braychurchmouse
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Sorry this is a ridiculously long post but I've invested many hours of my life trying to fathom this out and hopefully it will help some folk with the same dilemma . Can I just say that I'm an absolute beginner on this and if there are any errors or inaccuracies in what I say, then I am very happy to be corrected.
I have been looking at a couple of threads recently http://www.avforums.com/forums/showthread.php?t=410987 and http://www.avforums.com/forums/showthread.php?t=679441 and wondering how to make a strategic decision on which digital system to adopt and what to consider in anticipation of a viable non-subscription satellite service (ie nonSky Freesat).
There doesnt seem anywhere to be a very clear explanation of techniques for distribution of satellite signals around the house, and how you go about providing facilities for different rooms to watch different programs. After all, that is the facility we get on analog with EACH tv in the house capable of receiving ANY programme. And with terrestrial digital Freeview you get that too if you have a separate Freeview receiver with each TV or recorder. (or built-in of course).
But what about satellite and in particular the so-called LOFT BOXES like the Labgear HDU681, HDU681S and similar? (the subject of one of the threads I mentioned above) ?
The first downer is that with the Loftbox "downlink-uplink" system used by a lot of these loftboxes just gives you an RF signal from your sat box to the rest of the house and, as this is a simple RF signal (NOT Nicam), the sound you get is MONO. Quite handy of course for the kitchen and kids bedroom but not exactly hifi sound to watch a film in the parents bedroom.
The second downer is that the system only supports ONE satellite receiver in the main room. OK, that receiver can be Sky Plus with input from two lnbs, but what you can't do is put another satellite receiver in the other rooms. Although the product description for many of these loft boxes implies exactly that by saying "distribute satellite signal to every room" ...what they actually mean is distribute a signal (RF) from the ONE satellite receiver you have in your main room. They do NOT distribute the LNB IF signal.
The Labgear documentation is one of the worst in that respect. I was about to buy a Labgear HDU681S after reading their product documentation, but was a bit curious when I noticed Satcure didn't stock it! (Anyway that's another story - do a search on the Satcure forum for comments about Labgear service, spares availability etc etc). The Labgear documentation is even more confusing about their unique switch to convert from satellite to non-satellite distribution. In the absence of any easily available documentation this appears to be just a switch to bypass the downlink-uplink loop. Quite useful I suppose, but then you'd probably make a link cable between the two anyway for testing purposes.
The third downer to the downlink/uplink approach is that your main UHF/RF signal around the house (ie your aerial UHF signal probably used for terrestrial Freeview) has to go into the loftbox, down the downlink to the main room, then back up again into the loftbox before it is distributed to the rest of the house. If you use the recommended triplexor and diplexor sockets your UHF signal goes through 9 plug/socket combinations before it finally gets to the TVs in the other rooms. (read what Satcure says about minimising plug/socket combinations to avoid interference and loss of signal.).
Ok, so why would you want a good UHF RF aerial signal in your other rooms when you have a satellite program availability? Well quite a few reasons - 1. You want decent high quality NICAM stereo sound or 2. You want to watch a different channel to what the folk in the lounge are watching . or 3. You have a Sky box in the main room with no subscription or Freesat-from-Sky card so you can't get Channel 5 or the History channel on satellite so you need terrestrial Freeview to watch those.. ...oh yes and you probably just paid good money for a brand new LCD telly with Freeview built in!
My temporary solution to distributing a Sky box signal is to forget about the downlink/uplink approach entirely. Tried a couple of Video sender solutions but not very satisfactory unless the sending and receiving rooms are pretty close. So we put in a three phono cable solution from the scart output at the back of the skybox giving us composite video and STEREO sound (left and right). Seems to work fine over 20 meters of cable. If you want to serve multiple rooms put in a video distribution amp (cheap one in Maplin handles stereo sound and video composite for £25), but you can get more expensive ones if quality and distance becomes an issue. We haven't had a problem. You can use the now redundant videosender to relay back the remote control signals to the Sky box. Or you could get a dedicated remote control transmitter like the Powermid. Or (and this is really cunning and I havent tried it...you could use a dedicated coax wire for the Skylink system plugged into the RF2 port on the Skybox!!!! - any comments).
Or you could go for the CAT5 wiring solution like Milestone, but a quick costing shows that even a simple system would cost £200 GBP or more.
So next stage is how do I distribute the LNB IF signal around the house to several independent Freesat (or even Sky) receivers?
OK there are good reasons why the LNB signal from ONE lnb can't easily be distributed to MANY satellite receivers. I guess the main one is that there is a need for voltage switching of the polarisation from horizontal to vertical, and the conflicts this would cause.
One partial solution is the next up on the cost ladder - a Loft Box which DOES distribute (in a limited way) lnb IF signals. One such is the Triax 333112 Loft box. From my reading of the specs this allows you to take in a two lnb feed for your Sky+ box in the main room (which can then be distributed to the rest of the house from the Sky box RF2 output in MONO sound as above using the downlink/uplink system). HOWEVER this Triax Loft Box ALSO has inputs for two additional lnb dish inputs which can be directed to two other rooms which have their own satellite receivers. Of course you can have other rooms in the house which can receive the satellite signal from the main receiver via the MONO RF2 outut. Indeed (oh boy this is confusing!) those two other privileged rooms with their own satellite receivers (stereo sound) can ALSO receive the satellite signal from the lounge via the RF2 output!!!!
