Patrick
I second Tim's advice.
I built my own low band vertical using 23 ft of tower and stinger above it.
But it is not the same as HyTower. HyTower also has an insulator at the top
of the tower to let the stinger be electrically connected to the base plate.
Apparently, according to W8WWV, the tower acts somewhat like a cage loading
if I understand correctly.
In my case, I eliminated the top insulator so that the stinger is
electrically and mechanically attached to the top of the tower. It is base
loaded for 160. It has a 60 meter trap at approx. 43 ft up. It is self
resonant on 80 and I have a remotely switched network at the base to make it
a 1/2 wave on 40. It works very well.
What I did for insulation is to buy 4 each HyTower insulators and I had a
special base plate made by a local metal fab shop. I have this whole
arrangement designed to be a tilt over antenna using a boat trailer winch
and a 20 ft "gin" pole that I raise first to support the antenna similar to
a falling derrick arrangement except that my derrick stays stationary with a
back stay to an anchor in the ground.. I can raise and lower the entire
assembly alone. I have engineering drawings which show most of it and photos
that show the rest. I still use Dacron guys at the 24 ft. point since we do
get some summer winds here that really rock the joint. The aluminum stinger
starts out at the tower as triple wall and then double wall and then single
wall as you get to the 60 meter trap. Above that I have a piece of aluminum
tubing with a CB whip above it to minimize the wind loading at the top.
Best Regards
Dan Schaaf
=================================
K3ZXL www.k3zxl.com
60 Meters www.60metersonline.net
=================================
NOBSKA www.nobska.net
Cape Cod Instruments www.gnm-inc.com
Tel: 941-766-0706
Fax: 941-766-0707
=================================
-----Original Message-----
From: Tim Duffy
Sent: Thursday, December 26, 2013 3:17 PM
To: 'Patrick Greenlee' ; towertalk@contesting.com
Subject: Re: [TowerTalk] Insulating towers
Hello Patrick:
I would not suggest you do either of these choices. The Rohn 25 tower is
heavy and the base insulator has to be able to support the tower and the
aluminum stinger down force and wind loads. I suggest you consult with Rohn
and follow their advice 100%.
The Hy-Tower insulators are made to be used with specific tower which is
much different than Rohn 25. Please do not try this.
You have to be very careful with tower installations as you are risking your
life and those working around you.
I would suggest you consult with a local mechanical professional engineer
before proceeding with any of your tower plans.
73,
Tim K3LR
-----Original Message-----
From: TowerTalk [mailto:towertalk-bounces@contesting.com] On Behalf Of
Patrick Greenlee
Sent: Thursday, December 26, 2013 2:39 PM
To: towertalk@contesting.com
Subject: [TowerTalk] Insulating towers
Any thoughts on insulating a tower? I have some Rohn 25 that I want to use
to make a home brew version of a Hy-Gain Hy-Tower multi-band vertical. I am
considering two approaches:
1. Buy a plastic cutting board to cut up for material to home brew
insulators to be electrically between the tilt base and the tower proper. (I
have a friend with MS Mech Eng and 35 years hands on experience who will, if
asked, consult on this or help me design it.)
2. Pay the $ and buy 3 insulators from Hy-Gain as replacement parts for a
HY-Gain Hy-Tower antenna.
Any thoughts on item 1 or other ideas to git 'er done.
Patrick NJ5G
-----Original Message-----
From: Jim Lux
Sent: Thursday, December 26, 2013 12:58 PM
To: towertalk@contesting.com
Subject: Re: [TowerTalk] Raising Towers
On 12/26/13 10:41 AM, Hector Garcia,XE2K wrote:
Some very interesting ideas, very ingenious and a lot to avoid
I got scare with his double braid rope as lanyard @200ft tower
Well, if you're raising it in your (big) backyard, and you're aware of
the risks, then you can use dental floss if you think it will work.
not FAA lights on 200ft towers?
That would be a problem.. Maybe his "200 foot" tower is actually 199
ft, 6", and exempt.
those bungee cords as insulators or for tension ?
I'm thinking some sort of shock absorption.
the anchor in the wash
no insulators in the guy wires.
if the guy doesn't happen to be "the wrong length", then there's no
particular reason for insulators (unless you're feeding the tower as the
radiator)
some good things to use and some ones to avoid from my point of view
be safe
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