info@alpha-beta.ca
COMMUNICATION TOWERS
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Communication
Tower is a generic term that also includes Broadcasting
Towers, Microwave Towers and AM Towers. Communication Towers
are typically designed as antenna supporting structures,
whereas AM Towers act as the actual radiating element and
because of the relatively long wave length of the commercial
AM signals, a long radiating tower/mast is required. AM
towers have to be isolated from the ground. These towers
transmit very high electromagnetic radiation, sit on
insulators and also have their guy cables insulated from
direct contact with the ground. Even though AM Towers are
for the most part "active" or "hot" towers, they can also
act as supporting structures for conventional FM antennas if
special precautions are taken.
Antenna
arrays on Broadcasting Towers typically transmit high-power
FM signals in the tens of thousands of watts, mostly for
radio or television
broadcasting
purposes Microwave Towers are mostly used for transmitting
high-frequency microwave signals from tower to tower and
yet,
Microwave
Towers can also support broadcasting systems and
Broadcasting Towers can also support microwave and other
antennas.
In Canada,
the term Communication Tower is often used to describe a
lattice type of steel structure designed to support
antennas, but may also include
monopoles
and other construction types.
Communication
towers come in all sizes, made to support different types of
antennas at various heights, suitable to withstand different
environmental
conditions.
Most towers are made of hot-dipped galvanized steel, some
smaller towers or towers designed for special application
are made of aluminium or
other,
typically non-corrosive material.
In order to
be able to quote you the right type of tower for your
application (with or without installation), we need to have
a reasonably good understanding what your tower is to be
used for. Most established radio broadcasters,
Telecommunications companies or commercial entities
operating wireless networks have a clear understanding of
what kind of tower might be needed, but this is often not
the case for the first-time buyer. During the past years,
the demand for small to medium-size communication towers has
dramatically increased to facilitate high-speed wireless
Internet installations serving rural communities. Towers are
also still purchased by HAM Operators to support the
antennas for their amateur radio stations or by residents in
rural settings to pick up TV and FM signals. Specialty
towers may also be used for environmental measuring
equipment, anemometer for wind-speed measurements,
scientific research installations and many other
applications. We would appreciate it, if you could provide
us with the applicable answers to the questions below before
you contact us for pricing and other
information.
Free-standing
(self-supporting) towers for light applications might be
made of pre-galvanized + 16 gauge steel, diagonal
angle iron horizontals or diagonals, often come in 8 - 10 ft
sections where each section slip-fits into the next section.
These towers might reach a height of up to 100 ft, and are
typically not built to CSA approved procedures. Towers can
also be constructed from tubular steel for the tower legs
and solid rounds to be used as diagonals and horizontals.
Stronger towers might use solid steel rounds for their legs
and each all-weld constructed section could be up to 20 ft
in length. Tall, heavy-duty towers are often constructed
from hot-dipped galvanized steel where the tower legs are 20
ft in length and made of 60 degree angle iron with their
horizontals and diagonals constructed of 90 degree angle
iron. These towers are also called knock-down towers,
since they are shipped in pieces to be field assembled on
site.
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In
order to serve you better, we need answers to the
following
questions:
- Where will the tower be
located?
- What is the height of the proposed
tower?
- Does the tower need to comply with
CSA-S37-01 or other standards?
- Does the tower need painting in
international orange-white?
- Do you require tower
lights?
- When would you need the
tower?
- Is the site accessible to 2-wheel
drive vehicles?
- Is the site accessible to commercial
concrete mixer and heavy equipment?
- Any special access restrictions we
should be aware of?
- Would there be any restrictions
concerning construction hours at that site?
- Are you the owner of the property and
if not, who is?
- What type of tower are you looking
for (freestanding, guyed or
cantilever-mounted)?
- Is a recent geological survey
available?
- What is known about the soil
conditions in general?
- How far below grade is
bedrock?
- Are there hydro lines, phone lines or
other obstructions close by that might impede the
excavation for foundation or anchors or the erection of
the tower?
- Who would be responsible for the
removal of excavated material?
- Is hydro available on
site?
- Is a communication shelter required
and if yes, please specify.
- Do you need a wave guide bridge,
cable tray or messenger cable from near the base of the
tower to the communication shelter?
- Do you require anti-climb
shields?
- Is a safety rail or another type of
fall-arrest system required?
- Other
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Antennas
- What types of
antennas are used?
- What is the
elevation where these antennas are mounted?
- What is their
azimuth?
- What kind of
transmission lines will be used?
- Will the
transmission lines be fastened to the tower with
stainless steel hangars or is ty-wrapping
sufficient?
- Do you require
ice guards/shields to protect antenna(s) from falling
ice?
- Will you add
more antennas in the future?
We
Make Some Assumptions When We Quote
- That detailed
information on the soil conditions is available that can
be used for the design of foundation and/or
anchors;
- We charge
upward of $4,000.00 for a basic soil analysis and
geotechnical report if requested;
- Tower
foundations are site specific; Without a Geotechnical
assessment, our engineers will not be able to design the
right foundations or anchors and therefore, our quotation
would assume the following:
- That the soil
is non-acidic;
- Foundation and
anchors are in loose, undisturbed soil;
- Self-supporting
or freestanding towers up to 150 feet will have surface
forming only of about 5-1/2";
- That no water
or bedrock is encountered;
- That all work
is done before frost;
- Cable locating
is done by others;
- Excavated
material will be disposed off by others;
- All permits by
others;
- Invoice(s)
will be paid within 30 days of date of invoice. Financing
charges are 2.5%/month;
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This web page was updated last in April 2007. For comments/feedback on our Web pages, please contact Web Master.Thank you.