We seek to understand and document all radio transmissions, legal and otherwise, as part of the radio listening hobby. We do not encourage any radio operations contrary to regulations. Always consult with the appropriate authorities if you have questions concerning what is permissable in your locale.

Author Topic: Square or Bent Dipole for Transmit  (Read 854 times)

Offline bandarr3000

  • Sr. Member
  • ****
  • Posts: 314
  • Grand Rapids, MI
  • Can't have everything. Where would I put it?
    • View Profile
    • Email
Square or Bent Dipole for Transmit
« on: June 10, 2018, 0002 UTC »
Has anyone ever used a single band dipole, or maybe even a G5RV (or it's Jr.) in a horizontally square configuration for transmitting?  How about horizontally bent?  I'm trying to get close to omnidirectionality while using an ideal space in my yard.   An inverted V is an option, but I want to specifically find out if the "square dipole" will work.  Thanks in advance.
Yaesu FTDX3000D
SDRPlay RSP1A
W6LVP loop antenna
EFHW 40-10 as inverted L
Grand Rapids, MI

eQSL please to bandarr@gmail.com

Offline ThaDood

  • Sr. Member
  • ****
  • Posts: 314
  • There
    • View Profile
    • Extreme Part #15!
    • Email
Re: Square or Bent Dipole for Transmit
« Reply #1 on: June 10, 2018, 0141 UTC »
Well, not technically what you are looking for, as far as single band dipole goes, but I'm getting good results using an Inverted-L antenna from MW up to 17M. So far, I can tune up 160M, 80/75M, 60M, 40M, 30M, 17M, 15M, 12M, 11M, and 10M, with it with an antenna tuner. It seems pretty OMNI. I've QSO'ed in all directions and have not really noticed a hot spot direction, or a null. I am using a 4:1 W2DU current balun with it. When I think about it, my 6M Halo antenna is a dipole wrapped around as a loop, and that's OMNI. Don't know if that answers your question though.
I can't decide upon what's worst, young and stupid, or old and chemically dumbed down.

Offline RobRich

  • Sr. Member
  • ****
  • Posts: 347
  • Tampa, FL USA
    • View Profile
Re: Square or Bent Dipole for Transmit
« Reply #2 on: June 10, 2018, 1429 UTC »
It is typically feed different than a dipole, but you are essentially describing a square halo. Take a look at a Cushcraft Squalo for example.

You might also be interested in looking at a 1/2-wave halo for ideas.

https://en.wikipedia.org/wiki/Halo_antenna
Tampa, FL USA | US Map Grid EL88
Kenwood R-600 + R-2000 | 2x RTL-SDR V3 | Si-Tex 200 | Soft66LC4 | Yaesu FRG-7
Ameco PCL-P | MFJ-784B | MFJ-901B | 2x MFJ-1020B | 2x Timewave DSP-9
148' "Shielded" Loop-on-Ground | 18' End-Fed Vertical | 9' + 31' Verticals

Online Josh

  • DX Legend
  • ******
  • Posts: 3409
    • View Profile
Re: Square or Bent Dipole for Transmit
« Reply #3 on: June 10, 2018, 1701 UTC »
Linearly loaded antennas usually work out just fine.
Conveniently located near Vincennes Indiana.

Offline JimIO

  • Sr. Member
  • ****
  • Posts: 369
  • QTH I.O. MA
    • View Profile
Re: Square or Bent Dipole for Transmit
« Reply #4 on: June 10, 2018, 1826 UTC »
What band, 43M? A Moxon Rectangle  pointed up would probably work good for NVIS.

Offline ThElectriCat

  • Full Member
  • ***
  • Posts: 101
  • Hillsboro OR
    • View Profile
Re: Square or Bent Dipole for Transmit
« Reply #5 on: June 11, 2018, 1707 UTC »
I Have tried what you are talking about, I think. When I First got on HF ham radio, I was confined (or so I thought) to 40 meters and up, due to the size of my parents yard. I really wanted to get on 80 meters, and, not having any real experience, I tried almost everything. Bending the ends of the dipole in the same direction to make a 'C' shape, failed to tune, and I have no idea what the pattern was, as I was never able to transmit on it. After some reading, and help from a friend, I tried a 'Z'shape. The feed point was in the center of the 'Z', with each end bent in opposite directions. This was also somewhat of an inverted vee. I had the feedpoint about 40 feet up on some 1.5 inch steel EMT tubing which I had welded end to end, the bends in the 'Z' were about 20 feet up supported by trees, and the ends were about 10 feet up. The antenna was a little harder to tune than my 40 meter inverted vee, but would load up well, and seemed to work well in all directions. It was no larger than the "'C' shape, but significantly better. Something to keep in mind, the bending of the legs into a 'Z' shape will detune the antenna, so if you are operating on a single frequency, and wish to not use an antenna tuner, give yourself plenty of extra wire, and tune the antenna in its final position, also, the less bend you can get away with, the easier tuning will be.
In another life, I could have been a telephone engineer.

Offline JimIO

  • Sr. Member
  • ****
  • Posts: 369
  • QTH I.O. MA
    • View Profile
Re: Square or Bent Dipole for Transmit
« Reply #6 on: June 11, 2018, 1823 UTC »
I only built one for TV channel 11 (201 Mhz). Being all or nothing digital TV you could still tell it had gain in the direction it was  supposed to. The dimensions are pretty critical. Check here.

http://www.tippete.net/cgi-bin/moxgen.pl