The Lemon Fool

jfgw wrote:If the previous owner had a SkyQ box, however, you would need to replace the LNB with a conventional one.

What is the basic difference between a SkyQ LNB and a "conventional" one? The Intermediate frequency maybe? C.

csearle wrote:

jfgw wrote:If the previous owner had a SkyQ box, however, you would need to replace the LNB with a conventional one.

What is the basic difference between a SkyQ LNB and a "conventional" one? The Intermediate frequency maybe? C.

Sky Q uses a wideband LNB. There's no switching between the top and bottom end (using a 22kHz signal from receiver to LNB).
ISTR that the two feeds are used to allow recording from transponders with different polarisation, rather than from transponders which are on different polarisation and/or in different halves of the Ku-band.

pochisoldi wrote:

csearle wrote:What is the basic difference between a SkyQ LNB and a "conventional" one? The Intermediate frequency maybe? C.

Sky Q uses a wideband LNB. There's no switching between the top and bottom end (using a 22kHz signal from receiver to LNB).
ISTR that the two feeds are used to allow recording from transponders with different polarisation, rather than from transponders which are on different polarisation and/or in different halves of the Ku-band.

I thought that the reason for two leads was so that you could record one channel while viewing another. You have 2 LNBs at the dish.

TJH

tjh290633 wrote:

pochisoldi wrote:
Sky Q uses a wideband LNB. There's no switching between the top and bottom end (using a 22kHz signal from receiver to LNB).
ISTR that the two feeds are used to allow recording from transponders with different polarisation, rather than from transponders which are on different polarisation and/or in different halves of the Ku-band.

I thought that the reason for two leads was so that you could record one channel while viewing another. You have 2 LNBs at the dish.

TJH

The old way you could record/watch 2 channels (limited by number of LNB feeds). The box had two tuners each tied to an LNB feed.
The Sky Q way means you are limited by the number of tuners in the receiver.

Or put another way, it makes satellite telly more like terrestrial - one aerial feeds multiple tuners (TV's pvrs etc), but with satellite you need two "aerials" - one for each kind of polarization to give full "coverage."

The microwave signals picked up by a dish don't travel down coaxial cable very well so they are converted to lower frequencies by the LNB. The LNB needs power but this is fed up the coax from the sky box or other receiver. With a conventional LNB, 13V selects vertical polarisation and 18V selects horizontal polarisation. In addition, a 22kHz tone is used to select the upper half of the band. If the tone is absent, the lower half is selected. Thus, each cable only carries 1/4 of the total available channels at any time. Two feeds to a suitable sky box allow you to watch one channel and record any other simultaneously. Additional receivers usually have their own connection to the LNB. LNBs with 8 outputs are readily available.

SkyQ LNBs are wide-band. There are two cables, one for horizontal polarisation and one for vertical polarisation, but each cable carries the full range of frequencies. The LNBs have only 2 outlets.


Julian F. G. W.

Redmires wrote:Same here. We use an old Sky dish for Freesat TV. The area is not great for normal TV and the dish provides far better reception than the TV aerial.

This exactly what we would like to do. There's a Sky dish installed by previous owners and the cables from the dish are conveniently located near where we have the TV. There are two cables from the dish, however, and please could you tell me if both of these need to be connected for FreeSat to work? To test if the dish is working, I'm thinking I'll buy a secondhand FreeSat box off ebay and test it. The box I'm considering has a socket for only one of the cables, would that be a problem? My TV is modern enough to work with internet (via Amazon Firestick) no has no inbuilt FreeSat.

bruncher wrote:

Redmires wrote:Same here. We use an old Sky dish for Freesat TV. The area is not great for normal TV and the dish provides far better reception than the TV aerial.

This exactly what we would like to do. There's a Sky dish installed by previous owners and the cables from the dish are conveniently located near where we have the TV. There are two cables from the dish, however, and please could you tell me if both of these need to be connected for FreeSat to work? To test if the dish is working, I'm thinking I'll buy a secondhand FreeSat box off ebay and test it. The box I'm considering has a socket for only one of the cables, would that be a problem? My TV is modern enough to work with internet (via Amazon Firestick) no has no inbuilt FreeSat.

If you look at the comments above, the Sky HD box has two inputs to allow it to record one channel while you watch another. If your Freesat box has just one input that just needs one cable from the dish.

TJH

tjh290633 wrote:

bruncher wrote:
This exactly what we would like to do. There's a Sky dish installed by previous owners and the cables from the dish are conveniently located near where we have the TV. There are two cables from the dish, however, and please could you tell me if both of these need to be connected for FreeSat to work? To test if the dish is working, I'm thinking I'll buy a secondhand FreeSat box off ebay and test it. The box I'm considering has a socket for only one of the cables, would that be a problem? My TV is modern enough to work with internet (via Amazon Firestick) no has no inbuilt FreeSat.

If you look at the comments above, the Sky HD box has two inputs to allow it to record one channel while you watch another. If your Freesat box has just one input that just needs one cable from the dish.

TJH

Yes, the same with our Humax freesat which has two. The two inputs mean you can record two channels at the same time. If you want this facility you need to buy a freesat box with two inputs. If not, then a one input box will do the job.

Thanks. Interesting that Humax have discontinued all Freesat boxes. I guess new TV's have the tech built in, the same thing happened with Freeview.