA ham).
> Use a BNC to dual binding post (Pomona) adapter on the KX2/3. Connect
> a 58 foot piece of wire to the red (center conductor) post, and a 23
> foot "counterpoise" wire to the black (shield) post. The counterpoise
> wire can be run along the ground or laying on top of nearby bushes.
> Tie a rock or other throwing item to the end of the 58 foot radiator
> and get it up in the air - TUNE it and operate.
> No balun, no fuss, and the wire rolls up into a small ball for transport.

k6dgw

Re: KX3 Field Ant. for 80/40/30

In reply to this post by JT Croteau-3

My HOA-Stealth antenna is the "80-10 EF" from myantennas.com It is
strung on electric fence insulators along the top of the wooden fence,
about 1.8 meters high. It has a 90 deg bend in it about 1/3 of the way
down from the transformer. It actually works 160-10 with my K3/100 +
KAT3. It works surprisingly well, so much so that I bought a second to
take on county expeditions in the 7QP contest. I took First in Pershing
County this year with ~350 CW-only Q's. While that is also "Last in
Pershing County," that is not indicated on the certificate. [:-) Next
year I may be First in Lander County, who knows?

Usual Disclaimer: No financial interest in the company

73,

Fred ["Skip"] K6DGW
Sparks NV DM09dn
Washoe County

On 11/18/2017 1:34 PM, JT Croteau wrote:

> Friends, what would be a good end fed wire setup that will match well
> with the internal KX3 ATU and cover, hopefully, 80, 40, and 30 meters?
>
> I went out to my winter camp site, with two really tall pine trees,
> and tried to experiment with a 9:1 UNUN, 135' radiator, and 35' of
> RG8X. It was a total disaster. Best matches were on 20, 17, and 15
> meters but only with 6.4:1 SWR. No match at all on the lower bands.
> With my two trees, the radiator made for a perfect inverted-L shape.
>
> What should I try next? I did try some pruning of the antenna but
> quickly gave up due to the WX conditions.
>
> Thanks
> N1ESE
>

Terry Myers

KX3 Field Ant. for 80/40/30

Why not do Nye county as well. That might only take one QSO. hi-hi

Terry, KQ5U

On 11/18/2017 4:29 PM, Fred Jensen wrote:

> My HOA-Stealth antenna is the "80-10 EF" from myantennas.com It is
> strung on electric fence insulators along the top of the wooden fence,
> about 1.8 meters high. It has a 90 deg bend in it about 1/3 of the
> way down from the transformer. It actually works 160-10 with my
> K3/100 + KAT3. It works surprisingly well, so much so that I bought a
> second to take on county expeditions in the 7QP contest. I took First
> in Pershing County this year with ~350 CW-only Q's. While that is
> also "Last in Pershing County," that is not indicated on the
> certificate. [:-) Next year I may be First in Lander County, who knows?
>
> Usual Disclaimer: No financial interest in the company
>
> 73,
>
> Fred ["Skip"] K6DGW
> Sparks NV DM09dn
> Washoe County
>
> On 11/18/2017 1:34 PM, JT Croteau wrote:
>> Friends, what would be a good end fed wire setup that will match well
>> with the internal KX3 ATU and cover, hopefully, 80, 40, and 30 meters?
>>
>> I went out to my winter camp site, with two really tall pine trees,
>> and tried to experiment with a 9:1 UNUN, 135' radiator, and 35' of
>> RG8X. It was a total disaster. Best matches were on 20, 17, and 15
>> meters but only with 6.4:1 SWR. No match at all on the lower bands.
>> With my two trees, the radiator made for a perfect inverted-L shape.
>>
>> What should I try next? I did try some pruning of the antenna but
>> quickly gave up due to the WX conditions.
>>
>> Thanks
>> N1ESE
>>
>
> ______________________________________________________________
> Elecraft mailing list
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>
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> Please help support this email list: http://www.qsl.net/donate.html
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k6dgw

Re: KX3 Field Ant. for 80/40/30

Nearest "town" for me in Nye County is Gabbs, population 269, about 2.5
hrs from home. I'm way too old and way too physically diminished to do
this without reasonable accommodations. Google Nye County NV and pick
Wikipedia for a photo of "downtown" Gabbs. Between home and Gabbs is a
whole lot of Basin and Range and no people. Might consider Lander Co
from Battle Mountain however.

73,

Fred ["Skip"] K6DGW
Sparks NV DM09dn
Washoe County

On 11/18/2017 3:45 PM, Terry wrote:
> Why not do Nye county as well. That might only take one QSO. hi-hi
>
> Terry, KQ5U

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Jim Brown-10

Re: KX3 Field Ant. for 80/40/30

Check out the expedition that W6GJB, W6JTI, and I did for 7QP last year
(2016) to seven NV counties, including Nye and Lander. k9yc.com/7QP.pdf

73, Jim K9YC

On 11/18/2017 4:52 PM, Fred Jensen wrote:
> Nearest "town" for me in Nye County is Gabbs, population 269, about
> 2.5 hrs from home. I'm way too old and way too physically diminished
> to do this without reasonable accommodations. Google Nye County NV
> and pick Wikipedia for a photo of "downtown" Gabbs. Between home and
> Gabbs is a whole lot of Basin and Range and no people. Might consider
> Lander Co from Battle Mountain however.

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