Right from the start, let’s be clear on something. I operate a lot of HF portable. I manage the W5-SOTA association, and I operate from many mountaintop locations. My LoTW profile has over 50 QTH locations entered in it. A look at my QRZ profile will give you the idea. After much experimentation, I had settled on the 88 foot doublet as my primary portable antenna. It was big, the 31 foot mast was over 5 pounds, and it took 15 to 20 minutes to set up, usually requiring a helper. But it did work well.
Frankly, I had seen the Alex-Loop antenna advertized a few times, and my thought was “Snake Oil”. How can a 3 foot diameter antenna possibly function well across 40m through 10m? I wasn’t willing to risk the price of the Alex Loop only to find out it was a gimmick.
In May of 2011 I was pondering a problem. I was going to Germany for 3 weeks and I needed a small antenna. I had lived in Germany for 8 years as a soldier, and I had many ham radio friends there. It was imperative that I get on the air with them for my visit. I had a Yaesu FT-817 portable radio, but I had no idea of how to get my 88 foot doublet and 31 foot Jackite Pole to pack small enough to carry on an overseas flight.
A week before the flight I still had no idea for the antenna. I was getting desperate. This was when an Alex-Loop Walk-Ham fell in to my lap.
With just a few days to go it arrived in the mail. The Alex-Loop Walk-Ham antenna came in a nice padded carry bag, and the total weight was just less than 3 pounds. The small size and weight would be easy to pack. In fact, it fit inside the backpack I used for my carry-on, and my entire portable station would fit in that back-pack.
After unpacking it, I read through the directions quickly, and set it up for a test. I stuck it up in a camera tripod on my patio. The antenna was about 4 feet off the ground. I only had time to make 4 QSOs on it before packing to leave. It was a very hot West Texas afternoon in early June. The first two QSOs were on 20m, and were at a range of about 1200 miles. The reports were promising. Not S-9+, but fully readable with 5-watts SSB from my FT-817.
I quickly tuned to 40m. Now, 40m on a hot West Texas summer afternoon isn’t the best band. The D-layer is active, and absorption is high. I wasn’t expecting much. But I heard two guys talking, so I broke in. They replied, and I had 2 nice contacts 400 miles away in Arizona. Again, this was with the FT-817 at 5-watts SSB. Surprising, to say the least. So I said a quick prayer, packed the Alex Loop with the rest of my gear, and got ready to fly to Germany.
That was 3 years ago. In that time, the Alex-Loop has become my #1 portable antenna. I have over 3000 portable QSOs on it now. The compact size has allowed me to operate portable from places where my doublet or even a buddi-pole with wire radials would have been impossible.
From the W5 region, using the FT-817 at 5-watts SSB or CW, I have worked into Alaska, Argentina, Australia, Brazil, Canada, Costa Rica, Cuba, Czech Republic, Eastern Kiribati (T32C), England, European Russia, Germany, Hawaii, Hungary, Italy, Japan, Luxembourg, Martinique, Mexico, New Zealand, Panama, Portugal, Puerto Rico, Slovenia, Spain, Virgin Islands, Venezuela and Wales.
From Central Europe, again using the FT-817 at 5-watts SSB or CW, I have worked Asiatic Russia, Austria, Belarus, Belgium, Bosnia-Herzegovina, Bulgaria, Canada, Canary Island, Czech republic, Denmark, England, Estonia, European Russia, Germany, Finland, France, Greece, Hungary, Ireland, Italy, Jersey, Netherlands, Northern Ireland, Poland, Portugal, Romania, Sardinia, Scotland, Serbia, Slovak Republic, Slovenia, Spain, Switzerland, Ukraine, United States and Wales. IT just works!
I have even been successful using it inside motel rooms, as long as it was near a large window.
About the antenna….
Alex Grimberg – PY1AHD is the builder of the Alex-Loop. His web site http://www.alexloop.com/ is full of information and ideas, and Alex is easy to talk to via E-mail. Alex is more than ready to help you build your own loop. He will answer questions and give suggestions to help anyone successfully roll their own.
The Alex Loop itself is made up of PVC pipe, coax, a variable capacitor, and assorted wire and other hardware. Someone with a good junk box could build one easily for a few $$$$. There is nothing magic or secret about it, and many have built their own.
