Review: 6m, 2m & 70cm Horizontal Loop Antennas by eBay Seller Freqtester

Discussion in 'Amateur Radio Equipment Reviews' started by W2WDX, May 19, 2018.

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  1. W2WDX

    W2WDX Subscriber QRZ Page

    Hi all,

    It's not often I get excited about an antenna manufacturer. Most designs always leave something to be desired either mechanically or performance wise. Many times antenna manufacturers compromise structural integrity for ease of assembly; or they use materials that are not compatible which lead to undue corrosive issues. Many times the performance is grossly exaggerated. Sometimes the voodoo magic claimed borders on the level of type of rhetoric you find in high-end home audio marketing. I have found one exception ... freqtester.

    Here we have an eBay seller. And one who has been selling the same basic design for many years now. First, he is a Ham (albeit I have yet to find out what his callsign is). He also is a machinist by trade. His products reflect this. I purchased some of his antennas many years ago, and use them all the time in some of the worst environments you can install an antenna. Namely, near the Atlantic Ocean shoreline of New York. Salt air, noreasters and hurricanes, high-winds, extremes in temperatures to name a few. These antennas deal with all of this very well. And the performance remains consistent year after year. At this point I have tried and tested all of his offerings, and used them in many different environments.

    First let me state, my comments on these fine antennas are subjective, anecdotal and strictly observational. I have never tested these on an analyser, measured on a FS meter or tried modeling them. So keep this in mind.

    Freqtester and his antenna products can be found only on eBay. I think this keeps his products at a lower cost and makes it easy for him to sell online. At this point it looks like he has sold thousands of these antennas and has a perfect 100% rating on eBay. (That does say something).

    2mloop.jpg 2mcircloop.jpg
    6mloop.jpg

    Currently at this writing he offers six models of VHF/UHF horizontal loops. They are for 6m, 2m and 70cm, in both square and circular variants. They are constructed entirely of good quality 6061 aluminum. Machined parts are simple and well fashioned. All hardware is stainless steel. The 2m & 70cm loops are solid rods for the elements, the 6m is made from 7/8" tubing. The matching uses a typical gamma configuration on all. Phasing kits for stacking is also available. You can also purchase complete pairs with phasing harness included for each model. All can accommodate up to a 1.5" mast. All of the antennas are optimized for use in the SSB portion of each respective band, however tuning for other portions is easy and straight forward and the antennas have a fairly good bandwidth anyway.

    Power handling is between 800-1000w IACS for individual antennas; more when stacked. And I can attest to this fact since I have run as much as 2KW PEP into stacked pairs with no problems. Stacking these does seem to improve gain and improve the low-angle pattern. Gain on these antennas is claimed to be 3-5db (depending on height) for individual loops; which seems to be about right. Stacked pairs increase this slightly by a few db.

    Noise on receive is an important issue that should be dealt with on weak signal SSB on 50mHz and above. Horizontal loops are by their nature very low noise, even when compared to horizontally polarized Yagi's or even dipoles. So using horizontal loops for receive on weak signal work or VHF/UHF DX is a good idea. I use mine when calling CQ to listen omnidirectionally for stations coming back. Once I make contact I get a bearing and spin the Cushcraft yagi. The use of these low noise loops, especially when stacked, give me a good edge on being able to pick out stations quickly.

    I have used these antennas mounted on masts atop a typical suburban home, on top of a 5 story commercial building with a steel roof, and atop a 24 story apartment building in an urban environment. In all cases performance was fairly equal and consistent; with the expected additional reach on the tallest buildings. They have survived hurricanes (Sandy), numerous noreasters, and salt air exposure with minimal corrosion and no mechanical damage. Manmade noise in these environments can be very high; however, as expected these horizontal loop are very effective at rejecting these types of noise sources.

    These antennas seem to work best when mounted on a well grounded metal mast, even when stacked. Ease of tuning and bandwidth is improved when mounted this way. Although I have mounted these on fiberglass masts with marginal impact. running a ground wire to them in this application takes care of this minor issue and improves safety.

    Another nice thing is that each antenna come fully assembled and tested, even the larger 6m loops. They even include the allen key for making adjustments if any are needed.

    I use these with a good SHF mast mounted preamplifier (on a sequencer) which really helps pull in weak signals due to the low noise nature of these antennas to begin with. The signals come up, not the noise. This is something I highly recommend. Also they do work just fine to hit local repeaters, albeit not as well as a vertical or a vertically polarized yagi for more distant repeaters. They also are small enough to fit inside most attics (although I have not tried them in this application), great for you HOA challenged Hams.

    As far as the difference between the circular or square versions; I see no difference in performance between the two and you can pick them based on appearance only.

