Hybrid LNB

Discussion in 'Satellite TV, Sky TV & FreeSat' started by winston2010, Dec 3, 2017.

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  1. winston2010

    winston2010
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    I've asked this elsewhere but got no response so:

    Does anyone know how a hybrid LNB can detect whether a Q box or normal box is connected? I assume it defaults to normal mode unless a Q box is connected. If so this must mean the Q box must send some sort of signal. Anyone know?
     
  2. davemurgatroyd2

    davemurgatroyd2
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    Could it be down to voltage on cable
     
  3. winston2010

    winston2010
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    Maybe, but does a Q box use different LNB voltages? It could also be some sort of tone signalling but does anyone actually know how it works?
     
  4. grahamlthompson

    grahamlthompson
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    A Sky-Q box outputs 12V (it's in the box spec). A standard universal normally has a minimum output of 12.5V when using vertical polarisation and 15.5 when switched to horizontal. Whether the 0.5V is enough to tell not sure. I would have thought a long coax run would confuse the lnb.

    There's no band or polarisation switching on a Sky-Q lnb. The IF used is lower and allows all Low Band and High Band vertically polarised transponders to be carried on one cable, and all the horizontal on the other.

    A standard universal only has a tone when it needs to access high band transponders.

    A standard Sky-Q lnb only has two outputs.
     
  5. winston2010

    winston2010
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    That is all straight forward. Obviously a Q LNB has dedicated H and V outputs and a Q box has dedicated inputs. Can see some confusion with getting the cables the wrong way round but assume installers would notice if it was wrong.

    Back to a hybrid LNB. I understand any 2 outputs can be used with Q. Are some outputs dedicated H and some V? If not how does the LNB know? I don't think 12v as against 12.5v is enough to differentiate with a standard receiver. I wonder if it is possible to use 2 Q receivers on 4 outputs (not that that would be necessary as with no voltage/tone switching simple passive splitters can be used).
    There seems to be no information at all on any of this.
     
  6. Fred Smith

    Fred Smith
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    The outputs of the LNB do not appear to be dedicated, I assume the Q box inputs are.
     
  7. winston2010

    winston2010
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    OK, so how does the hybrid LNB know which output to send V and which out to send H to a Q box and how does it know a Q box is connected rather than a standard box?
     
  8. Fred Smith

    Fred Smith
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    You can connect a Q box to any of the six outputs so it must be the box inputs that are dedicated to H & V.
     
    Last edited: Dec 4, 2017
  9. TJT1

    TJT1
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    But that still does not address the OP's question.
     
  10. Fred Smith

    Fred Smith
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    Well if you know better....
     
  11. TJT1

    TJT1
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    No, I don't, :(but at least I understood the question, and am interested in the real answer as it seems a bit puzzling how it's done:D
     
  12. Fred Smith

    Fred Smith
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    I understood it also, I answered what I though was possibly correct and did not answer what I don't know.

    I'm sure the OP could find the answers using a search engine. After all it just Sky's propriety version of the technology.
     
  13. grahamlthompson

    grahamlthompson
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  14. Antsue

    Antsue
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    Sorry as I'm 71 and not that up on tech can someone tell me in plain info why the q box works and the sky plus hd box works both from the hybrid lnb.As the sky plus hd box must be useing the same signal as the standard lnb but the Bush box can't see anything yet it's advertised that if you have an ordinary sky box i.e. hd you can just swap them round as that is what I did i.e. Bush for hd box but got no results
     
  15. Fred Smith

    Fred Smith
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    What Bush box?

    I use a LG OLED TV and Ferguson HD satellite box both work fine on the hybrid lnb, as do occasionally a Goodmans, Humax and Openbox satellite receivers, all with currently with a Sky Q also connected.
     
  16. Antsue

    Antsue
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    Bush hd 500gb
     
  17. Fred Smith

    Fred Smith
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    You need to be specific that could be a Freeview receiver!
     
  18. winston2010

    winston2010
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    Indeed. But as I said in your other post:

    "Perhaps the hybrid LNB does not recognise your Freesat box for what it is. No one seems to know how a hybrid LNB determines what is connected to it."

    Until we find out how a hybrid LNB knows what type of box is connected to it, it will remain a mistory.
     
  19. Antsue

    Antsue
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    Bush 500GB FREESAT+HD DIGITAL TV RECORDER BUT I THINK I MIGHT SEND THIS BACK AND TRY A HUMAX 1100s
     
  20. JayCee

    JayCee
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    That's it's description.
    The model number will be printed on a label probably on the bottom or rear of the box.
     
  21. Antsue

    Antsue
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    Sorry about that I've sent it back this, morning will try something else silly really all because sky won't let you run its plus box beside the q box only as a locked free sat and the wife uses it around the house to watch her soaps in different rooms as she dose what ever it is wives find to do
     

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