Help needed - why does Sky+ need two satellite inputs?

Simplified explanation: No, because the way the system works means a separate receiver is needed at the dish, which is done by having a dual LNB facing the dish. If you have two recording boxes, of course you need a quad LNB, with two feeds to each box. Unlike conventional TV, which can receive all frequencies at once, then extract the stations required, satellite only receives one station at a time. See, told you it was going to be simplified.

Quite correct Andrew. Also because of the way the signal beams are transmited from the sat itself, to cram in twice as many channels, they are split into horizontal and vertical polarizations. It is possible to split a single head into two different feeds, for two different tuners, but if one of the tuners tried to tune into a station on a different polarization than the one currently viewed, then that's when it wouldn't work! Merry Christmas from Norway!

That makes a lot of sense, thanks Andrew and Tonya. So, how many LNBs is it possible to have on one dish? If you wanted three Sky+ or Sky+HD boxes then is it possible to have a Dish with six LNBs or would you need to have two seperate dishes?

Also, this might sound like a really stupid thing to ask about, and I already kind of know the answer - well, sort of...  but I am interested in what someone more knowledgable than me would say...    How is it that Sky+HD can send a high-def signal from the dish to the set-top-box via a rubbish coaxial cable, but then the decoded signal has to be sent via at least component, or preferably HDMI - when originally it was sent perfectly well through coaxial?

Anyway, thankyou both very much...

Compression.

To answer your other question, you can get dual,quad and octo lnbs so a max of 8 feeds off one dish. I't's possible to have more feeds than that from a single dish but then your getting into the realms of a distrubution system which requires specialist equipment such as quattro lnb's, multiswitch's,distribution amps,taps and splitters etc........depending on how many feeds you require, and is the sort of thing used in communal systems for flat's etc...... so can be costly.

FWIW, a second dish isn't alway's an option, as depending on your local council may be against planning reg's to have more than one dish mounted on a building, unless you have the option to have something like a pole mounted/freestanding dish away from the building... e.g in the garden etc.

I have recently upgraded to Sky HD+ from standard sky. My new LNB that was installed has quad feeds. Obviously 2 are being used for my HD box.

Does what your saying mean that I can simply run a 3rd coax from a spare LNB feed to my old standard sky box in my bedroom and have free multiroom? (although it may be just the free to air channels)

 

yes you could run a third feed from your lnb and use your old standard sky box in that room.But as you said you would only get the free to air channels

you could also use the spare f-cable to hook-up a Humax Foxsat freesat box and get free-to-air BBC HD etc.

Is it a relatively easy job to connect a coax to the LNB, and would I need a sky freeview card?

Silentknight:

Is it a relatively easy job to connect a coax to the LNB, and would I need a sky freeview card?

Yes it's a relatively easy job to connect another feed to the lnb. Look for some good quality double screened 75 ohm cable such as ct100,pf100 or wf100,all basically the same cable but made by different manufacturers. You also a need a 'f' connector for each end of the cable,like this

If you need instructions on how to fit the 'F' connectors see this pdf.

Alternatively you can order ready made lengths from http://satellitesuperstore.co.uk/satellitecable.htm . At the lnb end of the cable either a rubber boot or amalgamating tape should be used to water proof the connection,again available from the above link.

As for needing a freeview card, You dont need a card for the likes of the bbc's, itv's and 4's and some of the music channels etc. You do need a card for the channel 5's and some of the music channels etc,

hope this helps

 

Helps a lot!!! Thanks, I'll get onto that job next...

Hi,

I was under the impression that Channel 4 requires a valid viewing card.

Could have changed obviously...

Cheers,

Cofnchtr.

Cofnchtr:

Hi, I was under the impression that Channel 4 requires a valid viewing card. Could have changed obviously... Cheers, Cofnchtr.

It did used to, but when they made e4 and more 4 available without subscription(as you didnt used to get those even with a freeview card) a while back, they all became available with-out a card

One more question, if I bought a secondhand Sky HD box would it be the sample principle to get the free channels including the HD ones. But just using 2 coax leads instead of the one?

 

yes and no.

Yes you could buy a second hand HD box and use that

No, you don't have to run two leads - one will do. Two connections are needed to enable you to watch one channel whilst recording another.