LOOP fed yagi 4 element 6 meter HY-GAIN Loop fed array

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  • Опубликовано: 27 янв 2025

Комментарии • 52

  • @DonDegidio
    @DonDegidio 7 лет назад +1

    Eric,
    When I had my tribander down for servicing, I installed a Comet CA-52HB4 4 element 6M wide band yagi. It has less than 2.1 VSWR across the whole 6M band. Haven't made any contacts, yet. Hoping to make some during the contest. Another point is to seal all the coax to element joints. I found that liquid tape works great. Three layers gives a thick coating. The Comet is located about 9 ft above the tribander and 8 ft below a dipole made from two Hustler MO2 masts and the tri-resonator accessory for resonators on 80, 40, and 20M. All mounted on a Wilson TT45 tubular tower rotated with a Hy-gain T2X. The Comet sits about at 40 ft lowered and 55 ft when the tower is raised. Forgot to install a balun. I'm making mine out of ferrite beads and will put them on next time I lower the tower to the ground. I'm using the same radio as yours. 73 WB3BJU

  • @justanotherguy3850
    @justanotherguy3850 7 лет назад +1

    Thank you for taking the time to put this together, especially in the rain! It never fails. You want to put together an antenna and Mother Nature has reached a decision of her own. Here are two things I question about your installation.
    First, you didn't use a BALUN at the feed line and bring it down with some high-quality LMR 400. I would have purchased a ferrite 1:1 BALUN. They are inexpensive. As you know, the purpose of the BALUN is to eliminate the RF coming off of the coax and once you factor in putting on a PL259 and then using a coupler and then another PL259 you've already spent as much money as you would have on a choke BALUN and you have insertion loss that needs additional weather sealing. Another approach would be to take about 12 chokes and slide them over the coax along with a piece of heat shrink to hold them in place. you may use some black zip ties to further hold them in place. You use black to minimize UV breakdown of the zip type.
    Second, remember that current flows on the outside of the conductor. You used single strand coax and simply ran a loop around a nut and bolt. For the maximum transmitted power which may seem miniscule to some but you want to use a multi stranded cable. In a strong wind and vibration that single conductor can easily snap and now you're pulling the antenna down to fix it. I would have used a crimp connector and actually soldered the wire(s) to the crimp connector. You need to weather seal them. You may have done this just to get it up in time for the VHF contest but the extra 5 minutes would have made a big difference for you with rain already striking the ground. At 50 MHz your goal is to get as much power to the transmitter as possible and as much receive down the line as possible.
    I hope that these suggestions are received with the goodwill that they are intended.

    • @HamRadioConcepts
      @HamRadioConcepts  7 лет назад

      First, i did use Hyperflex 10 Mesi and Paloni coax, solid copper standed center, double braid with copper foil, and the copper wire i used for the braid i did say solid, but it's actually stranded as well.. Check out the Hyperflex-10 coax for the specs and design... Also, the balun i do agree i should have wrapped itin a straight organized coil, which i am going to fix, but so far it has been working, no RF in the shack, but many people do not use a balun either.. Thanks for the suggestions.

    • @justanotherguy3850
      @justanotherguy3850 7 лет назад +1

      HamRadioConcepts ::Thank you for accepting my comments with the spirit that they were intended. As one ham to another. I appreciate that you use Paloni coax. I went to their website last time you mentioned it and could not find the specs on it. If it substantially improves on LMR 400 I might consider it. But I can buy half inch hard line for a dollar a foot. On 50 megahertz that's less than half a dB loss for 100 ft. Back to to-the-point, as long as your handmade BALUN is working you're all set! My preference is to use an actual BALUN from say DX Engineering. A 1:1 choke balun is $43 but I like the performance better. My bigger point that I was trying to make to you was using a single stranded center conductor coax. Current flows on the outside of the conductor and you get a better flow of your RF power using multi-conductor coax. Just as important, if you have winds kick up and break of the single center conductor guess whee pulling the antenna down? LOL. I'll come to watch. At a minimum I would have used a circular lug and soldered the center conductor to it and then wire tied it down so that even a little bit of play wouldn't snap the center conductor. I would also use paint on tape that would seal the crimp lug from all moisture.
      I hope you're not reading this instead of actually playing in the VHF contest! Let us know how well the antenna has done on 6m and if there was even an opening. It is 7:30 a.m. here in Southern California at 6300 feet where I live and 6m appears dead on a dipole. WWV at 10 MHz was at 9 with a lot of noise. Great video!

