1. In celebration of the launch of the new redesigned site, we just gave away a FREE antenna! Click Here to See Who Won!

poor mans gainmaster

Discussion in 'CB Antennas' started by bob85, Feb 13, 2012.

  1. bob85

    bob85 Supporting Member

    Joined:
    Mar 30, 2005
    Messages:
    2,175
    Likes Received:
    209
    me and a local decided to build a gainmaster from parts we have laying around the shack, if it works as intended we will build a higher power version.
    [​IMG]
    [​IMG]


     
    #1
  2. rabbiporkchop

    rabbiporkchop Active Member

    Joined:
    Jan 18, 2007
    Messages:
    136
    Likes Received:
    4
    #2
  3. Mudfoot

    Mudfoot Supporting Member

    Joined:
    Jun 17, 2009
    Messages:
    7,543
    Likes Received:
    2,215
    Sirio will unleash their attorneys on ya'll.
     
    #3
  4. Needle Bender

    Needle Bender Well-Known Member

    Joined:
    May 15, 2010
    Messages:
    927
    Likes Received:
    104
    You probably meant that tongue in cheek, so not for personal use.
    The patent is for marketing an identical product.
    Bob what's the impedance of the red coax?
     
    #4
  5. HomerBB

    HomerBB Well-Known Member

    Joined:
    Jan 4, 2009
    Messages:
    2,496
    Likes Received:
    404
    Will be watching this, Bob.
     
    #5
  6. binrat

    binrat W9WDX Amateur Radio Club Member

    Joined:
    Nov 5, 2008
    Messages:
    1,242
    Likes Received:
    241
    I think a few people including me will be looking forward to udates.
     
    #6
  7. Needle Bender

    Needle Bender Well-Known Member

    Joined:
    May 15, 2010
    Messages:
    927
    Likes Received:
    104
    The Gainmaster is a $179 vertically polarized, balanced, center fed, wide bandwidth, 5/8 antenna made from coax and wire, housed within a telescoping fiberglass radome, with about 66% more 'in-phase' active element area than a normal bottom fed 3-4 radial metal 5/8, and which provides about 1-2db more gain on the horizon than the $150 Super Penetrator 500 or the $359 I10k.

    Go here and click on the links on top in the orange area to read all about it. I love mine!

    My Penetrator 500 is now a pile of disassembled aluminum tubing and parts stored in the garage as a back up antenna.
     
    #7
  8. nice project bob , be sure to post plenty of pics for us (y)
    what are you gonna use for the support tubing ? i recall reading somewhere that the velocity factor of that tubing effects the antenna inside quite a bit .
     
    #8
  9. Robb

    Robb Yup

    Joined:
    Dec 18, 2008
    Messages:
    8,208
    Likes Received:
    1,015
    Yes; lotsa pictures please . . .
     
    #9
  10. bob85

    bob85 Supporting Member

    Joined:
    Mar 30, 2005
    Messages:
    2,175
    Likes Received:
    209
    needlebender
    the red stuff is the wire for the upper half, we will try different coax and see how it goes,

    booty
    we will be using fiberglass fishing poles as support, the dielectric properties of the radome will effect the antenna to some extent,
    its just an experiment using things laying around.
     
    #10
  11. Needle Bender

    Needle Bender Well-Known Member

    Joined:
    May 15, 2010
    Messages:
    927
    Likes Received:
    104
    Any idea of the impedance or capacitance per foot of the factory Gainmaster Red coax?
    Your red coax isn't the same?
     
    #11
  12. bob85

    bob85 Supporting Member

    Joined:
    Mar 30, 2005
    Messages:
    2,175
    Likes Received:
    209
    we don't know what the red coax is, its 5mm same as rg58, you have standing waves on the section of coax above the stub, 500w into rg58 with high vswr is pushing it hard.
     
    #12
  13. Robb

    Robb Yup

    Joined:
    Dec 18, 2008
    Messages:
    8,208
    Likes Received:
    1,015
    If I remember correctly, there is supposed to be a tuning stub in there too.
    Interested in how this all looks before you plop it all into the radome.
     
    #13
  14. Marconi

    Marconi Supporting Member

    Joined:
    Oct 23, 2005
    Messages:
    4,254
    Likes Received:
    293
    Hey Bob, quite the enterprising idea there.

    Over here I would think the base element alone, 1 - 3/4" x 75" fg fishing pole, would cost quite a bit, and you'll still need three more smaller sizes too. Why not consider to hang the prototype between two trees and work out the kinks, unless you think adding back the support material will be a big contributing factor for the tuning. Here is a link that might be helpful: Installing Wire Antennas

    Whatever happened to your project to build a New Top One out of a Vector? I saw a picture of one you made that looked very similar. A neighbor of yours from Ireland just posted about his success with his New Top One.

    Keep us posted.
     
    #14
  15. Mudfoot

    Mudfoot Supporting Member

    Joined:
    Jun 17, 2009
    Messages:
    7,543
    Likes Received:
    2,215
    Can you guestimate production cost of materials when done?
     
    #15

Share This Page