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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> _________________
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