Bob:
Here's a link to a link that has some photos of a shunt feed cage similar
to mine:
http://lists.contesting.com/archives//html/Towertalk/2005-12/msg00643.html.
It's not really a "cage" but Phil has three parallel wires in the same plane
running up the side of his Trylon 72 foot tower, whereas I have two wires (I
had 3 but the 3rd didn't make any difference) running up my 64 ft Trylon tower.
I used heavy cable ties to keep the end and middle of the PVC Ts in place on
the tower. Phil installed an Omega match (two vacuum variable caps) and my
match uses a single series bread slicer cap.
73 de
Gene Smar AD3F
On 12/18/15, Robert Harmon wrote:
Gene,
The cage design sounds very interesting. I just ordered the book :-)
thanks Gene,
Bob
K6UJ
On 12/18/15 9:27 AM, Gene Smar wrote:
> Bob:
>
> I built my shunt feed wire cage based on the design in Jeff Bigg's K1ZM book
> "DXing on the Edge..." I bought it from the ARRL bookstore but you might be
> able to find it on Amazon, etc. I used two widely-spaced wires whereas he
> used three in a triangular form held off the side of his tower with PVC pipe.
> I was surprised at how well it seems to work for me ( I always get through
> and receive good reports.) Good luck.
>
>
> 73 de
> Gene Smar AD3F
>
>
>
>
> On 12/18/15, Robert Harmon wrote:
>
> Stan,
>
> With shunt feed I would gain the 18 foot mast with the yagis, the total
> overall height is 108 feet.
> I haven't really considered shunt feeding. I see your point of the
> wires with an L in proximity to other
> antennas. That was a worry I had with the 40 meter yagi and the L. I
> will look into shunt feeding. I have ON4UN's book, probably should
> start there to bone up. Any other resources to learn abut shunt feeding ?
> The top band archives probably has a lot of discussions about shunt
> feeding also.
>
> thanks Stan,
> Bob
> K6UJ
>
>
>
> On 12/18/15 1:36 AM, Stan Stockton wrote:
>> Bob,
>>
>> There is no reason I can think of to not shunt feed the tower as it is with
>> either ground radials or elevated radials. An inverted L isn't as good as a
>> vertical for DX and you would just be adding clutter and horizontal wires in
>> proximity to your other antennas. Shunt feeding a tower is very, very simple.
>>
>> 73... Stan, K5GO
>>
>>> On Dec 17, 2015, at 8:06 PM, Robert Harmon k6uj@pacbell.net> wrote:
>>>
>>> I am planning an install of a 160M inverted L and would like critique from
>>> you top banders.
>>> I was originally planning a separate tower for 160 but my XYL has squashed
>>> the idea :-)
>>> My tower is 90 feet fully extended with a 18 foot mast currently used for a
>>> Force 12 WARC plus 10/15 beam
>>> on top and a N6BT DXU-32, 2EL 40 and 3EL 20 12 feet below.
>>> At the top of the top section I have a 10 foot fiberglass pole I plan to
>>> extend out to support the vertical, so it will be 10 feet away from the
>>> tower.
>>> I am thinking of feeding the vertical and having 4 elevated radials at the
>>> 14 foot level.
>>> So the vertical wire will about 76 feet long.
>>>
>>> I am wondering if I would be better lowering the feedpoint & radial tie ins
>>> down from 14 feet say to 8 feet and have more length in the vertical
>>> portion of the L or better to have the 14 feet elevation for the radials ?
>>>
>>> Also the horizontal leg of the L on top will be about 5 feet below the
>>> 40/20 yagi only 10 feet out from the tower,
>>> do you think this is OK as far as interaction between the yagi and the 160
>>> L ? Anything else I should consider ?
>>> I have never had a decent 160 antenna, just hoping I can work something out
>>> with my existing situation
>>>
>>> thanks in advance,
>>>
>>> Bob
>>> K6UJ
>>>
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