Assembling the loop is as easy as slipping PVC pipe together, screwing in pl-259 connectors, and turning a knob. My portable station goes from back-pack to calling CQ in under five minutes. Packing it up to leave is just as quick. Tuning portable antennas (especially loaded verticals) can be a challenge, but the Alex-Loop will QSY from band to band in fifteen seconds or less. When properly tuned, I have never seen the SWR exceed 1.5:1 on any band. Best of all, there are no small pieces to lose.
Because the antenna has a high current when at resonance, it is imperative that the connections be clean and tight, or losses will kill the efficiency. This is why Alex uses gold-plated connectors, a nice touch. But you still must be certain the connections are clean and tight.
The Magnetic Loop antenna is a High-Q device. Getting it tuned properly to function is an absolute must. Trying to use it off-resonance will just end in frustration. Using an external tuner is just another exercise in frustration. Forget using a tuner, just get the loop tuned right and use it.
Being such a High-Q antenna has advantages and disadvantages.
The disadvantage is that the antenna tuning is critical, and you must constantly watch to see you stay in resonance. If you QSY, check it. It only takes a few seconds to re-tune. On the 10m, 12m, 15m and 17m bands, the loop is very easy to tune and a small QSY +/- a few KHz is not a problem. On 20m the tuning is a little more critical. On 30m the tuning is very tight, and on 40m I would call it “touchy”. Getting a good match on 40m takes a steady hand, and a QSY of 10 KHz will certainly require a re-tune.
The advantages of a High-Q antenna are that being so narrow banded, it does a very good job at rejecting out of band signals. I have often worked on a summit with two or three other portable operators. The High-Q of the Alex-Loop has allowed me to even share a band if I stayed at one end and they stayed at the other end, and we were only 30 yards apart. Try that with your random wires or verticals.
Another advantage of the loop is the radiation pattern. The loop exhibits a very broad radiation pattern in a figure-8 shape, with two sharp nulls. Often I have used these hulls to help block QRM coming from another direction while working others in crowded bands.
Although the Alex-Loop can be hand-held, and even tuned while holding it in your hand, after a while it does tend to get heavy. I have adapted a few tripods for working with the Alex-Loop. I have also from time to time stuck it on a Yucca Stalk, or a piece of PVC pipe tied to my camp chair.
If you are looking for a small, light-weight, multi-band compact portable antenna that is easy to set up, easy to use, and works well….. this one is for you. I see it has an average rating of 4.9. That says a lot.
Comparing the Alex-Loop Walk-Ham to the MFJ loop is just ridiculous. Of course a larger diameter loop with more skin effect will be more efficient. And also more difficult to fit in your backpack. Try putting the MFJ loop in your pack! A very unfair comparison indeed. Anyone who says they had trouble with the Alex Loop just didn’t know what they were doing, or has an ax to grind.
More recently the copy-cat ALPHA LOOP has appeared on the market. I had an opportunity to look one over. The main loop is made of several sections that need to be bolted together to form the loop. More connections just means more opportunity to have a poor connection, as aluminum does oxidize. Furthermore, stripping, losing or breaking a bolt or nut could put the whole operation at risk unless you carry spare nuts and bolts. Finally, the Alpha Loop web page is mis-leading. The Alpha Loop can be configured to work 40m through 15m, or 30m through 10m, but not 40m through 10m continuously tuned like the Alex Loop. You only learn this after reading the assembly manual. Since the prices are nearly identical, you decide.
Since I started using my Alex Loop 3 years ago, at least a dozen have been purchased by friends and SOTA operators. Not a single report of “RF burns” from anyone. And a quick check with a multimeter will show you that indeed the center and shield of the coax connector ARE SHORTED. You just need to use your multimeter to see that.
The Alex Loop Walk-Ham is a mighty fine antenna, allowing the portable ham to operate in places a wire or vertical with radials will not fit. It tunes continuously from 40m through 10m, and assembles quickly with no small parts to lose or break. If you want to build your own, contact Alex. He will help you along. But if you do not have the time, or the parts, or the skills…. or for whatever reason, the Alex-Loop Walk-Ham antenna isn’t Snake Oil. It works, and works quite well for portable operating.
If you are still unsure, trust me…. Take the chance on it. If you are truly unhappy with it, you will have no problem selling it used for only a few $$$$ less than you paid for it.
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