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6 Meter 5/8 gainmaster

Discussion in 'Amateur Radio Antennas' started by vkrules, Jun 27, 2015.

  1. vkrules

    vkrules
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  2. camaro1

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    made one for 6m last fall and hung it in a tree, works great
     
  3. vkrules

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    Looks like I will have to do a step by step construction now its on the front page.:D
     
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  4. tba02

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    I thank you for posting this, and if you do provide that step by step it might just be my next antenna project.
     
  5. vkrules

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    The 6m gainmaster is a center fed sleeved 5/8 dipole .
    The stub at the feed point is to match the antennas 200 ohm impedance to a usable 50 ohms . My prototypes swr was less than 1.3 from 50.100 to 53 mhz making it usfull for SSB operation as well as FM repeater work.
    Here is my step by step.Be patient might take me a while to get it posted.
    The cap, stub and tap are made from a single piece of RG213.(don't use RG58 for the stub at this frequency as the loss is to high) The bottom section including the choke is made from RG58.

    Start with a 1100 mm length of RG213 cable.
    Cut 30mm of sheath and braid off the top.Use a sharp knife and take care not to cut dielectric. IMG_1716.JPG
     
    #5 vkrules, Jul 11, 2015
    Last edited: Jul 11, 2015
  6. vkrules

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    Melt the dielectric over coax inner conductor.

    IMG_1717.JPG
     
    #6 vkrules, Jul 11, 2015
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  7. vkrules

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    Measure 43mm for the the cap and cut all the way around the cable through braid but not dielectric.


    IMG_1718.JPG
     
    #7 vkrules, Jul 11, 2015
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  8. vkrules

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    IMG_1719.JPG IMG_1720.JPG Slide cap up and measure 25mm gap. Solder wire for radiator. Seal with glue.
     
    #8 vkrules, Jul 11, 2015
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  9. vkrules

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    Measure down 700 mm from bottom of the gap for the Cap and preparing feed point tap. You can of course make this with connectors and a T piece.I choose not to because it doubles the cost of the project and isn't as streamlined.

    IMG_1721.JPG
     
    #9 vkrules, Jul 11, 2015
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  10. vkrules

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    IMG_1723.JPG And
    IMG_1724.JPG And
    IMG_1725.JPG
     
  11. vkrules

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    Notice i don't cut the cable all the way through
    IMG_1727.JPG
    Solder the tap
    IMG_1728.JPG
    To insulate the joint I used some scrap dielectric and put it through my hot melt glue gun. Did a nice job I think!!
    Remember the 30 mm off cut of braid at the start, slide it over the joint.
    IMG_1730.JPG
    Solder the ends and check for continuity make sure there is no shorts.Then seal it up. I used epoxy and over wrapped with electrical tape. I would normally use self amalgamating tape but I'm all out at the moment.
     
    #11 vkrules, Jul 13, 2015
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  12. vkrules

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    Next measure down the stub 310 mm add an extra 5 mm for a solder joint and solder the ends together. Note.Stub is shorted so you will see a short circuit at the coax end.
     
    #12 vkrules, Jul 13, 2015
    Last edited: Jul 13, 2015
  13. vkrules

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    Sorry for the delay been busy . Ok thats the stub waterproof after you solder the end
    station master 6m.jpg
     
  14. vkrules

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    Next measure down from the center ( bottom of the cap) 188cm and wind your 8 turn coil. On this one I used a plastic rattle can lid as the former , It just happened to be the right size ( 65 mm diameter).
    Note the tape on the rg-58 ,that was to mark the 188cm to wind the coil from .
    Hold in place with tape or zip tie ..
    stationmaster coil 6m.jpg
     
  15. vkrules

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    How you install it i will leave it up to you.
    You can put the radiator in pvc electrical conduit, fiberglass radome or hang it from a tree.
    Here it is going up on a 10 meter fishing pole.
    stationmaster goingup.jpg stationmaster goingup2.jpg stationmasterup.jpg
     

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