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write your own review of the Andrew Heliax.
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WD6DBM
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Rating: 5/5
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Dec 5, 2005 01:04
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Must have for VHF weak signal
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Time owned: more than 12 months
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I replaced a 50' run of 9913 to my 2m EME antenna with an 80' piece of Andrews 7/8" Heliax. I measured the difference with a Bird 43 at the antenna and saved .72db! That is an amazing savings for such a short run. Now the total loss including jumpers and myriad connectors is a mere .62 db. You can get good deals at hamfests of cable chunks with connectors already installed. Anyone who works EME will tell you every .1 db counts, and Heliax is the way to save them. This used piece has now been on my roof for 13 years.
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KB9WIS
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Rating: 5/5
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Aug 1, 2005 12:19
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Commercial Quality for Amateurs
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Time owned: 6 to 12 months
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Working on the airport's communications equipment, (I'm a FAA communications tech) you quickly find out why Andrews Heliax is the government's FAA 50 ohm cable standard. Lower loss, higher wattage handling, increased durability, and the ease of putting on the connectors on even 7/8" thick cable, you can't go wrong. We often measure/test the loss of the Heliax versus the RG 214/213 at VHF and UHF frequencies, and the difference can often make a full quieting signal from an airplane that is lost in the noise, become fully readible.
I was so impressed, I decided to upgrade my Amateur radio cabling to Heliax. No more RG 8/u and/or RG 213 for me!
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W6LBV
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Rating: 5/5
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Jul 31, 2005 20:22
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Go with the Pros
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Time owned: more than 12 months
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Andrew Heliax transmission lines and connectors should be the "secret weapon" of the Amateur Service. The following are results and recommendations based on both Amateur and commercial experience with Andrew. In summary: if there is any way you can obtain these transmission lines and connectors for your ARS station.....DO IT! These are superior products that are the "standard" of the commercial radio industry.
There are two separate Andrew product lines of interest to Amateurs, Heliax (semi-rigid hard line) and Superflex (flexible hard line) and some different products within each line. Heliax uses the nomenclature LDF"n", and Superflex the nomenclature FSJ"n", where "n" is an integer. Larger values of "n" indicate increasing cable diameter, lower line losses, greater power handling capability, and greater expense. The connectors are not interchangeable between equal diameter lines in the two series. My commercial practice (probably grounded more in "religion" rather than fact) was not to use Superflex for any outdoor applications; all main lines and jumpers outdoors were always Heliax.
For home station use, LDF4 (½ inch Heliax) is probably the best compromise for cost, availability, ease of handling, and low signal loss. I used it for the main run to my HF Yagi with a short RG-213/U jumper at the antenna, and the performance is outstanding. Even at 29 MHz, ninety-five of every hundred watts from the transmitter flow into the driven element. I also use it for all home VHF/UHF antennas > 100 MHz. LDF5 (7/8 inch Heliax) is probably the largest size one would want to attempt at home; it will handle "full legal power" on all ARS frequencies. LDF6 (1 1/4 inch) and LDF7, (1 5/8 inch) become "heroic" for hams, in terms both of cost and of ability to handle during installation. Still larger diameter Heliax is commercially available, but is used generally by multi-kilowatt broadcasters. For all cables, a "rule of thumb:" the minimum allowable bending radius is ten times the cable diameter (but check exact specifications on the Andrew Web page).
Another "secret weapon:" FSJ1, 1/4 inch Superflex. About the same diameter as RG-58/U, it has the low losses of good RG-8/U, and 1 kW average power rating to 150 MHz. It's excellent for indoor jumpers (used commercially for this purpose even into the microwave bands) and for mobile installations. It installs well directly into PL-259 connectors (Teflon dielectric PL-259s are preferred) using the screw-in RG-58 cable size reducer. For Type N systems, the exact Andrew connector should be used.
New Andrew lines and connectors, while expensive, are the best bet, and they can be amortized over a twenty-year (or longer) working lifetime. Don't overlook the possibility of "salvaging" Andrew parts from commercial sites being taken down. Most commercial operators will not re-use existing lines, connectors, and cable mounting clamps that have been removed from a site. Visually inspect and clean them and measure salvaged line/connector assemblies for actual loss at your operating frequency. Even if the line is damaged, with some care the connectors can be cleaned up and re-used, a process which is not economical for commercial operators.
"No one was ever fired for specifying Andrew transmission line systems."