    If I had one criticism (and I have none other than this) it would be a lack of corrosion inhibiting. They do get that nasty coating of aluminum oxide when used in salty air conditions like I have here in New York. What I do is clean them with a good aircraft aluminum cleaner (such as Bonderite C-IC 33 Aero formerly Alumiprep 33) and use a clear stabilizing solution (such as Bonderite M-CR 1001 Aero formerly ALODINE 1001) afterward to inhibit any possible corrosion.

    Overall, having used all of these antennas I highly recommend them. They are high quality, easy to use, durable, come fully assembled, and perform as claimed.

    You can find freqtester and his antennas on eBay at this link:

    https://www.ebay.com/usr/freqtester?_trksid=p2047675.l2559

    See Ya, 73

    John, W2WDX

    Disclaimer: I do not know nor do I have any affiliation with this manufacturer. I just have used his products and offer this review without his input or knowledge as an enthusiastic user.
     
    Last edited: May 19, 2018
    KC9YGN and W2VW like this.
  2. K2GOG

    K2GOG Ham Member QRZ Page

    Good article. Thanks for taking the time to post this. Looks like he only has the 220 MHz version and phasing harness for sale currently. Will have to keep an eye on his store for updates.
     
  3. W2WDX

    W2WDX Subscriber QRZ Page

    Yeah ... he does production runs and goes through them fairly quickly. So bookmark the link or come back here from time to time.
     
  4. N3CI

    N3CI XML Subscriber QRZ Page

    I appreciate your posting this review of what appears to be an interesting loop antenna. I don't usually check e-bay but this antenna might be just what I am looking for. Thanks, 73. Dave N3CI
     
  5. K1ZJH

    K1ZJH Ham Member QRZ Page

    3 to 5 dB gain for a single halo/squalo????
     
  6. W4OP

    W4OP Ham Member QRZ Page

    The gain figure is obviously someone's guess. Antennas ONLY achieve gain by becoming more directive. In the case of these 'quasi' omni loops, they are less directional than a dipole- so obviously their gain is less than a dipole. NEC shows about -1.5dBd.

    They do not address common mode radiuation from the mast or the coax or of course the azimuth pattern which is typically 6dB "out of omni".
    Typically, these guys stop once they achieve a decent SWR and never address the pattern or common mode.

    Finally, antennas also become quiter (less prone to noise) by also becoming more directive- as in Yagis, Beverages, EWE, Flags etc. With that in mind it is imposibble for an omni antenna to be quieter than a Yagi. Someone did not do their homework.

    Dale W4OP
     
  7. W2WDX

    W2WDX Subscriber QRZ Page

    Someone did not read. My review is based on use, not testing. They are quieter than my former verticals of similar. Quieting is not simply only a factor of directivity; there are many variables that can make antennas quieter. You're being selective in your arguments.

    They are horizontal loops, so they are by that nature quieter since most man-made noise is vertically polarized. Horizontal polarity is also lower noise in general, but you also failed to mention this.

    CM radiation exists on any unbalanced fed antenna, so using simple ferrite chokes are normal practice, even for yagi's, on VHF. Again you're being selective.

    The gain figure is dBi referenced, since using dBd is pointless when the figure is negative; having negative figures is technically non-sequitor. Why reference gain to a directive antenna like a dipole? And at what height relative to WL?

    Admittedly, if I had a choice I would use stacked turnstiles, however stacking these antennas (granted the spacing is very critical) some gain can be achieved. Also being aware of the fact that these are small loops, not full wave or such; whereas horizontal loops are not truly omni-directional unless they are made small in terms of wavelength (which does restrict their operating bandwidth) and end loaded with capacitance to bring them back into resonance. Such antennas if stacked vertically for greater gain, must be stacked exactly one half-wavelength apart to cancel radiation that would otherwise occur along the axis of the antenna.

    Understanding the limits of any antenna and applying this knowledge will always lead to optimizing a given system. Discounting outright due to a modeling bias (without any qualifying data; like height), preferences, agendas or simply because of something you may have read or even worse being selective with your facts just to prove a point, is not beneficial to anyone. This is why I began this review with the qualifier that the review is purely anecdotal and observational. But go ahead ... by all means, impress yourself.
     
    Last edited: Jun 12, 2018
  8. W4OP

    W4OP Ham Member QRZ Page

    W2WDX:
    Horizontal loops are by their nature very low noise, even when compared to horizontally polarized Yagi's or even dipoles.

