ad: CQMM-1

Loop On Ground Antenna

Discussion in 'Amateur Radio News' started by KD5W, Jul 18, 2021.

ad: L-HROutlet
ad: l-rl
ad: Radclub22-2
ad: Left-2
ad: L-MFJ
ad: abrind-2
ad: Left-3
  1. KM1H

    KM1H Ham Member QRZ Page

    One of my best performing 160 wires is a full size inverted V with the apex at 60' and the ends at 3'.

    On N-S paths to the Antarctic region it outperforms phased verticals and a 180' inverted V. DXpedition ops have told me Im often 10 dB+ above the pileups and Im in the log on the first call. When I first used it here after moving thats all I had up and RX was excellent but that was almost 30 years ago.
    I call that some sort of a duct and it is only into that region.

    Th same 1200W LK-500ZC amp is still in use since 1986 with the same Eimac 3-500Z's
     
    M1WML and UT7UX like this.
  2. W1YW

    W1YW Ham Member QRZ Page

    This has nothing to do with a loop antenna lying on the ground.

    A loop antenna lying on the ground induces a ground-based out of phase current from the transmission line effect.

    What you show is a lossy infinite conductor with a matching system to tap into it. There is no transmission line effect.
     
    KR3DX and M1WML like this.
  3. W1YW

    W1YW Ham Member QRZ Page

    Ground antennas are interesting but depend on resonances afforded by the geometry and composition of the below-ground layer(s). 160M is in a transition region where the effects can be good, but are less universal than at ELF, for example.

    This is not crazy stuff, just subject to location.
     
    KR3DX and M1WML like this.
  4. K3RW

    K3RW Ham Member QRZ Page

    Now I can do my 2200m antenna--LoG! Its gonna look like a mouse maze though
     
    M1WML likes this.
  5. MW1CFN

    MW1CFN Ham Member QRZ Page

    Why are so many people on here quick to anger? If you READ the post, I wrote:

    "I wanted to have a go at a 'ground loop', which is a little different ".

    The point being that, whilst it has a different means of operation, it is an alternative small plot solution for 160m - as the words:

    "but still a large-antenna-in-small-space installation"
    indicate.

    As always, nobody forces you to read a post, or to respond to it. I didn't claim it was the same antenna. I clearly provided it to anyone who hasn't embarked on 160m for lack of space as a possible solution. I'm sorry if you can't identify people trying to be helpful.

    Maybe you can complain to QRZ.com that the above constitutes a 'political post' or something? You can then have it deleted. Yeee harrr!
     
    WB0DVM, GM4JPZ and M1WML like this.
  6. W1YW

    W1YW Ham Member QRZ Page

    Post #47 has zero anger content.

    It is important to not digress from topic. You assert anger when , in reality, you are confusing provision of information with emotion.

    Your antenna has nothing to do with the LOG discussed here. A so-called LOG antenna is a loop laying on the ground, exciting phase cancellation via the transmission effect from the ground.

    Your antenna is attempting to make the ground radiate.

    Not the same, is it?

    Are you asking us, by analogy, to conflate COAX with an ANTENNA (itself)?

    Fact.

    Not anger.
     
    Last edited: Jul 23, 2021
    KR3DX and M1WML like this.
  7. N1IPU

    N1IPU Ham Member QRZ Page

    If you live in an apartment or HOA before you resort to on ground antennas get rolls of copper foil tape. Run it along the walls at ceiling height and it can be painted over once it s done. Add a short length of coax and your good to go. Next is magnet wire. Use your imagination. Also try 2 conductor thermostat wire. You can run in in places exposed under certain circumstances. Maintenance guys rarely bother checking what its for. I ran a loop in a large attic and dropped it down the pipe chase to my place.
    Honestly most of the unwashed masses haven't a clue.

    Really just use your imagination. Be a resistance agent and conduct your mission.
     
    KR3DX, M1WML, UT7UX and 2 others like this.
  8. MW1CFN

    MW1CFN Ham Member QRZ Page

    Not anger. But a narrowness of mind so incredible as to even put the US to shame. It's about small lot antennas. That was part of the whole ethos behind the OP. Here are the opening words:

    "Always looking for good antennas to use in HOA"

    No digression, and I don't take instructions from you. Sorry about that, but you'll just have to fall in line and be one of the crowd, like everyone else.
     
    M1WML likes this.
  9. W4EAE

    W4EAE XML Subscriber QRZ Page

    I have used this antenna, and it has worked as promised as a receive antenna (lower signal level, but also lower SNR). I even used it with a very wide tuner to check into an 80m net in a pinch.

