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End fed antenna - length and SWR

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Esquer Dave

End fed antenna - length and SWR

Hi folks,

Newbie HF Dave here again with an end fed antenna design question.

I have an EARCH (Emergency Amateur Radio Club, Hawaii) end fed 6-40 meter multiband HF antenna. Part of the design is the 9:1 UNUN (unbalanced to unbalanced) toroid matching transformer. I have replaced the 30' wire with 66.5 feet of 18AWG Wireman silky 532. My end fed is in a horizontal (slight slope) orientation, east-west. The antenna is about 50' above the ground (I have a 3 story house and pine trees close by).

I do not have an external antenna analyzer, yet.

Using the ATU in my KX-3, I have the UNTUNED SRW values below. With the KX-3 ATU, the KX-3 DOES tune all of these bands with no problem.

Question: Should I do anything to improve QRP performance, shorten/lengthen the wire, or should I just go with the flow, hang loose and not worry and just enjoy my rig?

REMEMBER, newbie Dave, be gentle. I've been tracking the long wire discussions on the list, there is lots of fervor.

[My key = frequency/SWR]

80m
3.50/2.0
3.752.9
4.0/3.7

40m
7.0/6.9
7.15/6.9
7.3/6.9

20m
14.070/2.9
14.2/2.8
14.35/2.7

15m
21.0/2.8
21.45/3.0

10m
28.0/2.2
29.0/1.8
29.7/2.5

6m
50.0/3.0
52.0/2.3
54.0/3.7

Thanks in advance,
Dave

More static, more of the time …

Dave Esquer, K6WDE
[hidden email]
http://www.daveesquer.com

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kevinr@coho.net

Re: End fed antenna - length and SWR

Hi Dave,
If you want to check in with anyone in Oregon you may want to
change the orientation of your antenna. You are at right angles to the
main land or Asia with that wire the way it is now. There just aren't a
lot of folks north and south of you. Accept geography and try another
direction :)
73,
Kevin. KD5ONS

On 10/8/2013 6:40 PM, Esquer Dave wrote:

> Hi folks,
>
> Newbie HF Dave here again with an end fed antenna design question.
>
> I have an EARCH (Emergency Amateur Radio Club, Hawaii) end fed 6-40 meter multiband HF antenna. Part of the design is the 9:1 UNUN (unbalanced to unbalanced) toroid matching transformer. I have replaced the 30' wire with 66.5 feet of 18AWG Wireman silky 532. My end fed is in a horizontal (slight slope) orientation, east-west. The antenna is about 50' above the ground (I have a 3 story house and pine trees close by).
>
> I do not have an external antenna analyzer, yet.
>
> Using the ATU in my KX-3, I have the UNTUNED SRW values below. With the KX-3 ATU, the KX-3 DOES tune all of these bands with no problem.
>
> Question: Should I do anything to improve QRP performance, shorten/lengthen the wire, or should I just go with the flow, hang loose and not worry and just enjoy my rig?
>
> REMEMBER, newbie Dave, be gentle. I've been tracking the long wire discussions on the list, there is lots of fervor.
>
> [My key = frequency/SWR]
>
> 80m
> 3.50/2.0
> 3.752.9
> 4.0/3.7
>
> 40m
> 7.0/6.9
> 7.15/6.9
> 7.3/6.9
>
> 20m
> 14.070/2.9
> 14.2/2.8
> 14.35/2.7
>
> 15m
> 21.0/2.8
> 21.45/3.0
>
> 10m
> 28.0/2.2
> 29.0/1.8
> 29.7/2.5
>
> 6m
> 50.0/3.0
> 52.0/2.3
> 54.0/3.7
>
> Thanks in advance,
> Dave
>
> More static, more of the time …
>
> Dave Esquer, K6WDE
> [hidden email]
> http://www.daveesquer.com
>
>
> ______________________________________________________________
> 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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Phil Kane-2

Re: End fed antenna - length and SWR

In reply to this post by Esquer Dave

On 10/8/2013 7:58 PM, Ron D'Eau Claire wrote:

> You don't mention a ground/counterpoise. With a 66-foot radiator, that
> becomes important on 40 and substantially more so on 80.

I am using the "stock" HARES antenna. It consists of a 30-ft length of
coax between the antenna tuner and the UNUN and a 30-ft single-wire
end-fed radiator on the "output". Mine runs from the top of my porch -
10 ft above ground - sloping up into a neighboring tree. There is no
counterpoise needed per the instructions for the antenna. The KAT-100
tunes it to a 1:1 SWR on all bands - whether a signal gets out or not. <G>

It can't beat a double extended zepp but it's better than loading a
window frame. It's the best that I can do as a "stealth" antenna to
keep the apartment management happy.

73 de K2ASP - Phil Kane
Elecraft K2/100 s/n 5402

From a Clearing in the Silicon Forest
Beaverton (Washington County) Oregon
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ny4g

Re: End fed antenna - length and SWR

In reply to this post by Esquer Dave

My version using the same matchbox is 44 feet long and tunes well 40 - 6 meters and a piece of cake for the KX3. It is loud on 30m

Ariel NY4G

Sent from my iPhone

On Oct 8, 2013, at 9:40 PM, "Esquer Dave" <[hidden email]> wrote:

Rick Dettinger-3

Re: End fed antenna - length and SWR

I scaled the 44 feet up 4 times to 176 feet to get a reasonable match on 160 meters with my poor ground system.
Its 55 feet high with the rest sloping somewhat down to about 25 feet.
It is tuned at the base with a remote coupler. There is 140 feet of coax berried from the coupler to my 3rd floor (loft) shack.
I am happy with the performance.
Before I built the remote antenna, I had an end fed wire with no coax tuned in the shack. It was fed with a ground wire hanging down the house from the peak. It worked OK on transmit, but was noisy on receive. Getting the feed away from my house really knocked the noise down.

73,
Rick Dettinger K7MW

On Oct 8, 2013, at 8:25 PM, Ariel Jacala wrote:

> My version using the same matchbox is 44 feet long and tunes well 40 - 6 meters and a piece of cake for the KX3. It is loud on 30m
>
> Ariel NY4G
>

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rlindzen

Re: End fed antenna - length and SWR

All these antennas are easy to model with EZNEC. You may find some
of the results surprising.

73, Dick WO1I

At 11:55 PM 10/8/2013, Rick Dettinger wrote:

>I scaled the 44 feet up 4 times to 176 feet to get a reasonable
>match on 160 meters with my poor ground system.
>Its 55 feet high with the rest sloping somewhat down to about 25 feet.
>It is tuned at the base with a remote coupler. There is 140 feet of
>coax berried from the coupler to my 3rd floor (loft) shack.
>I am happy with the performance.
>Before I built the remote antenna, I had an end fed wire with no
>coax tuned in the shack. It was fed with a ground wire hanging down
>the house from the peak. It worked OK on transmit, but was noisy on
>receive. Getting the feed away from my house really knocked the noise down.
>
>73,
>Rick Dettinger K7MW
>
>
>
>
>On Oct 8, 2013, at 8:25 PM, Ariel Jacala wrote:
>
> > My version using the same matchbox is 44 feet long and tunes well
> 40 - 6 meters and a piece of cake for the KX3. It is loud on 30m
> >
> > Ariel NY4G
> >
>
>______________________________________________________________
>Elecraft mailing list
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>
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