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inexpensive antenna tuner for 10-12 meters on a sigma 4 ?

Discussion in 'CB and Export Equipment and Accessories' started by BOOTY MONSTER, Nov 1, 2011.

  1. what would be a decent AND inexpensive antenna tuner that will allow a sigma 4 to make a decent match for a 2950DX usable frequency range ? power would be about 200 pep .

    id also appreciate links to simplified/dummy down info on understanding tuners , how they work and what separates good ones from bad ones ..... if possible .

    thanks


     
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  2. Quiksilver

    Quiksilver Active Member

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    Possibly the LDG -200PRO / About $200-$250

    Products LDG Electronics
    [​IMG]
     
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  3. Robb

    Robb Yup

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    MFJ Enterprises Inc.

    One of these used can be had for ~$120

    How broadband is your Sigma IV?

    10m?????
     
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  4. hotrod

    hotrod Well-Known Member

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    try mfj 949
     
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  5. IMD262

    IMD262 Well-Known Member

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    If you plan on staying below 300W, look for a Dentron Jr. Monitor tuner.I've seen these at hamfests and swapmeets as lows as $20.The construction is 10X better than a comparable MFJ.

    [​IMG]

    [​IMG]
     
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  6. wavrider

    wavrider W9WDX Amateur Radio Club Member

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    #6
  7. Robb

    Robb Yup

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    Guts of the 949.

    There have been cases in which there is arcing in the variable capacitors.


    MFJ-949E Arcing! - YouTube
     

    Attached Files:

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  8. Wiskey Delta-40

    Wiskey Delta-40 W9WDX Amateur Radio Club Member

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    When i had my Sigma 4 up had it set for 27.000 and did the full 11 meter band no problem didnt go over 1.5 SWR on either end... didnt do high 28's so couldnt say... what it would do there



    and Booty you say you have a REAL Sigma 4 with the 3 arials that go to the hoop?
     
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  9. thanks guys . robb i dont know what the full usable tx range of the antenna is since i only have cb 40 here . i don't have a real sigma 4 , i have a homemade one with 4 basket elements like the vector 4k . and thanks for the suggestions . from what i understand these are not wide bandwidth antennas so i was thinking a tuner would be needed to cover the range of a rci 29xx or magnum 45/257 .

    im just trying to get a good idea of what it would cost me to get a little taste of the pork butt band . :eek:
     
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  10. Robb

    Robb Yup

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    I don't want to scare you off of the Ham butt band, but you will be a fair portion into it once you get a tuner.

    It will only be too easy for you to make your own 10-40m dipole for next to nothing. From there, a tech license will allow you to get what Hams call 'a real radio'. Which will have great filtering and adjacent freq rejection and cool, smooth RF output. It will spoil you.

    After you do that for awhile, you will want to do more than just listening on 40, 20, and 17m. You will want to talk there.

    And to think it all began when you bought your first ham tuner. You won't be the first, and maybe not the last. Besides, the idea of running 1,500 is as much a thrill as building your first hot rod too . . .
    (y):LOL:
     
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  11. BJ radionut

    BJ radionut Supporting Member

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    Booty: You might consider just "Bread Boarding"(building) your first tuner. They are really quite simple...The PI network is a good all around start...or the Simple "L" network works well and can be just what you need for minor adjustments using coax feed antennas. Granted not the most effective design,but simple to construct and easy to use.

    I have used about every basic design,
    T-Network/L-Network/Pi...etc...Presently a Link-Coupled(Johnson Matchbox) and a double "L"(homebrew) for two of my antennas feed with 450 Ohm Ladder Line.
    Just something to ponder, rather than purchase...your a good builder of "Thingies"(Sorry Doc)...so now your ready to take the next step...COOL..
    Let me know what you decide...I may have a few tips and component items here you could use...
    Looking forward to it future "Porker"(y)
    All the Best
    BJ
     
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  12. wavrider

    wavrider W9WDX Amateur Radio Club Member

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    AWWW Booty a future pork butter in the making:w00t:

    Nothing like having a morning cup of coffee, turn the rig on and find out how the weather is, In Asiatic Russia using 100 watts:eek:

    A lot of sites explain in detail and just how to build home brew tuners, but for SWL purposes you may not need a tuner to just "listen" in on the 10 and 12 meter bands.
     
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  13. n0zna

    n0zna W9WDX Amateur Radio Club Member

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    dentron or mfj dentron would be the best,i have a johnson viking but hard to find...73s de JW
     
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  14. W5LZ

    W5LZ Crotchety Old Bastard

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    The best 'simple' advice for a tuner for your antenna is that it should be rated to handle at least twice the power you think you might ever use. Why? Because of how tuners are typically 'rated' for power. As in bigger numbers makes you think it'd be more capable and manufacturers take advantage of that by using 'Pep' values. It's always a nice thing to have more capability than what you need. It all comes down to 'spacing'. The space between the turns of a coil and the space between the plates of a capacitor. The narrower/smaller those spaces the less voltage it takes to 'jump' or arc over. Any impedance transformation means higher than 'normal' voltages, so think 'bigger'.
    And then, the bigger those capacitors and coil are the 'wider' the range of impedances the thing will be able to handle. So the 'size' of a tuner can be a very, very rough gauge of what the thing can do. The bad part about arcing is that it always leaves traces, 'bad' spots that contribute to easier arcing the next time. Those 'bad spots' can be polished out, or fixed, but it's a lot of work.
    The warning that 'Robb' gave you is also something to think about cuz it's true! Once you get a taste of what's possible, it's kind'a hard not to want another taste...
    :)
    - 'Doc
     
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