Tony, no need to fret about drilling. I would say than going under is
better than going over. The crews who do direct burial for cable TV and
fiber have special directional drill attachments that you should try to
borrow. the will go straight down along the wall until they get to the
dirt under the wall, find their way under the wall and come up on the
other side. You just a need a few of these connector and for them it is
something they do all the time under highways, concrete drainage and
sidewalks, as a matter of their work.
If you want to DIY you could also excavate as much as possible on both
sides, take some 8 foot ground rods and drive them at an angle drive
with a sledge on each side and see if you can "establish contact". Fill
both sides of the pilot holes with rock salt, the water them for several
days. Eventually you should have a fairly low resistance connection
from one rod to the other, even if they do not touch. Connect you
radials to both ground rods. Only problem with the rock salt is it will
eventually each away at the copper covered steel rod. But you should be
good for a year or two.
Before I get royally flamed here and subjected to humiliation by not
having this advice peer reviewed, let me suggest that this method has
never been tested by me and probably not by anyone else.
Herb Schoenbohm, KV4FZ
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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