Tony,
If snaking one or more wires under the fence isn't feasible, I would
simply run a buss wire around the base of the stone wall to the nearest
opening and then back down the other side. Attach your radials to this
buss wire on the tower side, and the "continuation" of these radials
from the buss wire on the other side. If too far to the nearest opening,
just bore one hole through or under the wall to connect the two buss wires.
Never tested or modeled by me, but I'm doing something similar now with
the four sets of radials on my new broadside-endfire array for Topband.
There are several small drainage ditches (about 3 feet across and a
couple of feet deep) that I didn't want a lot of wires crossing due to
periodic maintenance needs.
73/Jon AA1K
On 8/10/2012 2:21 PM, N2TK, Tony wrote:
> Thanks Bill and Herb about drilling a hole through the wall. That could be
> tough. It is a stone wall with no mortar. It is about 20-28" thick. It is
> well constructed with large field stones. It would be rough to drill through
> all of that. I had thought about taking portion of the wall apart but
> figured I would never get it back to looking as good as it does now. The
> stones go fairly deep so not much chance of going under the wall.
>
> 73,
> N2TK, Tony
>
> -----Original Message-----
> From: Bill Wichers [mailto:billw@waveform.net]
> Sent: Friday, August 10, 2012 12:26 PM
> To: N2TK, Tony; topband
> Subject: RE: Topband: Radials over a stone wall
>
> I would expect an "up and over" to clear the wall would result in a
> choke-like effect on the radial and would, at best, reduce the radial's
> effectiveness.
>
> It should be easy to just drill some small (maybe 1/4"?) holes through the
> wall in a few places to pass the radials through. With a decent hammer drill
> and a carbide bit a small hole like that is pretty quick and easy to
> complete -- even in concrete or stone. Then just use a piece of coathanger
> wire as a wire fishing tool to run the radials through the hole.
>
> I use a wire pulling tool called a "creep-zit" to pull radials under fallen
> trees and logs in the woods. It works great. I basically just take one of
> the 6 foot long fiberglass rods (each of which is a little over 1/8"
> diameter), tape the radial to one end, and then I can push it under fallen
> debris easily. With a little practice you can even get around hidden
> obstructions in the ground this way.
>
> -Bill
>
>
>> I shunt feed my tower for topband. I use variable vacuum caps and a
> vacuum
>> relay at the base to switch between the low end and the high end of
> the
>> band. It seems to work okay. I have 100' buried radials spaced 10' at
> the
>> ends from o degrees going clockwise through about 220 degrees. I have
> a 4'
>> high stone wall that runs about 20/200 degrees that is about 35' at
> its
>> closest point to the tower. So the radials are progressively shorter
> on
>> the
>> West side of the tower.
>>
>>
>>
>> I am making an assumption that going up over the wall will distort any
>> benefits of extending the radials on the West side? Is that a true
>> assumption.
>>
>> I can't really have the radials go from the tower base up at an angle
> to
>> clear the stone wall and continue on. If I am to extend them the
> radials
>> would have to go on the ground to the wall then up and over and back
> down
>> to
>> the ground.
>>
>>
>>
>> 73,
>>
>> N2TK, Tony
>>
>> _______________________________________________
>> UR RST IS ... ... ..9 QSB QSB - hw? BK
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
>
_______________________________________________
UR RST IS ... ... ..9 QSB QSB - hw? BK
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