    I seriously doubt that with would be the best possible RX antenna in every situation; but if you have no way of supporting an elevated horizontal loop, it can be very useful.

    Modeling is an excellent tool, but it is not the be-all end-all. There are simply too many factors specific to a given installation to take into account, and these factors can vary greatly. If you have tried it and it didn't work for you, don't use it. If you haven't tried it, give it a go. It is cheap and easy, and you may be pleasantly surprised. :)
     
    M1WML, KK9W and MW1CFN like this.
  10. AA4MB

    AA4MB XML Subscriber QRZ Page

    I have a toolkit. My medium blade sized flathead screwdriver is (overall) a very poor substitute for a Phillips head. Sometimes, however - it works better when I don't have the proper Phillips head number screwdriver. It's hard to argue with performance - or your ear. We used to call RFI the 'frying pan noise' when I was a Novice. I'd do almost anything to lessen the chance of having to listen to that in the background. Personally, given the real world audio and not looking at the scope, I'd take the LOG any day over most of those signals in that particular comparison.

    It's just an antenna switch away from being another thing in his existing 'toolkit' and as such, I find it hard to fault.

    - Matt, AA4MB
     
    M1WML and KK9W like this.
  11. KO2Q

    KO2Q Lifetime Member 562 Platinum Subscriber Life Member QRZ Page

    If everybody laid their antennas on the ground I'd finally have better luck in the contest.
     
    N5YPJ, F1LPT, KR3DX and 8 others like this.
  12. WA6VVC

    WA6VVC Ham Member QRZ Page

    Antennas... working all the angles. Here's one we use for Low Probability of Detection. I call on the "Gopher Tenna" Roll it out on the ground to get comms up. 2-65 mHz, 200 Watts.

    Look up Eyring low profile antenna, ELPA, model 302A. Eyring Research Institute, Inc. > https://patents.google.com/patent/US4825224A/en

    The manual > http://hflink.com/antenna/elpa/ELPA_302A_Manual.pdf

    Other good stuff > https://radionerds.com/index.php/ELPA_302A

    LOTS of ARMY tactical antennas, etc.

    https://books.google.com/books?id=umsqG25z-_sC&pg=PA19&lpg=PA19&dq=eyring+elpa+antenna+patents&source=bl&ots=0QgjWtIsGW&sig=ACfU3U3WCnnVuDyv1y_NWpyEjUPLNTZisA&hl=en&sa=X&ved=2ahUKEwiGi47Wi_rxAhUPv54KHWZBBPEQ6AEwB3oECA0QAw#v=onepage&q=eyring elpa antenna patents&f=false

    NOT a DX Commander, but in command...LOL

    It works. WA6VVC / WA6CAM

    ELPA 1.jpg ELPA 2.jpg
     
    Last edited: Jul 23, 2021
    G0OIL, M1WML and MW1CFN like this.
  13. WN1MB

    WN1MB Ham Member QRZ Page

    W1YW should get in contact with Eyring and enlighten (chastise) them about how poor their antenna is.
     
    M1WML likes this.
  14. WA6VVC

    WA6VVC Ham Member QRZ Page

    Sometimes tripping thru the tulips...it ends up looking more fractal than what the manual shows. LOL

    I'll pass that up the chain.......

    WA6VVC / WA6CAM
     
    M1WML likes this.
  15. UT7UX

    UT7UX Premium Subscriber QRZ Page

    Tried to simulate something similar with MMANA. Assuming the antenna is symmetrical and has two halves both approx 115' I'd have to ask you how you feed it as at given height MMANA says it could have some 10 Ohm impedance (w/o any match SWR will be 5.0 at resonant freq). One of obvious solutions: move feedpoint off center. Anyway this is true NVIS antenna with maximum gain directed to zenith.

    Inv.V.160.jpg

    Code:
    Inv. V 160m 60'-3'
    *
    1.84
    ***Wires***
    3
    -1.712e-15,   0.1,   14.941748,   -1.712e-15,   -0.1,   14.941748,   0.001,   -1
    -1.712e-15,   0.1,   14.941748,   4.599e-16,   35.556715,   0.69064,   0.001,   -1
    -1.712e-15,   -0.1,   14.941748,   4.599e-16,   -35.556715,   0.69064,   0.001,   -1
    *** Source ***
    1,   0
    w1c,   0.0,   1.0
    *** Load ***
    0,   0
    *** Segmentation ***
    400,   40,   2.0,   2
    *** G/H/M/R/AzEl/X ***
    2,   0.0,   0,   50.0,   0,   0,   0.0
     
    M1WML likes this.

Share This Page

ad: Radclub22-1