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K3GM
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Rating: 5/5
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Feb 28, 2005 10:35
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...the best
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Time owned: more than 12 months
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I've been using Andrew FSJ4-50 on all of my feedlines for 50MHz and up, and have become acclimated to working with it. If you're hesitant to use it because attaching connectors sounds like a big deal, don't be. Armed only with a Zona saw, a razor blade, and a solder iron, I'm able to install an Andrew connector in under 15 minutes. Ater you do a couple you'll find it's extremely easy.
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KI6LO
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Rating: 5/5
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Sep 15, 2003 18:34
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Good stuff but a bear to work with
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Time owned: more than 12 months
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If you watch Ebay or like places, you can find NEW heliax for a song. I got 200' of Andrew's FSJ4-50 1/2" heliax for $1 a foot. And this wasn't a spool end reject either. It was a packaged from the factory 200' roll.
It is great stuff with almost no loss at HF, very low loss at VHF and just starting to creep into noticable loss at 440Mhz.
It's limitations are in the installation. I had never worked with heliax and it was like trying to wrestle an alligator to route the cable where it needed to go. The connectors require a little patience also but once on, the are very secure. Recommend short jumpers of RG213 or such at the radio end and especially at the rotor and antenna end.
The Andrews connectors can be found cheap on Ebay and like. Any additional costs above regular coax (RG213, etc) is well worth the savings in power loss to the antenna.
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K9KJM
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Rating: 5/5
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Mar 27, 2002 16:10
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SIMPLY THE BEST
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Time owned: more than 12 months
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This type of cable may be beyond the means of lots of hams to purchase new, But shorter lengths of 100-200 or so feet are available surplus from swapfests and commercial tower companies, etc. Connectors are also available used for fair prices, and at discount from some suppliers. For serious VHF/UHF use, and High power H.F. use, Get the BEST! I have even "made" my own connectors with copper pipe fittings and used "N" chassis connectors years back. While not pretty, They did work, And I had very low loss UHF feedline on a tight budget!
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KA2VTI
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Rating: 5/5
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Feb 18, 2002 10:15
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Overall electrical and mechanical performance is unparalleled
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Time owned: more than 12 months
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My experience with Andrew Heliax is both professional and amateur. Being involved with the cellular site construction industry I am intimately aware of the necessities of low loss and high reliability of feedline products.
The Andrew corporation is regarded as the premier manufacturer of coax in the world. Regarding our use of this product in the amateur frequencies disregarding the ill perceived high initial cost allows for extremely low loss of signal under extended feedline conditions and practicly unlimited life expectancies.
The losses heretofore considered normally acceptable at extended lengths (Over 100')with readily available coaxial feedlines such as RG-8X and RG-213 and the like with definitive life expectancies, are many times the loss associated with even 1/2" Andrew Heliax.
Looking at the losses of the popularly utilized, standard larger sizes such as 7/8" and 1-5/8 the losses are appreciably less as the size of the cable increases.
Although there are a great amount of hams out there able to recite and calculate loss formulas in their heads, I am alas not one of them.
Suffice it to say I am but an "avid amateur", however we all can appreciate coax with loss figures of a third each time the diameter is increased. (ie. 1/2" to 7/8" to 1-1/4" to 1-5/8")
Occasionaly I have laboriously calculated true feedline losses for HF, VHF and above and replaced in the calculations 1/2" or 7/8" Heliax for the more flexible RG-213 I had previously used and saw quite a difference. As is customary of late I should mention depending on the length of your feedline runs "your actual mileage may vary".
The range of conditions Heliax can be used under is wide. From laying it on your roof, directly burying it to running it under water, unless you damage the outer vinyl jacket it is truly impervious.
One condition where it can't be expected to last is continuous movement. The low losses and mechanical strengths are born from a continuous copper outer jacket under the vinyl protective cover. This copper jacket is a molded rib (not a spiral) to afford you the ability to make bends and arcs during installation but not continuously flexible as is needed between a stationary tower and rotatable antennae mast. A piece of low loss woven jacket coax is the best choice at that juncture.
There are not many applications where Heliax would not enhance station performance on any frequency as long as the flexibility issues are respected.
For more information see Andrew's website at... http://www.andrew.com/products/heliax/default.asp
Catalog 38 will make available more information than you could imagine.
For a brief and easily understandable overview in average "Ham" terms you can E mail me at ka2vti@arrl.net and I will forward you some basic specifications.
Oh, one more thing... If you run more than 5 or 10 thousand watts go with the 7/8" or larger and watch that SWR, other than that you can just have fun.
7 3 and Happy Hamming de ka2vti (Frank)
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