I built 2 antennas out of aluminum wire bought at farmers co op, the
antennas were a 2 element full wave for 80 and 2 element for 40 meters.
The wire was about 1/16 inch and I used a real soft spring on each
corner, also bought at the co op. They both worked well for the 5
years
they were up until I had to cut the trees due to a oak virus or
something that killed the trees. I used butt splices to connect the
copper coax
to the aluminum and then silicone to seal them.
KO4O
Roger
-----Original Message-----
From: tentec-request <tentec-request@contesting.com>
To: tentec <tentec@contesting.com>
Sent: Fri, Jan 2, 2015 11:03 am
Subject: TenTec Digest, Vol 145, Issue 3
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Today's Topics:
1. Re: BUNGEE CORDS (Jim Brown)
2. Tree supported antennas (Ken Brown)
3. Re: QST from GERMANY (G Reichow)
4. Re: QST from GERMANY (Tony Lelieveld)
----------------------------------------------------------------------
Message: 1
Date: Thu, 01 Jan 2015 10:18:09 -0800
From: Jim Brown <k9yc@audiosystemsgroup.com>
To: tentec@contesting.com
Subject: Re: [TenTec] BUNGEE CORDS
Message-ID: <54A58F61.5080607@audiosystemsgroup.com>
Content-Type: text/plain; charset=windows-1252; format=flowed
On Thu,1/1/2015 4:41 AM, Rick - DJ0IP / NJ0IP wrote:
Keeping in mind that height is might, it is a lot easier for one OM
alone to
erect an antenna high in the air when using lightweight components
(e.g.
fiberglass telescoping pole, non-porcelain insulators, thinner
Copperweld
wire, and thinner Kevlar or Dyneema rope), than with traditional
heavy metal
poles and heavy wire and insulators.
Danger, Will Robinson! High antennas will end up on the ground if one
of their components is not mechanically robust. UV can quickly degrade
some of those lightweight components, like the bungees mentioned.
Several years ago, my good neighbor, an aero/mechanical engineer
working
in the space program, advised me that rope made from Vectran, a new
space age material, was the ideal support rope for antennas. We bought
a
500 ft spool. it was expensive, $300. I used a length of it to support
one end of my 160M Tee vertical. That was in early 2012. Last week, I
was re-rigging that antenna because the big Madrone that held up one
end
had died, and had to be cut down. I had intended to reuse the Vectran,
but the tree guys used new rope instead. That turned out to be a good
thing -- upon inspection, the Vectran was badly degraded by UV, the
antenna would likely have been on the ground in another year, and I
would have been paying a climber to put new rope through that pulley.
High wire antennas are heavy, mostly because of the long attached
feedline. Lightweight components ARE a good thing when they reduce
antenna weight. i like the new lightweight egg insulators, for example
-- even if they do degrade with UV, the antenna is not going to end up
on the ground. Some hams use small coax on high dipoles to reduce
weight, but that small coax adds a lot of loss, so I use RG8 or RG11.
If you don't want a lot of sag (and we don't, because the loss of
height
subtracts dBs from our signal), you need a lot of tension. Again, more
stress on components, like the center insulator.
"Thin copperweld?" AARGH -- I HATE copperweld. It's nasty to work
with,
and its brittle. I've never used it. That same neighbor built an 80M
dipole with copperweld and hung it between two trees at about 90 ft.
Two
days later it was on the ground -- the copperweld broke. He and I have
since standardized on hard drawn copper, which we buy as a 500 ft spool
of #8 bare copper from the big box store and stretch to make it hard
drawn. The process is pretty basic -- we cut it into suitable lengths,
tie one end to a fixed support (like a telephone pole or big tree), the
other end to the trailer hitch of his pickup, and pull very slowly
until
it breaks. I first did this about ten years ago, and we've done this
several times since. We typically get about 20-25% stretch, so that 500
ft becomes more like 600 ft of #9 copper.
If you don't want to go to that trouble, #12 or #10 THHN (insulated
house wire) from the local big box store works very well. Yes, copper
stretches under tension, and I've had to lower and circumcise my high
dipoles every few years to keep them resonant where I want them. That's
a major reason I've gone to hard drawn copper.
I like copper split bolt connectors to secure mechanical and electrical
connections. Solder tends to make a joint brittle, and more likely to
fail mechanically if subject to movement, and high dipoles DO move. :)
To me, the place for those lightweight components is portable
operation,
like Field Day.
