What is a HEX-BEAM?
A compact, lightweight, hexagonal shaped, directional beam.
Everyone knows a bigger cup holds more water. How can smaller possibly be better?
Designs with linear elements are based on the phasing and coupling of widely spaced, diffused fields along a boom or other structure. The H-B is based on the phasing and coupling of closely spaced, intense, flattened fields.
How could the H-B be a directional beam when it doesn't even have a boom?
Its "spacing" comes from the "W" shape of its elements.
For each "slice" of the field in the driven element, there is a mirror image "slice" of field in the reflector.
ASSEMBLY AND INSTALLATION
How high does a H-B have to be for it to perform well?
The HEX-BEAM works well at relatively low height. A minimum of 1/2 wavelength is recommended. For most communication 5/8 wavelength is preferred instead of the usual 1 wavelength. 40ft. works very well for 20M or multi-band arrays which include 20M.
Is the HEX-BEAM difficult to assemble?
The portable HEX-PAC array takes about 15 min. for someone familiar with the antenna. The first time user should expect to spend an hour or so. The 5-band HX-5Bi requires approximately 2-4 hours although some H-B users assemble the HX-5Bi in an hour or less.
What tools do I need for assembly?
For the HXL series and HEX-PAC portable array: 5/16 wrench, 7/16 open end wrench, #1 Phillips screwdriver
For the HXi arrays: 7/16 open end wrench, 5/16 wrench, #1 Phillips screwdriver, 3/16 Allen wrench (two 1/2" wrenches and a 5/16 drill are needed for your mast thru-bolt)
What adjustment and/or tuning is necessary to prepare the H-B for operation?
None required
Certainly element length, matching network, or something must be "tuned?"
The H-B is supplied pretuned for normal operation in its desired band(s). (If the array is used in unusual or abnormal environments, such as, very near the ground, another antenna, or a metal roof, its V.S.W.R. may be high and overall performance may be compromised -- this isn't considered "normal" operation).
What about matching network adjustments?
The H-B has no matching network to adjust. By design, the H-B's V.S.W.R. is 2.0:1.0 or less for operating bandwidth(s). This meets the requirements of most equipment in use today.
Should I use a balun?
Simply running the feedline vertical to element plane for approximately 1/4 wavelength has worked very well. A balun with "pig tails" shouldn't be used as it can dramatically affect antenna tuning. A coiled coax choke balun may be desired in certain installations. Almost every installation can benefit from the addition of toroids near the antenna, providing the permeability isn't too high for 10M. Five or six type 77 toroids installed below the antenna hub/baseplate make an excellent RF shunt. (Amidon 800-898-1883).
Is it really true that just a TV type rotor will turn the H-B?
Yes. The portable array weighs 7-1/2 lbs on 20M (20M HXL is similar). For the 20 lb. 5-band array (HX-5Bi), the heavier duty TV rotors are recommended. In extreme wind and ice locations a light duty ham type rotor should be used.
Do I need separate feedlines or a remote antenna switch for the multi-band H-B's?
No. H-B's require only a single feedline.
Can H-B's be stacked? See our Home Page.
Definitely. The benefits of a stack of H-Bs become most apparent during marginal conditions or when communicating with stations on different paths. If "bang for the buck" is considered, a single H-B at 5/8 wavelength is hard to beat.
GENERAL QUESTIONS
Antenna gain is very important to me, but I've heard there are other beneficial characteristics of the H-B. What are these?
We have received numerous reports that the H-B is less affected by QSB and audio remains more "intact." Also a pronounced rejection of "man-made" noise is often mentioned -- "I'm hearing stations I never heard before, etc." In "noisy" environments, the noise floor is often lowered by 2-3 S-units - sometimes 4-6 S-units.
I live in a "sensitive" neighborhood and don't want to put up a tower. Will the H-B work for me?
The light-weight HEX-BEAMs and portable mast set on a small rotor at its base (or manually rotated) works very well for this, and many other, applications where high performance in a small size is desired. Painting the completed installation to blend with surroundings also lessens visual impact.
Can I take a H-B with me when I travel?
The HEX-PAC array is designed for that purpose (it also works well as a mono-bander on 6-20M at your home QTH). Those using the H-B on DX-peditions find that just the cost of shipping a conventional array can often exceed the total cost of an entire H-B installation. Also, the H-B doesn't have to be shipped separately prior to your departure. Take it and a sectional or collapsing mast along with you as part of your luggage.
Do H-B's hold up to weather?
Yes, very well. The H-B configuration avoids the asymmetric loading problems associated with most beams. H-Bs have survived the ice and wind of the Northeast U.S.A and monsoon winds of the Pacific. At Bouvet Island winds in excess of 140 mph were recorded. The HB survived and remained functional for the entire operation though it was blown down numerous times.
What about cost?
When overall system costs are considered, the total savings when using H-Bs can be very substantial, often thousands of dollars. For example, a mono-band H-B and its rotor often cost less than just the rotor required for a conventional antenna with similar performance. Site work costs are virtually eliminated. H-B users are very pleased at the high level of performance they have received for such a modest investment. Some who have previously used large, complicated, and expensive systems feel the H-B is a bargain when bang/$ is considered. Also, we receive many compliments regarding the quality of the finished H-B. First time users are surprised to find how simply and quickly they get on the air -- "the hard work is already done."
FOR MORE INFORMATION: "Ask the ham who has one" or call 888 599-BEAM.
Traffie Technology, 421 Jones Hill Road, Ashby, MA 01431, Phone: 978-386-7900, Fax: 978-386-7905
Copyright ©2008, Traffie Technology. All rights reserved.
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