Where can I find an inexpensive, freestanding (or lightly guyed), antenna
tower? It doesn't have to support a lot of weight - a couple of small 2m
radio antennas and one or two scanner antennas. And it also doesn't have to
be very tall - thirty to forty feet would be just fine. I'm sure others
would be interested in this also.


Dwight Stewart (W5NET)

http://www.qsl.net/w5net/

"Dwight Stewart" wrote in message
.. .


Where can I find an inexpensive, freestanding (or lightly guyed),
antenna
tower? It doesn't have to support a lot of weight - a couple of small 2m
radio antennas and one or two scanner antennas. And it also doesn't have
to
be very tall - thirty to forty feet would be just fine. I'm sure others
would be interested in this also.


Dwight Stewart (W5NET)

http://www.qsl.net/w5net/

If they still make it, the Rohn HBX series would be the least expensive.
(Notice, I didn't say cheap). It comes in 8 foot sections that bolt
together. The top section is the skinniest, about 6 in on a side, and
sections get progressivly larger towards the bottom. It is light enough that
one person could lift a 32 foot tower. Good for 10 sq. ft. of antenna. Self
supporting, if you mount it on a concrete base.

Another low end tower is the USTower MA40. This is a tubular crank up tower
with a hinged bottom. You either need their raising fixture (expensive) and
a concrete base, or support it at about 8 feet against a building. It comes
with the building support bracket; this method only requires a few bags of
concrete. Also rated at 10 sq. ft. of antenna.. With this tower the rotor
can not be mounted inside the tower, and you can not use a thrust bearing.

If you live in a fringe TV area that recently got cable, you should be able
to get a TV tower for free if you take it down. The ones I see in South
Jersey seem to be 40 - 50 feet.

Tam/WB2TT

Radio Shack's telescoping masts work well and are cheap.

Do you need to climb it?

jw
wb9uai

In message , Dwight Stewart
writes


Where can I find an inexpensive, freestanding (or lightly guyed), antenna
tower? It doesn't have to support a lot of weight - a couple of small 2m
radio antennas and one or two scanner antennas. And it also doesn't have to
be very tall - thirty to forty feet would be just fine. I'm sure others
would be interested in this also.

I have a 25 ft pole made of plasticised paper, in 4 sections, with brass
inserts at each end. Ex-army. I paid 5 GBP (nearly a week's pay) for it
in 1953!

I used it guyed with light plastic line. It supported a 10 ele 2m beam
for several years.

Mike
--
M.J.Powell

"Dwight Stewart" wrote in message
.. .


Where can I find an inexpensive, freestanding (or lightly guyed),
antenna
tower? It doesn't have to support a lot of weight - a couple of small 2m
radio antennas and one or two scanner antennas. And it also doesn't have
to
be very tall - thirty to forty feet would be just fine. I'm sure others
would be interested in this also.


Dwight Stewart (W5NET)

http://www.qsl.net/w5net/


Go to your hardware store and buy a Aluminum ladder. Clamp it to the side
of the building and guy as necessary.

Just an idea.

Dan/W4NTI

"Dan/W4NTI" wrote:

Go to your hardware store and buy a Aluminum
ladder. Clamp it to the side of the building
and guy as necessary.


As described in a previous message, there isn't a lot of room for guy
wires. The area is about two and a half feet wide - just enough room for a
cement slab to support a small freestanding tower. After that, there just
isn't any room to run guy wires out very far. What there is (the building
and a nearby fence) isn't going to provide a strong support for guy wires.


Dwight Stewart (W5NET)

http://www.qsl.net/w5net/

"Brian Kelly" wrote:

A shallow concrete slab will not support any
tower unless the tower is well bracketed to
the house. There are only two choices: A large
block of concrete for the base or a slab with
a house bracket.


The word "slab" was probably a poor choice. I was mainly referring to the
width, not depth, of the concrete. The concrete will pretty much fill the
entire hole below the ground surface.


