Hello Steve,
And thanks for the info with which I generally agree.
I might say that with modern wood treatments and adhesives wooden structures
can be made almost everlasting, certainly beyond the life of the builder.
But as we both agree you need to know what you are doing.
Yes, I gave away traps and Force 12 antennas have performed very well for me
here. Not to sure how long the alumaweld linear loading wires will last on
my C-4SXL but have already thought out a fix using fine stranded stainless
steel wire supports with insulated copper wire conductors. The way any
boatie would do it.
73 es tnx again.
Baz
end
Barry Kirkwood PhD ZL1DD
Signal Hill Homestay
66 Cory Road
Palm Beach
Waiheke Island 1240
NEW ZEALAND
www.waiheke.co.nz/signal.htm
----- Original Message -----
From: <K7LXC@aol.com>
To: <bjk@ihug.co.nz>; <towertalk@contesting.com>
Sent: Monday, 19 March, 2001 3:23 AM
Subject: Ten-Year Goal
> In a message dated 3/17/01 11:22:48 PM Pacific Standard Time,
bjk@ihug.co.nz
> writes:
>
> > Quite interesting looking in from the Second World:
> >
> > Attitude seems to be if it is not manufactured you go without.
>
> Not exactly. Here in the States there are many existing products
> available and few reasons to re-invent the wheel. MY point is that when it
> comes to radio towers, you're much better off buying something that's
already
> professionally engineered and manufactured than doing it yourself. I
RARELY
> run into an amateur who can tie a decent knot let alone design and
fabricate
> a proper antenna support. Since a tower is a potentially life and property
> threatening contrivance, I discourage home-brewing of them. (You might
want
> to take a look at my "Ten Most Common Tower Building Mistakes" under Tech
> Notes on our website - <A
HREF="www.championradio.com">www.championradio.com
> </A> - I've worked on over 150 different ham stations and have seen all
the
> mistakes.)
>
> OTOH there are some clever guys who are fully capable of engineering,
> designing and fabricating just about anything. They understand the forces
and
> the realities of their undertaking (no pun intended).
>
> In just about all cases, though, another LXC axiom is to "GO with what
> you've got". In other words, if all you have available is a 30-year
tribander
> and can only get it up 25 feet - go for it. If all you've got is a couple
of
> palm trees or scrap wood or piece of pipe for an antenna support - go for
it.
> Be resourceful but BE SAFE. Just about every DXpedition has to cobble
> together something (sometimes several times) and no one gets killed so it
can
> be done.
>
> But here in the US there's no reason you can't go buy some 4x4 lumber
and
> make a moderate tilt-over wood tower - there are a number of articles from
> the 50's and 60's describing how to do it. You've just got to keep in mind
> that it's going to be up for awhile so you use screws and bolts - not
nails -
> and treated wood so that the danged thing is safe for a number of years
(ten
> is a good number). I'm only trying to discourage un-safe 'hip-pocket
> engineering' by amateurs who are notoriously cheap here in the States and
> can't appreciate or aren't aware of what they're getting into by
home-brewing
> an antenna support.
>
> > Am also amazed by the statement that a an amateur beam antenna system,
> > rotator etc should only need attention every ten years.
>
> My statement was that it's a GOAL. In other words, everything should
be
> done with an eye to the longterm. Let's take a tower. Will a wooden tower
> last ten years? Maybe - maybe not. If you over-engineer it, use screws and
> bolts and treated lumber - your chances of success will increase. Will a
> steel tower last ten years next to saltwater? Maybe - maybe not. But there
> are some things you can do to improve its lifespan; i.e. use of commercial
> coatings on the tower to encapsulate it from saltwater damage.
>
> > Of course environment makes a difference. A while back, at considerable
> > expense I installed a trap beam antenna made in Minnesota, I believe.
> > It soon became obvious that the people who made it were a long way from
> salt
> > water.
> > Given only a moderate bit of bad wx the traps had failed due to salt
> > corrosion within three weeks.
>
> This is a real problem (the station at EA8BH almost has to be
completely
> rebuilt every year for the same problem) but I'll bet you a nickel that
this
> isn't the first antenna that you've installed that suffered from this fate
so
> you basically put it up and crossed your fingers.
>
> Okay, so what can you do to prevent this from happening? Maybe not use
an
> antenna with traps. Maybe coating the antenna with some sort of commercial
> coating. What do the commercial boys do in your area? I'd talk to them to
> find out - I'm sure thev've got some tricks they would be happy to share.
Ask
> on TowerTalk - there are people who have 'been there - done that' and
would
> probably save you some grief.
>
> OTOH since your antenna came from Minnesota, it was probably very good
at
> getting through snow and ice-storms - hi.
>
> > Advice from a local dealer and RSGB is that no product gives more
problems
> > and failures than rotators.
>
> I totally agree. IMO 6-7 years service is about all you can expect.
But a
> failed rotator isn't normally catastrophic and can generally be replaced
> easily.
>
> > Have also heard of late that the famous ARRL Antenna Book "A frame
mast" is
> > a joke. Out here the numerous A frames standing after 70 years or so
are at
> > a loss to see the joke.
>
> I'm not saying that it's not an okay structure for your environs and
> application. Any wooden A frame here in soggy Washington State has a MUCH
> more limited life than in your situation. Again, "GO with what you've
got'.
>
> > Force 12 advise that like any other mechanical system a beam antenna
needs
> > maintenance, like pulling the joints apart and cleaning and regooing,
> > replacing or cleaning connectors etc.
>
> Probably couldn't hurt but I don't know of too many people who
actually
> do that. Annual element polishing is another matter (that's a joke, son!).
>
> Everyone has some unique circumstances that need to be addressed if
> you're going to meet your 10-year goal. The guys in Texas get lots of wind
so
> extra care needs to be taken with antennas. Your situation with saltwater
> corrosion means you need to take that into consideration for YOUR
> installation. High altitude, extreme heat or cold, etc. are other unique
> parameters that need to be addressed. But if you take them one-at-a-time
with
> some proper prior planning and execution, your installation just might
meet
> our ten-year goal.
> >
> > Just now I heard a rumbling sound.
> > Not an earthquake.
> > Just The Old Man (W1AW) turning in his grave, brandishing his
Rettysnitch.
> >
> He must be a TowerTalkian too!
>
> Cheers, Steve K7LXC
> Tower Tech
> Champion Radio Products
>
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