Several years ago in the No Cal DXer I saw where a W6 recommended using 1/2"
copper water pipe with a heart of #4 reinforcing steel (that's 1/2") as an
economical ground rod. Once again the difference between one industry's
method of sizing versus plumbing's pays off.....Ham Inginuity usually seems
to owe thanks to the plumbing world.
Plumbing stuff always has a call size which relates to its inner diameter
(after all that is where the water travels)...so 1/2" plumbing tubing is 1/2"
on the inside. This is akin to when you need a mast and the guys asks you if
you want a pipe or a tube - see W6QHS' book.
#4 Rebar (as in four eighths....aka .5") is about that in its diameter. Voila
the two can "nest".
The local home center sells ten foot lengths of both and a while back Dad
just had them deliver a bunch of both, when a new ground is need one is
slipped inside the other.
Literally a ton of these things are at W1CW, there is an elaborate grounding
system with one of these every 10 or 15 feet, plus ones at the bases of the
towers and the guy points. etc.
The #4 rebar is usually import stuff...its old soup cans from JAs sometimes,
according to the US rebar guys' Pittsburgh propaganda corps. Actually it
seems there is an awful lot of Korean stuff, at least in the FL market.
Some of this imported stuff is not as good as the others as far as
tolerances. Sometimes a sloppy mold will result in the bar being unable to
slip into the tubing. It will be "fuzzy" and slightly oversized making it
unsuitable for this application. Save these pieces for your next offering to
GORF. Obviously a bent rebar ias worthless in this application as well.
When it is right though, it is very slick. You end up getting a ground rod
with a lot more than a mere copper plating's thickness of copper....way lots
more copper.
To drive these things into the hard clay over here in Tampa we use the ideal
weapon....a demolition hammer, with a ground rod driving tip. Yes, they are
made! The tool looks kind of like something Arnold Schwartzenager used in the
Terminator. This is an expensive tool, so we use it a lot to reduce the
average cost per usage....fortunately Dad got one for Christmas a coupla
years back. You can rent these at Taylot or any construction tool rental
place - just make sure you get the bit for the end that is "hollow" for the
ground rod to slide up into. We rented one of these the first time, but
beware: like the first time you used CT for CONTESTING....its one of those
things you won't wanna do without.
This tool is really slick, the machine beats the living **** out of the rebar
and of course its small opposite end is more than glad to drive into the
earth when its rear end is being hammered! The trick is in starting a 10 ft
long rod vertically whilst holding a very heavy three foot long jackhammer
atop it.
Standing near the top of a stepladder, you set the rod and balance the
jackhammer - which has gotta weigh at least 40 pounds - then squeeze the
triger and watch it sink. What is interesting is that leaning on the
jackhammer does not enhance but inhibits driving of the rod....it is best to
let the thing "bounce" away on the end of the rod rather than trying to push
it down.
The QTH at W1CW is very low water table and a lot of the dirt is hard clay,
the slowest rod takes mebbe 10 minutes or so to drive, the faster ones drive
in three or four. Other than hauling that jackhammer up the step ladder it
ain't any work.
I gather from the wet it with a hose gang that this is backwards and
cro-magnon like....but it is also a very manly thing and makes you feel like
grabbing a cold brewsky after you drive one home.
In order to do this properly I recommend you have a sweat stained torn
t-shirt, and a pair of pants which are slightly too small for you - and that
those pants ride a lil' too low....ooops - just say no to crack!
It does work well, and as W0UN points out - it sure is a LOT cheaper than
buying commercial ground rods.
Jim zx k1zx@contesting.com
note: the only draw back is if you are seeking a deep (more than 10 ft)
ground...unlike the screw together commercial jobbies, with these you will be
limitted to the tubings' length.
>From Felipe J. Hernandez" <0006627542@mcimail.com Sat Apr 27 06:34:00 1996
From: Felipe J. Hernandez" <0006627542@mcimail.com (Felipe J. Hernandez)
Subject: Re. This station is or was perfect
Message-ID: <23960427053432/0006627542DC2EM@MCIMAIL.COM>
Hola a todos!
I have to say this, with all the discussions about crap,power
Baffoofnikations and others detrimenting and entertaining subjects,
sometimes we forget about the great experiences that we get from it
As most of you know, I posted a question regarding the perfect location
and I got no less than 40 direct responses, with all kinds of ideas ,
suggestions and new questions and Ill probably wont have the time to answer
each one of them, but Ill like to say that I was amaze with a lot of guys
who introduced themselves as "dummies and Ignorants" came up with great
ideas overlooked by the experts and most important theyre own experiences.
I really want to say thanks to this people and tell them of how great
use the Ideas and suggestions they gave me where to me. So do me a favor
please stop buying the, "whatever for dummies" book series because you
certainly aren't! Thanks again.
Well since a lot of people asked me about the new developments Ive
got good news, a problem was caused when a mistake of the coordenates
was done because the point taken as reference in Pr was done with diff-
erent datums, and thus the actual point was taken in the middle of the
slope so that really messed the actual result, with the new calculations
the site is considerably better.
Tomorrow we are going again to the site with a new TRIMBLE gps and
will do the calculations again and we will post them probably on sunday.
Eric KP4TK is going to write a more technical mail to the reflector with
the latest info. Again thanks for the help and please stay tunned!
Gracias
Felipe
PD. Question... Will scott ka9fox break his record of beers of last year?
Top contenders for the beer record.
1.n0bsh
2.we9v
3.ea3ny
4.wd8ixe yes, you steve.
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