Antennas for the Tower...

During the past year, AB4D has been off the air while expanding the QTH.  Now that construction is complete and the dust has settled.  I am again focusing my attention to expanding my capabilities on the HF bands, and to build a satisfactory antenna system for my amateur radio station.

HF 40/75/80 meters:  The antenna selection for those particular bands was fairly easy.  I previously used a horizontal dipole strung between two fixed points, fed with 600 ohm ladder line. It worked well for those bands. However, this time I wanted the antenna center supported by my tower.  Therefore, I installed another wire dipole fed with 600 ohm ladder line, but in an inverted "V" configuration.  The feed point is at 70 feet with the ends situated at around 25 feet from the ground.  It's working well at this time, and I have received good signal reports from other stations.   Although, I do note that I now have a small bit of measurable RF at the operating position.  I will work on that antenna to reduce the amount of stray RF.

To further enhance my operating capabilities on 40 meters, I plan to install a M2 40M4LLDD 4 element 40 meter Yagi on the tower.  Comments and reviews about the 40M4LLDD have been favorable.  Although not the biggest gun out there.  It fits both within my budget and the specifications of my tower, along with the other antennas and hardware I plan to add.   
 
Multi-band HF Antenna 20-10 meters:  I found, trying to choose an antenna for HF multi-band operation can be a daunting task.  There are many choices available, ranging in price from several hundred dollars to well over $8,000 dollars.  They come in all types of designs; linear loaded, shortened elements;  trapped; mechanically adjusted; and log cell; all with claimed specifications that sometimes make it hard to perform an apples to apples comparison.  I performed considerable research, and read a lot of reviews about the many antennas available on the market from various manufacturers.  Basically, all multi-band antennas present some type of compromise or issues.  Finding out the compromises, and determining if you can live with them can help you make an educated decision.

My initial goal, if possible, was to cover the bands from 40 to 6 meters with one large directional antenna.  However, I found many antennas that would accomplish that feat, and have good specifications while being compatible with my tower, were antennas that had as I would say, "other issues".  The first antenna design I considered was the Steppir. A lot of hams who own Steppir antennas like them.  However, there have been some spotty reliability and mechanical strength issues. The Steppir antennas are complex, heavy, and seem to be one of the most expensive antennas on the market.  I priced out their newest beast, the Dream Beam 42.  With options, the antenna was priced at well over $8,000 dollars before delivery, and they did not recommend placing one on my HDX tower.  I also reviewed one of their more moderately priced antennas, a 4 element Yagi.  That antenna approaches $3000 in cost, but the gain specifications were not all that much better than conventional 5 band beams costing significantly less, usually within one db or less.  The one db difference of gain probably would go unnoticed by most operators.  IMO band conditions and propagation path play a more important role.  Based on the reviews I've read regarding reliability, and some opinions that question Steppir's performance claims,  I decided to stay away from the Steppir.  Mostly, because I just didn't believe the antenna design can survive long term (10-20 years) without major component failures.  There are way too many moving parts involved in the Steppir for my liking.

The second line of antennas I considered, was the Optibeam antennas.  Optibeam antennas have been getting very good reviews from the amateur community.  However, like the Steppir these antennas are somewhat expensive, and unlike the Steppir, they are not readily available to U.S. amateurs.  The Optibeam antennas are made in Germany, and that equals to very inflated shipping costs, plus Customs fees for any individual in the U.S. who wishes to import an Optibeam.  If there was a stocking dealer in the U.S., I certainly would give an Optibeam serious consideration, but I find it hard to part with nearly an extra $1000+ dollars in shipping and Customs fees to obtain that antenna.  For some it's worth it, for me it's not.  Array Solutions is the only U.S. dealer for Optibeam, but sadly they do not stock them.  I believe Optibeam is missing out on a significant number of sales by limiting themselves to only one manufacturing facility.  IMO, a smart business decision would be to partner with someone in the U.S. to start manufacturing their antenna designs here as well.

I've also considered antennas from Cushcraft, Mosley, M2, Force 12, Tennadyne, and Hy-Gain.  Cushcraft offers what I consider are value priced antennas with moderate performance, they are good entry level antennas.  However, they publish what I believe are questionable performance claims for some of their antenna line.  Based on past experience with Cushcraft, the quality is sometimes lacking.  The only exception is the Cushcraft X-7, that was designed by Danny Horvat E73M.  I found the X-7 performed well, and the boom and element components are exceptionally strong.  I wish many antenna manufacturers would supply such heavy duty boom brackets.  Nevertheless, even the X-7 arrived with a non-functional Balun that required replacement.  Cushcraft is now part of MFJ Enterprises, Inc.  Unfortunately, I suspect the quality has not improved with the change in ownership.  

Mosley is another brand of antenna I considered.  However, I read a significant number of complaints about Mosley antennas.  Many of the complaints are in regard to poor quality, and the relatively short life of their plastic components, traps, and trap forms.  Moreover, back in the late 90's, H. Ward Silver, N0AX and Steve Morris, K7LXC, performed extensive testing of multiple tri-band antenna, and published the results in a booklet titled, HF-TRIBANDER-PERFORMANCE-TEST-METHODS-RESULTS.  Based on what I've read from hams who purchased that report, their testing actually showed negative gain figures on some band segments for the Mosley antenna under test.

All of the above narrowed my available choices to antennas from M2, Force 12, Tennadyne, and Hygain.  All four of these companies seem to make quality products. I consistently read mostly favorable reviews about their products.  In regard to Force 12, they seem to make good products, but there were a few reviews that noted long term problems with their use of pop rivets for assembly.  I was considering the Force 12 5BA, but one commenter noted the longer elements can sometimes whip around in the wind, and touch other elements to the point that it caused his amplifier to "trip out".

Tennadyne offers log periodic antennas, that seem to be first rate. Their specifications and the reviews of their longer boom log periodic antenna are impressive.  If I had a second tower,  I would certainly consider one of their antennas as a second HF antenna.   However, I could not get the band coverage I am seeking using one of their antenna along with the other antennas and hardware I plan to install, without exceeding the specification of the HDX-572 tower 50 mph ratings.

Hy-gain and M2 are the two remaining manufacturers I considered.  I found that both had compatible antennas to fit all of my criteria, (cost to benefit ratio, band coverage, proven reputation of strength, acceptable specifications, and combination of weight and wind loading did not exceed the ratings of my tower).

Trying to find an antenna that covers 40 through 6 meters without sacrificing too much is problematic. Rather, I found it was better in my situation to run two monobanders and one 5 band antenna. As mentioned above, I am installing a M2 40M4LLDD 4 element 40 meter antenna.  The antenna has received favorable reviews, and M2 antenna are known to handle severe weather with ease. At least one well know installer of ham radio towers and antenna systems in the Northeast commented, that M2 antennas are the only ones that can survive the harsh New England winters. 

In relation to 6 meters, I also chose an M2 antenna, model 6M5XHP.  The antenna is a 5 element monobander that covers the bottom 300khz of the SSB portion of the band. The antenna offers reasonable gain and rejection.  I've previously used a similar antenna on that band.  When 6 meters is open, it is a fun band that requires very little power to make a lot of long distance contacts.


To cover the 10 through 20 meter bands, I chose a Hy-Gain TH-11DX 5 band antenna. Although the design may be considered dated by some, I was hard pressed to find any negative reviews about that particular antenna.  Rather, I found many favorable reviews and comments about the TH-11DX.

It is my understand that testing by N0AX and K7LXC revealed accurate published specifications from Hy-gain.

73

Photos of the feed line, static discharge unit, and inverted V antenna on the tower.