    It is impossible for a horizontal loop to be less noisy than either a Yagi or dipole. Research RDF (RX Directivity Factor). There is only one way a given antenna can be quieter than another (assuming common mode has been addressed), and that is through directivity. and is well understood in EM theory.
    At HF horizontal polarity may be quiter- this is a result of one of Maxwell's equations that states it is not possible to propagate a time varying E field parallel to a conducting surface (earth in this case). However at VHF and up where antennas are mounted many wavelengths high, it is debatable whether H is quiter than V. But that was not what I was adressing. I was addressing your quote that the loop is quieter than a Yagi or dipole.

    W2WDX:
    CM radiation exists on any unbalanced fed antenna, so using simple ferrite chokes are normal practice, even for yagi's, on VHF. Again you're being selective.

    The manufacturer does not address common mode from the coax or the mast. Because the antenna is DC ground to the mast- the mast is also a potential source of common mode. If you ask them about CM remediation, you will likely get a blank stare.

    W2WDX:
    The gain figure is dBi referenced, since using dBd is pointless when the figure is negative; having negative figures is technically non-sequitor. Why reference gain to a directive antenna like a dipole? And at what height relative to WL?

    The gain figure is still impossible. My figure of -1.5dBd is for free space. If you want it for dBi then the figure is
    +0.6dBi. BTW, negative antenna gain figures are very commonly used. Look at the gain of a Beverage or a small magnetic loop.

    W2WDX:
    Admittedly, if I had a choice I would use stacked turnstiles, however stacking these antennas (granted the spacing is very critical) some gain can be achieved. Also being aware of the fact that these are small loops, not full wave or such; whereas horizontal loops are not truly omni-directional unless they are made small in terms of wavelength (which does restrict their operating bandwidth) and end loaded with capacitance to bring them back into resonance. Such antennas if stacked vertically for greater gain, must be stacked exactly one half-wavelength apart to cancel radiation that would otherwise occur along the axis of the antenna.

    The gain vs stacking distance for loops (or turnstiles) is not critical. Changing the stacking distance at 2M from 4' to 6' changes the stacked gain by less than 0.1dB.
    There are designs that are 'small' yet have excellent omni pattern. Reference:
    http://www.parelectronics.com/omnis.php
    These antennas were designed using pattern synthesis and are within +/- 0.5dB of being a perfect omni and better than the turnstile or big wheel. Common mode from the feedline and mast have been addressed.

    Why is cancelling the lobe through the axis so important? Yes, that happens at 1/2 lambda but the goal in amateur stacking is maximizing gain (s you stated)- that occurs for 'loops' at distances considerably greater than 1/2 lambda.

    I stand by my statement- these guys making square and round loops stop once they achieve a low SWR and never investigate pattern or common mode issues. Ask the MFG if he has measured or even modeled the pattern. We do agree on one thing- the mechanical design is very nice.
     
  9. W2WDX

    W2WDX Subscriber QRZ Page

    Look ... great. I'm glad you know a thing or two. But you have totally missed the point. These antennas are inexpensive, easy to use, and in my experience perform just fine. You can always debate that there are better antennas compared to any antenna. And that's an old and IMO pointless debate with no meaningful outcome. That is not the point of a review. You can exercise your knowledge in other forums (like the antenna forum), but that is not the point of this forum.

    We could debate the Parelectronics, and I can show you a paper that says it performs poorly. (I think it's fine BTW). I never said these are quieter than yagi's or dipoles. What I said is horizontal antennas are quieter in general. The majority of Hams use vertical omnis on 2m and 70cm, which is where the comparison lies by inference. Again debate or knowledge challenges is not the purpose of a review forum.

    In my years of experience using these antennas, my opinion is that these antennas work well, do what they claim at least observationally, are easy to setup and use, are tiny, and are made well. And that's the point of a review. It's about context and experience, not technical prowess or even a comparative study in the case of this review. I simply offered an option.

    Don't ask me about my experience with OCF dipoles and bazookas ... that would be all negative, and I'm a positive person! hihi.
     
    Last edited: Jun 12, 2018
    KD2NOM likes this.
  10. W4OP

    W4OP Ham Member QRZ Page

    I would be interested in the paper on the Par antenna, if it is done by a professional. From what I see, it is a very thorughly vetted design- reviewed by CalTech and type accepted by the RFID industry, and hundreds of 5/5 on the review sites.

    We agree on the bazooka. Despite it being exposed by luminaries such as Frank Witt (IEEE Honorary), Maxwell and Owen Duffy, hams continue to use them. The most common argument I hear is that it was developed at MIT- so it must be good. While the MIT part is true, no one seems to read that in their UHF design, the coaxial stubs were 12 Ohms. At that low Z, there is indeed some reactance cancellation and the stubs were air dielectric. Today's design achieves its bit of BW increase from loss in the stubs. Claims of gain, quieter and does not need a balun are just more of the hype. But you undoubtedly already know that.
     

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