I'm surprised you're burning the tree at only 30' from the feed point. I
wouldn't be surprised at a quarter wavelength out but 30' on 160 meters is
maybe .05 wavelength out or something. Should be high current, relatively low
voltage. I'm doing this in my head which is not a reliable way to do
calculations.
Ham lore around here is trees matter at high voltage points not current points.
This may just be of those things we know that isn't true.
Maybe you aren't exclusively QRP.
Jon
On Jul 29, 2013, at 8:20 AM, Bob McGraw - K4TAX wrote:
> One end of my 160M antenna being #12 hard drawn copper, about 30 ft from the
> feed point runs through the top of a Maple tree. The only thing I've noticed
> is the leaves and limbs burnt at the point the wire contacts the tree.
> {Saves the cost of a tree triming service.} Wind, snow, ice and rain have
> little to no effect on the operation.
>
> As Will Rodgers said "it's not what folks know that concerns me, it's what
> folks know that isn't correct, that gives concern". This I find to be
> largely true with baluns and openwire line and balanced line.
>
> 73
> Bob, K4TAX
>
>
>
>
> ----- Original Message ----- From: "Phil Sussman" <psussman@pactor.com>
> To: "Scott Harwood" <scotthsr@earthlink.net>; "Discussion of Ten-Tec
> Equipment" <tentec@contesting.com>
> Sent: Monday, July 29, 2013 8:20 AM
> Subject: Re: [TenTec] OT: Openwire/Window Line and Bad Wx
>
>
>> I also use openwire feeder with 4" spacing. Rain, snow, ice, wind, hot, cool,
>> the tuner usually doesn't have to be adjusted. (Unless it's unusually hot or
>> cold)
>>
>> 73 de Phil - N8PS
>>
>> PS. I agree with Scott. I had a tree limb brushing the wire antenna and I
>> didn't notice it -- until my XYL pointed it out. Seemed to have no effect,
>> however.
>>
>> ---
>>
>> Quoting Scott Harwood <scotthsr@earthlink.net>:
>>
>>> That was a great article. I'm a huge fan of open wire also.
>>>
>>> Last year I had a contractor doing some work in my side yard and he
>>> actually tied back my open wire line to an aluminum gutter using plastic
>>> cable ties. I did notice I had to re-tune one day, but the guys I talk to
>>> on 75 meters said my signal had been as strong as usual! I didn't
>>> discover the tied down line until a week later while checking out his work
>>> in the yard. Go figure.
>>>
>>> Scott K4VWK
>>>
>>>
>>> -----Original Message-----
>>>> From: Rick - DJ0IP / NJ0IP <Rick@DJ0IP.de>
>>>> Sent: Jul 29, 2013 4:54 AM
>>>> To: 'Discussion of Ten-Tec Equipment' <tentec@contesting.com>
>>>> Subject: [TenTec] OT: Openwire/Window Line and Bad Wx
>>>>
>>>> I extracted this topic from the other thread on the Model 238.
>>>>
>>>> How does bad weather affect openwire compared to its effect on window line?
>>>> Lots of opinions, lots of myths.
>>>>
>>>> Bob Allison (WB1CGM) and Joel Hallas (W1ZR) tested this to find out.
>>>> Their results are reported in the November 2009 issue of QST on page 66.
>>>> See: http://www.dj0ip.de/spiderbeam-1/spiderpole/pole-base-mount/ and then
>>>> select "W1ZR" as author and "2009" as year.
>>>> Unfortunately you have to be a member of ARRL to download this and it is
>>>> copyrighted, otherwise I would post the download on my web.
>>>>
>>>> Summary, for 95 ft. of feedline (the length they tested), the change is
>>>> negligible in both.
>>>> It is ever so slightly worse with window line, but less than 0.2dB.
>>>> NEGLIGIBLE!
>>>>
>>>> The real difference is, true openwire changes it impedance only slightly
>>>> when wet, whereas the window line changes more and generally requires
>>>> re-tuning the matchbox.
>>>>
>>>> One word of caution, which should be obvious: Neither are suitable for
>>>> running along the ground, whether wet or dry!
>>>>
>>>> Being an operwire fanatic, I personally found this to be one of the most
>>>> useful articles ever published in QST.
>>>>
>>>> 73
>>>> Rick, DJ0IP
>>>>
>>>>
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>>>
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>>
>>
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