  • @mdblack98
    @mdblack98 2 года назад

    We (WA1SXK and W9MDB(me)) recently tuned a Cushcraft 6M4EL LFA (this exact same antenna). We were trying to tune to 50.3 primarily for FT8 work on 6 meters and ended up at 1.7 just like this video shows. We worked with the original designer of this antenna and discovered the measurements in the Cushcraft manual were wrong. We ended up at 49.5 inches on the loop (measure from center boom to outside edge of loop) and 54.25 inches on D1 (the 1st director). We did this tuning at the antenna initially with a SARK 110 analyzer to achieve zero reactance by moving the loop...then adjust resistance with D1. It was an iterative process but we now have a VSWR less then 1.1 at 50.3MHz (note that you can pick most any frequency within 200KHz or so of the center and still get < 1.1 and 50Ohms). Then we added the bead choke and 61 feet of Ultraflex 7 through an antenna switch, LPA-500, to an IC-7300 and right now shows VSWR 1.1 and +/- 300KHz to VSWR 1.5. Several things we learned....
    Do not tune your 6M beam at the rig...the common mode will mess up your measurements. Also do not try and tune using VSWR -- you'll just get yourself wrapped around the antenna trying to adjust it (VSWR hides what you need to adjust).Tuning can be mostly done on the ground with the antenna tilted up and at least 3 feet off the ground. Raising the antenna further will make some small changes (like increasing the tuned frequency) which you can adjust again if you want to improve the measured VSWR. Your goal is 50Ohms, and j=0. When you add your coax and rig you will get some change since nothing is ever exactly 50Ohms plus you pick up effects of the cable...but the tuned point (j=0) should remain no matter the length of the cable if the antenna is tuned close to zero reactance and 50Ohms (VSWR < 1.1). Once you hook up your coax DO NOT ADJUST THE ANTENNA ANY MORE. Any more antenna adjustments will lie to you at the rig due to common mode effects. You already tuned the antenna. Changes in coax length will effect the non-resonant portion of the 6M band but a tuner should be able to handle that to make the rig happy. We also found that rain no longer affects the VSWR at the tuned frequency. It will affect VSWR on non-resonant frequencies. Note that resonance is J=0 and not minimum VSWR and is why you can't tune using just VSWR.

  • @Too_Many_Hobbies_UT
    @Too_Many_Hobbies_UT 7 лет назад

    I installed the same Hy-Gain LFA4 antenna on May 1st and have been using it quite a bit since then. I was actually the first customer to get this antenna from Hy-Gain. The issue I had was the first director (2nd element from the front) was too short so I had to slide out the larger diameter piece further from the boom to make the measurements correct. I also ordered a bag of #4 hose clamps and double clamped everything. I am happy with the performance of the antenna and have powerline noise issues as well and it is VERY apparent when I rotate away from the noise. I feel the F/B ratio and low noise claims are completely valid with this antenna and I strongly recommend it. As somebody else mentioned, I would recommend re-doing your choke to make the coils side by side and see if you can do a better job of connecting the coax to the driven elements.
    Nice job producing the video and sharing your experience!!!

  • @russramirez5672
    @russramirez5672 7 лет назад +3

    The SWR is measured on the RF final side of the internal tuner, the analyzer sees just the feed impedance.

  • @TheLightningStalker
    @TheLightningStalker 5 лет назад

    If there is another length of coax between the RXTX and the feedline that isn't there when you connect the MFJ, it will give a different reading. This is because of nodes along the cable caused by mismatch at the antenna. You can either just not worry about it or use a matching stub or some other matching scheme at the antenna. I'm no expert but that is that is the most accurate description based on what I have read.

  • @TM10E
    @TM10E 7 лет назад

    I have the same problem with an $400 SWR meter, compared to my newer ICOM radio. I think it is the resonance the cable in between the radio and the SWR meter. I tried 2 other meters, and they both read high. I changed the cable length between the radio and the meter and I was able to make them match - not sure what is accurate however! Like to see other comments on this subject, as I have seen this more often than not at other friends setups.

  • @techiefan1986
    @techiefan1986 6 лет назад +1

    Have you tried more vertical separation between the VHF and 6 meter yagis? I think 10ft seperation would be the most ideal (1/2 wavelength of the lowest frequency)..

  • @chesty1369
    @chesty1369 7 лет назад

    I have the same MFJ analyzer. I have noticed when I am around certain devices it will pick up local EMI. See is you get the same results if you ground it or move it away.

  • @bigchew3149
    @bigchew3149 Год назад

    I was told by a Extra that runs a repair shop To Never Trust a Radio's SWR Meter he says they are Almost Always Wrong ! But I dono ! ! I believe him ! But To Each Their Own !