Use a mast made from steel pipe. I've used 'em
several times, works fine. Assume the bottom
section of the mast is made from a full length
of standard 2.5" Schedule 40 galvanized steel
pipe x 21 feet long. Top the base section with
a couple 10-12 foot lengths of smaller diameter
pipe and assemble the mast & antennas. Drive a
five foot length of 3" pipe into the ground,
clean it out, raise the mast to a vertical
position and drop it into the 3" pipe. (snip)


To make it freestanding, one would have to use some fairly thick steel
pipe (both wall thickness and pipe diameter), especially for longer lengths.
And pipe that heavy would almost require a crane to move it around. Because
of that, steel pipe might be fine for shorter masts (or guyed taller masts
using thinner pipe), but wouldn't really be feasible for a taller
freestanding structure (unless one owned a crane, but then the crane itself
could just be used to support the antennas).


Dwight Stewart (W5NET)

http://www.qsl.net/w5net/

"Crazy George" wrote in message ...
Brian:

You should mention to telescope the sections, rather than using threaded
reducing fittings, which are not strong enough for this kind of application.
Out of curiosity, how much overlap do you use?

I've done it both ways depending on a lot of variables. I noramally do
use threaded pipe reducers. As long as they're either steel or wrought
iron that is. The cheap hardware store cast grey iron reducers are
non-no's. I retap the reducers to get more thread engagement length.
It's been demonstrated that Schedule 40 pipe will fail in bending
before decent reducers fail. But in situations where the loads get
dicey and/or parts of the mast are tubing vs. pipe I use at least six
inch overlaps and have the joints welded.


--
Crazy George

w3rv

"Dwight Stewart" wrote in message
.. .
"Tarmo Tammaru" wrote:

If they still make it, the Rohn HBX series would
be the least expensive. (Notice, I didn't say
cheap). It comes in 8 foot... (snip)


Yep, that's the best I've found so far.

Dwight,

My first tower consisted of 3 sections of Rohn HBX. This gave me 24 feet. To
the top of this I added a 10 foot piece of 2 inch OD Al pipe. This was
fastened to the tower with angle iron and U bolts at the top plate and the
rotor shelf. Somebody gave it to me. It actually started life as a Hygain
vertical. The middle of the second section was fastened to the end of the
garage with TV house brackets. The ground mount consisted of three pieces of
pipe driven into the ground, with 1 bag of concrete to add some strength.

BTW, have you considered a roof tower? Even a garage roof would give you at
least 12 free feet.

Tam/WB2TT

Dwight Stewart wrote in message ...
"Brian Kelly" wrote:

A shallow concrete slab will not support any
tower unless the tower is well bracketed to
the house. There are only two choices: A large
block of concrete for the base or a slab with
a house bracket.


The word "slab" was probably a poor choice. I was mainly referring to the
width, not depth, of the concrete. The concrete will pretty much fill the
entire hole below the ground surface.

OK.

Use a mast made from steel pipe. I've used 'em
several times, works fine. Assume the bottom
section of the mast is made from a full length
of standard 2.5" Schedule 40 galvanized steel
pipe x 21 feet long. Top the base section with
a couple 10-12 foot lengths of smaller diameter
pipe and assemble the mast & antennas. Drive a
five foot length of 3" pipe into the ground,
clean it out, raise the mast to a vertical
position and drop it into the 3" pipe. (snip)


To make it freestanding, one would have to use some fairly thick steel
pipe (both wall thickness and pipe diameter), especially for longer lengths.

That's nonsense. If you want a properly-designed pipe mast you do it
by the numbers, not with amateur "eyeball structural engineering"
and/or broad-brush statements like "have to use some fairly thick
steel pipe . . ". You won't know a thing about any pipe sizes until
and unless you run the numbers. A 40 foot pipe mast analysis is as
simple as it gets in the field of applied mechanics, any sophomore
student in any engineering discipline including the EEs who brought
you your HT can handle the job. A pipe mast is just a classic
cantilever beam.

And pipe that heavy would almost require a crane to move it around. Because
of that, steel pipe might be fine for shorter masts (or guyed taller masts
using thinner pipe), but wouldn't really be feasible for a taller
freestanding structure (unless one owned a crane, but then the crane itself
could just be used to support the antennas).

You gather up five buddies. You hang a pulley near the house bracket.
Run a rope from the ground, thru the pulley then down to the midpoint
of the mast. There's your "crane". Three guys walk the mast up and two
pull on the rope and up she goes.

Dwight Stewart (W5NET)

http://www.qsl.net/w5net/

w3rv

w3rv