Page 1 of 2 12 LastLast
Results 1 to 10 of 11

Thread: 3/2 wave dipole

  1. #1
    Witch Doctor
    Join Date
    Apr 2010
    Posts
    387

    3/2 wave dipole

    Post Deleted
    Last edited by WN9HJW; 08-03-2013 at 09:09 AM.

  2. #2
    "Island Bartender" KG4CGC's Avatar
    Join Date
    Mar 2007
    Location
    EM84ru, Easley SC
    Posts
    51,304
    Tell them it's a 3rd of a wavelength over a half wave dipole ie; operating in colinear mode.
    If you can't dazzle them with sparkly baubles, baffle them with Bullshit.

  3. #3
    Administrator N8YX's Avatar
    Join Date
    Feb 2007
    Location
    Out in the sticks
    Posts
    26,087
    Make the top section 93ft overall, change the ladder-line length to around 44ft and get coverage of 40-20-17-12-10M with <2.1 VSWR. Feed with 1:1 current balun and LMR400 or better to the radio. I use RG-213 with mine.
    "Everyone wants to be an AM Gangsta until it's time to start doing AM Gangsta shit."

  4. #4
    Whacker Knot WØTKX's Avatar
    Join Date
    Aug 2008
    Location
    Lakewood, CO
    Posts
    26,758
    Doublet.
    "Where would we be without the agitators of the world to attach the electrodes
    of knowledge to the nipples of ignorance?" ~ Professor "Dick" Soloman



  5. #5
    Master Navigator KC9ECI's Avatar
    Join Date
    Oct 2009
    Location
    Wiscowsin
    Posts
    1,788
    Which reminds me, I dropped one side of the G5RV to move the camper out and the boy ran it over with the mower. I sat out in the yard in front of the fire pit last night considering what to do next. I'm thinking I can convert the G5RV to a G5RV Jr easily enough, but as long as I've got it down, maybe I'll replace it with an inverted L. No particular reason, I'm just bored by the current lash-up and feel the need to try something different.
    I am surprised at such a sudden deterioration in a woman whose only ailment was a lazy anus.

  6. #6
    Master Navigator NY3V's Avatar
    Join Date
    May 2012
    Location
    Mount Pleasant, SC, 29464
    Posts
    1,555
    Quote Originally Posted by KG4CGC View Post
    ...If you can't dazzle them with sparkly baubles, baffle them with Bullshit.
    That would be stooping to the low level of Faux News and GOP diatribe. ;)

  7. #7
    Orca Whisperer W3WN's Avatar
    Join Date
    Dec 2007
    Location
    Castle Shannon, PA
    Posts
    19,353
    Quote Originally Posted by WN9HJW View Post
    When I tell people I'm using a 3/2 wavelength dipole on 10 meters, that seems to confuse a few.

    They ask things like "What is that?" or "What frequency is that for?" or "dipoles are 1/2 wavelength"

    If I say "using a 40 meter dipole on 15 meters" that seems to be OK. If I say "using a G5RV on 20 meters" that is OK.

    Maybe I should be saying "Using a G5RV Junior with the ladder line section removed and replaced with coax all the way to the radio"?

    Maybe I should just say "dipole".
    If you wish to educate them, and if they wish to be educated, you tell them this:
    Dipoles (with impedances of roughly 75 ohms) are odd half-wavelengths. 1/2, 3/2, 5/2, etc. Even half-wavelengths (1 wave, 2 wave, etc.) have an impedance approaching infinity.

    That's why a 40 meter dipole works on 15, but not on 10 or 20. (That's sans tuner/matching network, of course)

    If you don't wish to do so, or (more likely) they don't wish to learn, then just say 'dipole' and don't bother them with the details.

    ...and if it's hung as an inverted V instead of a true in-the-plane dipole, the impedance is roughly 50 ohms. And THAT is why most radio grade coax that we use is at or near one of those two impedances...
    “Nobody is going to feel sorry for us. 90% of the people don’t care, the other 10% are glad it happened.” — Clint Hurdle, 2019

    BAN THE DH!

    Fudd's First Law of Opposition: If you push something hard enough, it WILL fall down.
    Teslacle's Deviant to Fudd's Law: It goes in, it must go out.

    Just remember: Abraham Lincoln didn't die in vain. He died in Washington, DC

    Cutch 300!!!!!

    “Nero fiddled while Rome burned. Trump golfed.” — Bernie Sanders

    Quando Omni Flunkus Moritati


  8. #8
    Administrator N8YX's Avatar
    Join Date
    Feb 2007
    Location
    Out in the sticks
    Posts
    26,087
    Quote Originally Posted by NY3V View Post
    That would be stooping to the low level of Faux News and GOP diatribe. ;)
    Keep the political stuff out of the technical areas, please.
    "Everyone wants to be an AM Gangsta until it's time to start doing AM Gangsta shit."

  9. #9
    'Grumpy old bastid' kb2vxa's Avatar
    Join Date
    Aug 2007
    Location
    Lakewood, NJ
    Posts
    13,081
    "Which reminds me, I dropped one side of the G5RV to move the camper out and the boy ran it over with the mower. I sat out in the yard in front of the fire pit last night considering what to do next."

    Throw the kid in the fire pit and throw the mower in after him. With that out of the way put up the antenna of your choice.
    "The universe is under no obligation to make sense to you."
    Neil deGrasse Tyson

    73 de Warren KB2VXA
    Station powered by atomic energy, operator powered by natural gas.

  10. #10
    Banned
    Join Date
    Oct 2009
    Location
    Oregon, IL
    Posts
    7,717
    Quote Originally Posted by WN9HJW View Post
    When I tell people I'm using a 3/2 wavelength dipole on 10 meters, that seems to confuse a few.

    They ask things like "What is that?" or "What frequency is that for?" or "dipoles are 1/2 wavelength"

    If I say "using a 40 meter dipole on 15 meters" that seems to be OK. If I say "using a G5RV on 20 meters" that is OK.

    Maybe I should be saying "Using a G5RV Junior with the ladder line section removed and replaced with coax all the way to the radio"?

    Maybe I should just say "dipole".
    I am assuming the 3/2 dipole is around 52 feet long then? Where do you feed it?

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •