skyQ lnb no signal on one output

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OK, I guess " wizzy " was not the best choice of word. Just trying to get into my head how the omnipotent LNB works
Am I correct in my assumption that it is a " quattro " with only two outputs? And, can a standard stb decode this signal, or do you need a Q stb?
( Still wan´t to know about the test cable bit )
 
PaulR

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Again as I understand things, there are two outputs: one a full spectrum of the H and the other the V. I dare say a standard STB could be persuaded to decode some of the frequency range but it would have to be carefully instructed how to do it as the wholeband LNB doesn't respond to 13/18v or 22KHz switching.
 
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I take from what I read on the SS website they are using unicable LNB's with one cable and splitters, or are the splitters built in the Sky LNB?
Quote from the SS site....

The new Inverto Unicable SCR (Single Cable Router) LNB with splitters for 4 outputs. Connect up to 4 receivers
and only use 1 cable from the dish into the house. Please note that these LNBs only work if the satellite receiver
has a Unicable SCR option in it's menu. The latest Sky receivers do have this feature. The splitters come with the
LNB. All receivers work on all channels Just as if used with a quad LNB and 4 cables, but only one cable is needed.
The splitters are fitted indoors and are included. Three sets of 2-way splitters enables more flexibity than one
4-way splitter when sorting out the cable runs.
 
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I take from what I read on the SS website they are using unicable LNB's with one cable and splitters, or are the splitters built in the Sky LNB?
Quote from the SS site....

The new Inverto Unicable SCR (Single Cable Router) LNB with splitters for 4 outputs. Connect up to 4 receivers
and only use 1 cable from the dish into the house. Please note that these LNBs only work if the satellite receiver
has a Unicable SCR option in it's menu. The latest Sky receivers do have this feature. The splitters come with the
LNB. All receivers work on all channels Just as if used with a quad LNB and 4 cables, but only one cable is needed.
The splitters are fitted indoors and are included. Three sets of 2-way splitters enables more flexibity than one
4-way splitter when sorting out the cable runs.
Oh Bugger! I give up!
Unless the next question is about Live,Neutral and Earth, I don´t want to know.
Going back under my rock now, where its 25 degrees and has a decent water supply!
 
PaulR

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I take back the bit about two outputs as I didn't know the LNB was a unicable type. But it does make more sense.
 
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davemurgtroyd

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Additionally a distribution box is mentioned within the mix of new and legacy equipment conected on site. Quite how a dual band LNB can be used on a four port distribution box without a Q type expander to convert back to the four port requirement is anybody's guess based on the o/p's initial post. Was one installed before changing out the LNB on the roof ?
By the sound of it this is a distribution amplifier (not a multiswitch which I believe you are confusing it with) where two lnb inputs are input and one of them is multiplexed with the terrestrial signals and output and the other is merely straight through - such as this -- 8 Way Loft Distribution & Amplifier Unit Although there is no way that this sort of unit would work with Sky Q lnb (mixing terrestrial signal with overlapping frequency band from Sky Q lnb.
 
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The lowest frequencies are in what is currently terrestrial TV area and the highest frequencies are well above the high frequency of a standard LNB.
Nothing 'way above ' what can be brought into a normal system, which is why I mentioned the tuner in the first place. There is no change in the front end specification of the Q Sky box, everything is done with firmware.
 
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Given that I was wrong about the outputs and the LNB is a unicable type that's a moot point. But if I had been right then 2GHz of continuous frequency coverage would have to extend both below and above the "normal" IF range of a "normal" universal LNB
 
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yep I have a distribution box in the loft. BUT we totally bypassed that run ran a run of cable from the dish to the STB and it still failed! His test kit is connected to the LNB by a fly lead that was probably about 1.5m long, I asked him about it and he said its nothing fancy. I got him to connect around a 2m length of cable to the LNB and test at the end of that it FAILED!

Nice to see a good discussion about LNBs I did some sat comms stuff in my degree but that was wayyyyy back in the early 90's!
 
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I take back the bit about two outputs as I didn't know the LNB was a unicable type. But it does make more sense.
If it is a unicable why does it need two cables? I think not but I believe it is a two output wideband Sky Q lnb.
Given that I was wrong about the outputs and the LNB is a unicable type that's a moot point. But if I had been right then 2GHz of continuous frequency coverage would have to extend both below and above the "normal" IF range of a "normal" universal LNB
The standard Q lnb is NOT a unicable - it has two wideband outputs, one for each polarisation.
 
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Dunno Dave. I'm just going on what's been posted here. Are you saying that what I said to start off with is right?
 
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Dave's right, the standard Sky Q LNB has two outputs, both of which are needed for the Sky Q receiver, there is apparently a Hybrid LNB in the pipe, which will have two Sky Q outputs and four universal outputs.
 
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So,
Again as I understand things, there are two outputs: one a full spectrum of the H and the other the V. I dare say a standard STB could be persuaded to decode some of the frequency range but it would have to be carefully instructed how to do it as the wholeband LNB doesn't respond to 13/18v or 22KHz switching.
...was correct after all?
 
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So, ...was correct after all?
Looking at other forums two wideband outputs is correct, one V and one H. All band switching etc, must be done in the Q box. Perhaps Sky call it a Duocable LNB?
 
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All band switching etc, must be done in the Q box.
If the two outputs are wholeband of each polarity then the only switching will be from one input to the other. I suppose, theoretically, these two feeds could loop round the establishment and multiple Q devices could simply tap into the two cables in the same manner as original Ethernet over co-ax.

Lawd help me for suggesting that...
 
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Many of the " re-beam " companies here in Spain use either V or H polarisation thus enabling them to run multiple stb´s off a single lnb, normally using the " loop out " of the primary stb ( or secondary etc. etc. ) to provide the next stb as there is no contention between V or H, or high and low.
OK, granted that these LNBs use two cables to the stb, a loop for the entire house should be possible with two coax feeds. Only a matter of time before a " uni-cable " version is available, if it isn´t already.
All that conjecture does not solve the original problem though:(, why does it work on a test cable and not a short length of regular coax?
 
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Looking at other forums two wideband outputs is correct, one V and one H. All band switching etc, must be done in the Q box. Perhaps Sky call it a Duocable LNB?
No band switching required - the Sky Q has wideband tuners.
 
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right an update. Had another installer around yesterday, SkyQ expert, anyway exactly the same scenario! BUT we have a work around, moved the dish, its been moved about 15m to the other end of the house and everything now works! Still don't know what was causing the issue, but my money is on trees. Very Weird, and it was the V polarisation that was failing.
 
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