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  1. #1
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    Default Prime & Offset Ku Lnb ??


    I have known Lnbs Ku and C band,
    Now I have come across prime focus
    and offset KU lnb.

    Whats the real difference as in
    functions, mountings etc?
    where i have come across it one tends to
    be more expensive that the other, and no
    photo references.

  2. #2
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    Default

    Quote Originally Posted by cogil View Post
    I have known Lnbs Ku and C band,
    Now I have come across prime focus
    and offset KU lnb.

    Whats the real difference as in
    functions, mountings etc?
    where i have come across it one tends to
    be more expensive that the other, and no
    photo references.

    I only use prime focus dishes as I prefer them especially as I have to brace them for typhoons. Offsets have one arm holding the lnb below the dish whereas prime focus has 3. I also prefer this as the arms can get hit by flying debris in high winds. Offsets look smaller but a 1.8m offset should give the same gain as prime focus.

    Apart from that nothing to choose from excpet I have not seen a mesh offset dish only solids.
    If Evolution works, why so many idiots?


  3. #3
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    Default

    Quote Originally Posted by ******2engineer View Post
    ............ excpet I have not seen a mesh offset dish only solids.
    But have you seen an Eliptical 60cm Mesh Dish? my bro-in-laws got 1 like this. can you notice that it is similar to an offset dish only it is positioned sideways making it eliptical.

    No GUTS!No GLORY!
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  4. #4
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    Default

    Quote Originally Posted by cogil View Post
    I have known Lnbs Ku and C band,
    Now I have come across prime focus
    and offset KU lnb.

    Whats the real difference as in
    functions, mountings etc?
    where i have come across it one tends to
    be more expensive that the other, and no
    photo references.
    Refer to Mark long's website:

    http://www.mlesat.com/Article1.html

  5. #5
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    Default

    thanks for the replies, but what i have a pick with is
    LNB Ku being prime and offset,
    i still do need more just to make me pick the meaning.

  6. #6
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    Default

    i think, the advantage generally goes to the circular dish/Prime focus lnb, that if you're processing signals from one satellite only. eliptical or even offset dish with offset lnb's are typically employed in multi-sat configurations.

    basically means that the eliptical/offset dishes in the UK for the lower end consumer services will not be suitable scenario in southern Africa. At 45dB it would probably be sensible to get a 1.2m circular parabola.
    i'm talking on cheap stuff. if you are in not going to have a multi-sat config. then go for prime focus dish with prime focus lnb.
    No GUTS!No GLORY!
    .

  7. #7
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    Default

    The Ku LNB is exactly the same, the differance between the Off-set model and the prime focus model, is the feed Horn is cut on a taper for the OFF-set , and flat, simler to a C-band type but smaller.

    many off-set Ku LNB's have the feedhorn, and the LNB body in the one casting, and the feed horn os not removeable, it depends on the manifacturer. Brands like MTI, have both designs, be they standard or Universial. MTI are aslso one of the few manifacturers to produce a Universial Ku prime focus LNB.
    regards from OZ bassett

  8. #8
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    Default

    Quote Originally Posted by bassett View Post
    MTI are aslso one of the few manifacturers to produce a Universial Ku prime focus LNB.
    I wont use the MTI as the Fuji has 15% more gain than an MTI.
    If Evolution works, why so many idiots?


  9. #9
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    Default

    @Cogil,
    As mentioned by Basset here is a picture of a Ku band lnb with a mini feedhorn attached to its body.
    The speciality of such lnb in my personal experience is that very low signals remain constant & do not fluctuate. This lnb is mounted on a solid prime focus dish.


  10. #10
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    Default


    @ basett and dom,
    you are giving me the idea
    that it is dependent on the,feedhorn,
    which i think is correct, for that reason I have never seen a
    prime focus ku lnb, all i have seen is offset, take it as joke
    but thats the truth.
    whenever I use an Ku-Lnb on prime focus dish, there has to be
    an adaptor to fit it on the scaler ring - imagine.

 

 

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