[TowerTalk] Ten-Year Goal

[K7LXC@aol.com]

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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