This could be quite useful if your main box had a Sky subscription and/or was Sky plus so you could watch a paid movie or recorded program from that box in ANY room (but in MONO sound.) The two privileged rooms with their own satellite receivers would of course be able to watch any stations they were subscribed to in STEREO sound. The two privileged rooms have triplexed output wall plates for LNB, UHF (tv) and FM/DAB. The other rooms just have diplexed output plates for UHF and FM/DAB. In your main room though if you need the downlink/uplink facility you have Triplexed decombiner plate with 5 sockets.
I think this could be useful in a situation where you had a full Sky subscription for the lounge but had FreesatfromSky or later this year just Freesat receivers in the two other rooms.
You might say if the lnbs are dedicated to specific satellite receivers in specific rooms, why bother cabling them into the loftbox. My understanding of the Triax system is that it does mean that you only have to run one coax cable to each room instead of a separate UHF and LNB cable. Though running through the loft box and a wall plate would introduce 3 additional plug/socket connections, each reducing the signal potentially by 10% or so. A dedicated cable from the lnb though to the back of the receiver without a wall plate connection would be a better solution if the signal was weak. So why bother with the loftbox? except for UHF and FM/DAB distribution.
By the way this solution seems to require a dish/dishes with 4 completely independently switchable lnbs ie QUAD lnb which is the sort you can easily attach or replace on a Sky dish.
So lets now crank up the costs. The next stage up is a MULTISWITCH in its various forms.
see http://www.satcure.co.uk/accs/page1b.htm
These distribute multiple lnb inputs to multiple locations. It seems that most suppliers assume that these are facilities only required in blocks of flats or large hotels, but I believe that when Freesat comes along it will be a common requirement for many people. If people choose the Freesat option to go digital (as opposed to Terrestrial Freeview) there will be many homes with a typical requirement for at least 4 independently operating satellite receivers. Yes 4!!! Thats the main lounge, the kitchen, parents bedroom, kid1's bedroom, kid2's bedroom. Oh sorry that's 5. Will we all want to watch Holyoaks? or Match of the day? or Jamie Oliver.
My understanding is that Multiswitches require a QUATRO lnb (4 fixed outputs) and, THIS IS INTERESTING, this type of lnb apparently does not fit easily into a Sky dish, and you probably need one of the old style 60cm dishes. Glad you didnt throw away that old analog dish eh? (Oh you did?, well maybe do a bit of skip searching J.)
We dont of course yet know how much Freesat boxes will cost, but apart from the EPG circuitry they must be about as cheap to manufacture as current FreetoAir boxes (£50 from Maplin?) so we can presumably expect to see them bought in significant numbers for additional room use.
One consequence of all this is that if you are making a strategic decision to Go Satellite for your digital switchover, and you want the same sort of flexibility that you currently get with multiple TVs around the home that you get with analog or terrestrial Freeview, then maybe you should be thinking of swatting up on multiswitches and install an old 60cm or 80 cm style dish instead of a Skydish.
So enough of my rambling, I would welcome comments and a discussion of these issues, from the experts on this forum. I have found Davemurgatroyd2s comments extremely interesting and I think his skills will be very valuable in the coming months as nonSky Freesat gets nearer and is the option taken by many people in the digital switchover.
I have been looking at a couple of threads recently http://www.avforums.com/forums/showthread.php?t=410987 and http://www.avforums.com/forums/showthread.php?t=679441 and wondering how to make a strategic decision on which digital system to adopt and what to consider in anticipation of a viable non-subscription satellite service (ie nonSky Freesat).
There doesnt seem anywhere to be a very clear explanation of techniques for distribution of satellite signals around the house, and how you go about providing facilities for different rooms to watch different programs. After all, that is the facility we get on analog with EACH tv in the house capable of receiving ANY programme. And with terrestrial digital Freeview you get that too if you have a separate Freeview receiver with each TV or recorder. (or built-in of course).
But what about satellite and in particular the so-called LOFT BOXES like the Labgear HDU681, HDU681S and similar? (the subject of one of the threads I mentioned above) ?
The first downer is that with the Loftbox "downlink-uplink" system used by a lot of these loftboxes just gives you an RF signal from your sat box to the rest of the house and, as this is a simple RF signal (NOT Nicam), the sound you get is MONO. Quite handy of course for the kitchen and kids bedroom but not exactly hifi sound to watch a film in the parents bedroom.
The second downer is that the system only supports ONE satellite receiver in the main room. OK, that receiver can be Sky Plus with input from two lnbs, but what you can't do is put another satellite receiver in the other rooms. Although the product description for many of these loft boxes implies exactly that by saying "distribute satellite signal to every room" ...what they actually mean is distribute a signal (RF) from the ONE satellite receiver you have in your main room. They do NOT distribute the LNB IF signal.
