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SUBJECT: VHF/UHF stealth beam antennas

Let's look at a couple of points here first. From my last posting, the
relative sizes of the different antennas show that hiding a 6m antenna
can be a lot more difficult than hiding a 70cm antenna.

6m beams can be large and hard to explain as a TV antenna. Many PUDs/Condos/
Apartments do not permit TV antennas at all. 

For places that allow TV antennas, I have some tricks that you can do inorder
to play on the bands. These tricks will be discussed later.

Beams are a necessity in some locations. The gain achieved on a beam can mean
the difference between getting in the repeater, digi-node, making a simplex
or SSB contact. The easiest installation would be in an attic, but most
hams can figure that out.

Unless you only require a fixed position, a beam will require a rotor to 
fully utilize the quality the a beam can provide. Beams are generally single
band antennas when used above 10m. I would recommend a log periodic for use
on the VHF/UHF frequencies to provide the ham with multi-band operations.

There are some problem that must be addressed when working with beams.
First, different polarities are required for different operations. FM and
packet use vertical while SSB and CW require horizontal. Space communications
requires a combination of the two or circular polarization. 

Second, hiding a beam and it's associated support equipment can be a pain in
the butt when the QTH says no antennas. Anything that must rotate is going
to draw attention. Fixed beams can be hidden. Rotating beams are going to
require a bit more. 

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Remember that size plays a big point when stealth is employed. I'll look
at the 2m beam for the examples here and the relation can be applied to
the other bands.

       Horizontal operation: This is the easiest beam to hide. Be sure you
know all the rules of your association or apartment before attempting to
install a beam. The beam, because of it's polarity, is flat. It can be
passed off as a TV antenna for a specific channel. Most people wouldn't
know the difference. The outside installation can be accomplished with
the basic TV installation. By adding a second rotor, such as an elevation 
rotor, both vertical and horizontal polarization can be accomplished.
I recommend the vertical operation for night time use only. It eliminates
the question; "Why is your TV antenna like that?"

       Stealth operation:
You may not be able to put up a TV antenna and must totally hide the beam.
Attics are an easy hiding place. Upper rooms are good too. Telescoping 
elements for portable operation work well. I would like to relate some
unique installations to overcome the no antenna rules.

       This Amateur had a bad time trying to locate any antenna at
his dwelling. He lives in an apartment complex. His apartment is on the
inside, second floor, of a four story apartment building that is shaped
into a large rectangle.

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               |                  X                    |
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The X indicates where the apartment is located. There is an apartment on
the outside of his. Like I mentioned, he was on the second of four floors.
No antennas are allowed outside the apartment. He had a couple of options.
One, he could move, but funds weren't there. Two, he could use his noodle
to figure out how to beat the system.

This ham enjoys UHF operations from 440-450. He also works 2m packet from 
time to time. Most people would stick to stamp collecting at this point.
 
There are additional problems facing this ham. Windows on the upper floors
would expose him to masts, cables and devices to raise or lower his antennas.
On top of that, the roof of the building is steeply sloped. Mounting anything
up there, let alone getting up there was a problem. 

    A steeply sloped roof means a large attic. The ham in question is an 
    electrician, by trade, and was employed by the owners of the building to
    rewire part of the top floor hallway lighting. The job was to take place 
    in a weeks time. It was all the time he required to assemble a set of
    beams, with rotor control. The coax and control cables were to be run
    down next to the electrical conduit into his apartment. He purchased
    two beams, a 2m and a 70cm, to facilitate his requirements. A TV rotor
    was employed to rotate the set and the antennas were mounted side by side.
    The 2m beam was a simple four element model and the 70cm model was an
    eleven element model. In addition to the beams, he also installed two
    omni directional antennas. The total set was mounted to a short mast and
    base. It took a mere two hours to assemble the system and one hour extra
    to run the cables. He was in business. He mounted the system over a 
    stairwell and service closet. He also mounted the base over a foam pad to
    inhibit the rotor noise. This ham is in the Central Florida area. He is
    a Technician Class operator and has been operating this way for over
    three years now.


This is an example of fixed beam installation:

    This ham lives in a condo complex south of a large city. No antennas are
    allowed. His unit is on the second floor of a two floor unit. This ham
    enjoys 2m SSB. Since he owns the condo, this ham was able to modify the
    roof of his screened in porch to accommodate a unique masting system that
    can be raised and lowered from inside the porch. He employed a three 
    section mast made from aluminum tubing. The eleven element 2m beam was
    fitted with rubber feet under all the elements and the boom. After that,
    the beam was painted a dark flat grey to blend in with the night sky, even
    under full moon conditions. The upper mast sections were also painted 
    in the same manner. During the daylight hours, the beam was lowered 
    against the aluminum roof and was well out of sight from the neighbors.
    At night, the beam was raised enough to clear the top of his roof.

    Raising the antenna mast took a bit of planning. The roof of the porch
    was 7'6" above the deck. A pulley system, similar to a patio umbrella
    device was employed to raise the mast sections. The mast was placed in the
    center of the roof and a table supported the base. A plastic vine type 
    plant was used to disguise the bottom section along with a planter to
    finish off the stealth set-up. The coax was run to the planter and then
    connected to another coax when it was to be used. The ham in question
    has been operating this way for a few years with good success. 

The installation of a beam requires thought and planning. I can not give
plans for every installation. This is mostly dependent on the amateur. But
these ideas may give you some ideas on how to beat the rules and enjoy
your hobby.

73, WS