73, Jim K9YC
------------------------------
Message: 2
Date: Thu, 01 Jan 2015 08:31:19 -1000
From: Ken Brown <ken.d.brown@hawaiiantel.net>
To: tentec@contesting.com
Subject: [TenTec] Tree supported antennas
Message-ID: <54A59277.5080906@hawaiiantel.net>
Content-Type: text/plain; charset=windows-1252; format=flowed
I use tree supported wire antennas, almost exclusively for the 14 years
I have lived at the present QTH. Here are a few hints worth considering:
Getting someone to climb a tree to get the line over the right branch
may be superior to using a sling shot or cross bow, or cast with a
fishing rod, because you can get the line exactly where you want it
that
way. If you can get it right by launching it up there somehow, then
good
for you. I'm using stainless steel eye bolts screwed into my trees. You
cannot install those with a crossbow. Palm tree "branches" don't last
long enough. A line over a stout branch will work fine for many kinds
of
trees.
Whichever way you get the line up there, do not use that line directly
to hoist the antenna. Use that line to hold up the block (pulley)
through which the antenna support line runs. This makes adjustments,
reconfiguration and repairs much easier. In fact it may be the
difference between repairs being possible, and having to start all
over.
It also reduces or eliminates rubbing of the line on the tree. A good
thing to reduce since that can damage the tree and the line.
Sadly, the junk at the two large hardware chains available to most of
us is likely not of the same quality as that used in the aircraft
industry.
Or the marine industry. DO NOT use hardware store pulleys. Even the
best
ones are not very good. Use small sailboat pulleys. If there is a
boating supply store around, check out what they have. Otherwise order
something on line. I have purchased mine from Westmarine. There may be
other boating supply stores on line, that is the one I know. I'm not
intending to promote them.
Use line that is the appropriate size for the job and pulleys the
appropriate size for the line. Even the best pulley can jam if the line
you run through is too big or too small.
The line that runs through the pulley should be a continuous loop so
that if you accidentally let go of it it cannot un-thread from the
pulley. You could put weights at each end of the line, which are too
big
to go through the pulley as an alternate method to prevent letting the
line fall out of the pulley. I find the loop method to work fine.
I have not found a need for bungees or weights on my lines. I just tie
them so that the antenna wire has a reasonable tension, but not too
much. If the trees at opposite ends are moving in the wind, and are not
in exact sync, it is not a problem. I haven't had an antenna break due
to that cause yet. This is no doubt highly dependent on the variety of
trees you are using. I have tall skinny palm trees. If you have a need
for a weight or a bungee, have it down near the ground where you can
tend to it.
When the antenna wire does break, or has something hanging from it that
you want to remove, you will be really glad you used a line through a
pulley. Mine usually collect palm fronds. (Probably because I am using
palm trees) I am amazed at how seldom the palm fronds break my wire.
They usually just hang there. I am using something like 28 AWG enameled
wire. I could use heavier wire, and require more tension to hold it up
as nicely. The small stuff works great for me.
Have fun, be safe. If you plan ahead it will last longer and you'll
have
less frustration.
DE N6KB
------------------------------
Message: 3
Date: Thu, 1 Jan 2015 18:52:51 -0600
From: G Reichow <wa0yle12@gmail.com>
To: Discussion of Ten-Tec Equipment <tentec@contesting.com>
Subject: Re: [TenTec] QST from GERMANY
Message-ID:
<CAMvEOmCtTqAMvJwjn31S4603qsBvjkFfTgMOVygQK7k9aZ5J6A@mail.gmail.com>
Content-Type: text/plain; charset=UTF-8
Thank you Rick and a very happy and healthy 2015 to you and your family.
Gary - KN0V
On 12/31/14, Rick - DJ0IP / NJ0IP <Rick@dj0ip.de> wrote:
Happy New Year to all TEN-TEC fans.
Health, happiness and peace to all . . . from Germany; January 1st,
2015.
73 - Rick, DJ0IP
(Nr. Frankfurt am Main)
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------------------------------
Message: 4
Date: Thu, 1 Jan 2015 22:50:14 -0500
From: "Tony Lelieveld" <va3dwi@gmail.com>
To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
Subject: Re: [TenTec] QST from GERMANY
Message-ID: <EEC8619E697340C7A9FE77C0222899F8@OwnerPC>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=original
Thank you Rick. Happy New Year to you and yours and a very Healthy
2015.
This goes for all on this list too.
73, Tony VE3DWI.
----- Original Message -----
From: "Rick - DJ0IP / NJ0IP" <Rick@DJ0IP.de>
Happy New Year to all TEN-TEC fans.
Health, happiness and peace to all . . . from Germany; January 1st,
2015.
73 - Rick, DJ0IP
(Nr. Frankfurt am Main)
------------------------------
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