1. You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.
    Dismiss Notice
Dismiss Notice
This forum does not allow a single user to have more than one username. If anyone wants to change their username contact an admin and it will be done. Multiple accounts belonging to the same member will be deleted without warning.

Balun (Matching Network) for 5/8 Lambda

Discussion in 'Home Brew' started by bejo, Jan 4, 2010.

  1. bejo

    bejo member From Indonesia

    Joined:
    Jan 3, 2010
    Messages:
    40
    Likes Received:
    0
    Dear Senior member or all member, Iam From Indonesia (Malang - East Java)

    iam allready make 5/8 vertical antenna with radial 1/4 lambda (4 radial), iam working in 27.305.00 Mhz USB.
    Length antenna (5/8) = 6.52 meter
    Length Radial (1/4) = 2.61 meter



    iam used coil for loading 11 Turn with dia meter turn 1 1/4 " (cu wire 1.2 mm) and tap on 6 turn for matching,

    but iam can't get lower VSWR , now iam get VSWR 1:2.5 (near to red) iam allready change tap for matching but can't get lower VSWR

    any advise for me (new member) please help me...

    Thanks for your kind attention

    Sorry for my english
     

  2. Robb

    Robb Yup

    Joined:
    Dec 18, 2008
    Messages:
    11,404
    Likes Received:
    3,436
    English is OK!
    How high off of the ground is the antenna ?
    Large metal objects close by?

    http://www.worldwidedx.com/home-brew-mods/38300-64-homebrew-temporally-finished-up-pics.html
    Look at this 5/8 wave antenna; no matching coil.
    Uses aluminum loop to tune.
    Lower losses that a matching coil/balun would make.
    Notice that the ground plane radials are at an angle; this can also adjust the SWR.
    Might work with what you have built.
     
  3. bejo

    bejo member From Indonesia

    Joined:
    Jan 3, 2010
    Messages:
    40
    Likes Received:
    0
    Dear Rob KI6USW Rob KI6USW

    Thanks for your response,

    for high ground antenna is : 4 meter for ground (earth) but 2 meter from our top my house (Concrete).

    and for my radial is horizontal , we use all material allumunium except balun we use Copper wire 1.2 mm

    and for large metal i thing is no near large metal object

    we allready see .64 homebrew but not yet trial. for Uses aluminum loop to tune.

    is same length for inner 5/8 lambda (6.52 meter) ?

    and how about radial system, i want make by horizontal radial (4 radial) is no problem ? (i am allready have bracket for horisontal radial)

    Thanks for your kind attention
     
  4. Robb

    Robb Yup

    Joined:
    Dec 18, 2008
    Messages:
    11,404
    Likes Received:
    3,436
    http://www.worldwidedx.com/home-brew-mods/38300-64-homebrew-temporally-finished-up-pics.html

    This article shows a 5/8 lamda antenna.

    If you can angle your aluminum ground planes downward; it should lower your SWR!

    If you build an aluminum loop for your antenna; it will have better transmit and receive than a matching coil will.

    You can use most of the materials you already have.

    The vertical section that you have should be the same length, and the radial elements are the right length.
     
  5. bejo

    bejo member From Indonesia

    Joined:
    Jan 3, 2010
    Messages:
    40
    Likes Received:
    0
    Dear Mr Rob KI6USW

    ok i will try with alumunium loop , iam planing on week end to change the coil matchint to Alumunium loop.

    iam plan to use Tube alumunium 6 mm for alumunium loop is ok ?

    by the way you ask to me to change angle alumunium ground downward from horisontal,
    can you share or explain to us for different from Horisontal Ground with ground planes downward (example 45 degree) , is influence for transmit and Recieved ? or for local and DX Transmit and recieved ?

    Thanks for your kind attention
     
  6. Robb

    Robb Yup

    Joined:
    Dec 18, 2008
    Messages:
    11,404
    Likes Received:
    3,436
    The angle of the ground planes will affect the SWR when they are moved at a downward angle - yes..

    The article showed them at 45 degrees - not horizontal.

    Read the link I posted.
    Those pictures explain it all.
     
  7. bejo

    bejo member From Indonesia

    Joined:
    Jan 3, 2010
    Messages:
    40
    Likes Received:
    0
    ok sir...

    Thanks iam learning mode "On" now ian i will back to you soon
    with Picture my Antenna and result

    Thanks for your kind attention
     

Share This Page

  • About Us

    The WorldwideDX Radio Forum was originally established in 2001. We pride ourselves on welcoming Radio Hobby enthusiasts of all types, while offering unbiased, informative, and friendly discussion among the members. We are working every day to make sure our community is the best Radio Hobbyist's site.
  • Like us on Facebook

  • Premium VIP Member

    The management works very hard to make sure the community is running the best software, best designs, and all the other bells and whistles. Care to buy us a beer? We'd really appreciate it!

    Donate to us!