  • @우승웅
    @우승웅 5 лет назад

    If your coaxial feed cable is long, attenuation by the coax may be the cause of two different SWRs measured at two different location, your Rig and ANT feed point. Because the reflected wave is attenuated by the coax during the round trip back to your rig. from 6M0MM, Woo

  • @kenwood9401
    @kenwood9401 3 года назад

    the problem is both drop 2 meter lower the rf choke should be 15 turns on 6 inch al my antennas have the same choke and running 1.1 on all

  • @KA4UPW
    @KA4UPW 4 года назад

    Use a current balun, put the 6m beam at the bottom of the mast and the 2m at the top, increase the spacing to 1 wave length @ 2m

  • @rcelectronicsllc9400
    @rcelectronicsllc9400 4 года назад

    Listen for the MFJ analyser on the radio. Could be the frequency on the MFJ is not exact.

  • @tonyridlen
    @tonyridlen 6 лет назад

    Excellent video about a 6 Meter antenna set up!!! KC9QVE Gas City,Indiana

  • @lexheath8276
    @lexheath8276 4 года назад +6

    MFJ used to make good stuff. I've had nothing but trouble with their products in the past ten years.

    • @JxH
      @JxH 2 года назад

      I disagree with this part: "MFJ used to make good stuff."

  • @apetercharlesstudio
    @apetercharlesstudio 6 лет назад +1

    The choke balun is NOT a impedence matching device.
    To match a yagi's feedpoint, you need a 1/4 wave stub, Pawsey etc.
    Also, the length of the coax center conductor and shield should be as short as possible as they behave like radiators.
    It is possible to achieve a 50 ohm match with a Yagi, this is needed if one desires to have maximum power transfer from source to load.

    • @joeh3767
      @joeh3767 4 года назад

      The LFA yagi has a feedpoint imedance of 50 ohms. One of the LFA benefits.

    • @apetercharlesstudio
      @apetercharlesstudio 4 года назад

      @@joeh3767 True, there are however 3 possibilities when presenting the antenna with 50 ohms. Inductive, reactive and resistive. It is the latter you want at the feed point. You can have a nice swr and still waste power if it's a combo of reactance & resistance or a combo of all three types of loads. The Pawsey stub if measured properly will give the feedpoint a resistive load. If you have a antenna analyzer, have a look. Few antennas present a pure resistive load without some type of impedence matching. Many hams confuse a good match with low swr where power is often wasted in reactance, inductance or both. Look up a Pawsey stub. I run a 5 ele LFA on 6. My field radiation AND pattern are much better with the stub.

    • @joeh3767
      @joeh3767 4 года назад +1

      @@apetercharlesstudio Good clarification. Owen Duffy has a nice piece on this.

    • @apetercharlesstudio
      @apetercharlesstudio 4 года назад

      @@joeh3767 He sure does as well as others. The cool thing is a 6m stub is beautifully simplistic. Rather than coax for my stub. I used a 1/4 wave piece of stainless. Just kept making small cuts till the analyzer showed I/C were minimized.

    • @jimeppright7862
      @jimeppright7862 3 года назад

      @@apetercharlesstudio Suggest you check out SS loss at 50 mHz. K5RX

  • @marknormankn4cwt619
    @marknormankn4cwt619 7 лет назад +1

    Are you using a new camera? Video quality is great.

  • @glevideo
    @glevideo 4 года назад

    Supposedly the feed point on this antenna with the full wave loop feed is 50 ohms. Take a look at this video where this guy shows how to make this antenna (3 part video) ruclips.net/video/p2ajOTwvx4Q/видео.html

  • @robertspicer7477
    @robertspicer7477 7 лет назад

    First I would redo your coaxial choke,the turns need to be side by side do not let the turns overlap,wind it on a round form.2 it would benefit you to put the 13b2 above the lfa and get as much separation between the two as you can.The coil is not actually a balun it simply acts as a high impeadance to keep rf from coming back down the feed line and distorting the pattern.Good luck this weekend and hope to hear you. VA6PPZ

  • @w0jwjohn680
    @w0jwjohn680 7 лет назад +2

    Probably the spacing is causing your readings. If you look at the directions of your antennas they will state the stacking distance of like antennas. If memory is correct the 13b2 needs something like 9 1/2 feet between it and another 13b2. And the 6 meter antenna is probably going to need something like 11 feet. So, I wonder if your readings changed on the 13b2 after putting the 6 next to it ? Now I'm not saying you won't be able to make contacts the way you have it but the 2 antennas are differently seeing each other. There are some good websites about antenna stacking but the bottom line is do the best with what you got and have fun. 73 W0JW

    • @HamRadioConcepts
      @HamRadioConcepts  7 лет назад

      Yah, the best with what i got, or else i would have them on different towers OR seperated more.. But hey, already landed a couple 6 meter contacts that normally only look like S1-2, he was S9+10

    • @w0jwjohn680
      @w0jwjohn680 7 лет назад

      OK, thats great. Now check out jt65 and msk144 on 6 and go get them grids.

    • @HamRadioConcepts
      @HamRadioConcepts  7 лет назад

      Well, I am familiar with JT65, didn't use it long.... I love weak signal modes and QRP, but i guess 6 meters might give me the itch to try JT65 again. It's kind of slow.. But now it's like trying it all over again. Is PSK active on 6?

    • @w0jwjohn680
      @w0jwjohn680 7 лет назад +3

      Not much psk. Check out WSJT software for meteor scatter. physics.princeton.edu/pulsar/k1jt/ This will open up your fun. This software is also used for EME. I've made 4 DX EME Q's with a 13b2 and 100 watts. You just got to find the big gun stations, but it can be done . look up wsjt ,meteor scatter and eme on youtube.

  • @tonyridlen
    @tonyridlen 4 года назад

    Fascinating 6 Meter Magic Band Presentation Video! KC9QVE AMATEUR EXTRA Marion,Indiana

  • @tonyridlen
    @tonyridlen 4 года назад

    Could you in the future show ham radio youtube viewers you participating in the ARRl VHF QSO Party so we can see 6 Meter activity at it's finest peak and plateau point? Anthony O.Ridlen KC9QVE AMATEUR EXTRA MARION,INDIANA OVER AND OUT!!!!

  • @MultiKhanon
    @MultiKhanon 2 года назад

    อยากได้

  • @jodylaneyAA4XT
    @jodylaneyAA4XT 6 лет назад

    Radio stations close by can make antenna analyzer give bad reading

    • @warplanner8852
      @warplanner8852 6 лет назад

      No, they won't.

    • @jimeppright7862
      @jimeppright7862 5 лет назад

      They certainly can, but not likely to on 6 m. It is very common on 160 m. with nearby AM BCB stations. 73, K5RX

  • @bills1613
    @bills1613 7 лет назад +5

    Put new batteries in your analyzer and recheck the standing wave, seriously.
    Mine gives screwy readings when the batteries get low, sometimes even just a little low and it gets screwy.
    And dude, just keep your yagis (ssb yagis) horizontal the way God intended, not some gimmicky half/half so you get "some" of both. You didn't purchase, assemble, and install an expensive high gain antenna just to half-ass the whole thing. When you have a yagi you are trying to optimize not half-ass. Dont listen to that silliness. By doing that 45 degree silliness you are compromising your performance by several dBs and much clarity and just blowing your whole intention. You're just shooting yourself in the foot and wasting your money and a damn nice antenna. If you cock it over like that you might as well just put up a 3 element horizontal yagi for SSB (which I actually use right now on 2M and does surprisingly well) and a small vertical for FM because that's basically what you're getting by compromising your high gain yagi in that way. So just leave your yagis horizontal for SSB and mount you a nice colinear vertical (if you're wanting gain) on the corner of your house for FM , a nice Comet or Diamond they work extremely well, you'll be surprised how well they work and go from there.
    Good luck this weekend,
    KF4PCT

  • @a9beam434
    @a9beam434 6 лет назад +1

    Its not the spacing Remove the small pice of ground wire that you added to the shield coaxial cable
    Adel Eid A92FF

  • @johncliff5417
    @johncliff5417 7 лет назад

    I was just getting seriously interested in your video and suddenly your WX changed to our British summer time WX. Sorry but I just fell about in laughing. Hi Hi. Call it Sods or Murphy's law. What do you in the states call "Dog gone" or something like that. Carry on regardless. Just hope it don't get into the jointing sections and cause corrosion. Well any how good Dxing on 6m. 73 de John - G0WXU.

  • @samselectronic4548
    @samselectronic4548 7 лет назад +1

    iv got 20 year's in on 6, and 25 with the state, your radio is seeing the swr off your analyzer not ant, same as it would if you was running a amp, and check you spacing on ant, 73's

    • @clems6989
      @clems6989 7 лет назад

      His analyzer isn't connected between the radio and antenna is it ??

    • @samselectronic4548
      @samselectronic4548 7 лет назад

      Yeah you have a jumper from your radio to your analyer, your radio is only looking at the swr bewteen radio amplifier or swr meter, that why you have a turn input on amplifiers

    • @lonmartinlonm6409
      @lonmartinlonm6409 5 лет назад +1

      @@HamRadioConcepts Yeah...is he saying that after 20 years on 6 meters, he's worked only 25 states?

    • @lonmartinlonm6409
      @lonmartinlonm6409 5 лет назад +1

      @@clems6989 MFJ analyzers don't have an input AND an output, so it's impossible to connect it between two devices.