The Labgear documentation is one of the worst in that respect. I was about to buy a Labgear HDU681S after reading their product documentation, but was a bit curious when I noticed Satcure didn't stock it! (Anyway that's another story - do a search on the Satcure forum for comments about Labgear service, spares availability etc etc). The Labgear documentation is even more confusing about their unique switch to convert from satellite to non-satellite distribution. In the absence of any easily available documentation this appears to be just a switch to bypass the downlink-uplink loop. Quite useful I suppose, but then you'd probably make a link cable between the two anyway for testing purposes.
The third downer to the downlink/uplink approach is that your main UHF/RF signal around the house (ie your aerial UHF signal probably used for terrestrial Freeview) has to go into the loftbox, down the downlink to the main room, then back up again into the loftbox before it is distributed to the rest of the house. If you use the recommended triplexor and diplexor sockets your UHF signal goes through 9 plug/socket combinations before it finally gets to the TVs in the other rooms. (read what Satcure says about minimising plug/socket combinations to avoid interference and loss of signal.).
Ok, so why would you want a good UHF RF aerial signal in your other rooms when you have a satellite program availability? Well quite a few reasons - 1. You want decent high quality NICAM stereo sound or 2. You want to watch a different channel to what the folk in the lounge are watching . or 3. You have a Sky box in the main room with no subscription or Freesat-from-Sky card so you can't get Channel 5 or the History channel on satellite so you need terrestrial Freeview to watch those.. ...oh yes and you probably just paid good money for a brand new LCD telly with Freeview built in!
My temporary solution to distributing a Sky box signal is to forget about the downlink/uplink approach entirely. Tried a couple of Video sender solutions but not very satisfactory unless the sending and receiving rooms are pretty close. So we put in a three phono cable solution from the scart output at the back of the skybox giving us composite video and STEREO sound (left and right). Seems to work fine over 20 meters of cable. If you want to serve multiple rooms put in a video distribution amp (cheap one in Maplin handles stereo sound and video composite for £25), but you can get more expensive ones if quality and distance becomes an issue. We haven't had a problem. You can use the now redundant videosender to relay back the remote control signals to the Sky box. Or you could get a dedicated remote control transmitter like the Powermid. Or (and this is really cunning and I havent tried it...you could use a dedicated coax wire for the Skylink system plugged into the RF2 port on the Skybox!!!! - any comments).
Or you could go for the CAT5 wiring solution like Milestone, but a quick costing shows that even a simple system would cost £200 GBP or more.
So next stage is how do I distribute the LNB IF signal around the house to several independent Freesat (or even Sky) receivers?
OK there are good reasons why the LNB signal from ONE lnb can't easily be distributed to MANY satellite receivers. I guess the main one is that there is a need for voltage switching of the polarisation from horizontal to vertical, and the conflicts this would cause.
One partial solution is the next up on the cost ladder - a Loft Box which DOES distribute (in a limited way) lnb IF signals. One such is the Triax 333112 Loft box. From my reading of the specs this allows you to take in a two lnb feed for your Sky+ box in the main room (which can then be distributed to the rest of the house from the Sky box RF2 output in MONO sound as above using the downlink/uplink system). HOWEVER this Triax Loft Box ALSO has inputs for two additional lnb dish inputs which can be directed to two other rooms which have their own satellite receivers. Of course you can have other rooms in the house which can receive the satellite signal from the main receiver via the MONO RF2 outut. Indeed (oh boy this is confusing!) those two other privileged rooms with their own satellite receivers (stereo sound) can ALSO receive the satellite signal from the lounge via the RF2 output!!!!
This could be quite useful if your main box had a Sky subscription and/or was Sky plus so you could watch a paid movie or recorded program from that box in ANY room (but in MONO sound.) The two privileged rooms with their own satellite receivers would of course be able to watch any stations they were subscribed to in STEREO sound. The two privileged rooms have triplexed output wall plates for LNB, UHF (tv) and FM/DAB. The other rooms just have diplexed output plates for UHF and FM/DAB. In your main room though if you need the downlink/uplink facility you have Triplexed decombiner plate with 5 sockets.
I think this could be useful in a situation where you had a full Sky subscription for the lounge but had FreesatfromSky or later this year just Freesat receivers in the two other rooms.
You might say if the lnbs are dedicated to specific satellite receivers in specific rooms, why bother cabling them into the loftbox. My understanding of the Triax system is that it does mean that you only have to run one coax cable to each room instead of a separate UHF and LNB cable. Though running through the loft box and a wall plate would introduce 3 additional plug/socket connections, each reducing the signal potentially by 10% or so. A dedicated cable from the lnb though to the back of the receiver without a wall plate connection would be a better solution if the signal was weak. So why bother with the loftbox? except for UHF and FM/DAB distribution.
By the way this solution seems to require a dish/dishes with 4 completely independently switchable lnbs ie QUAD lnb which is the sort you can easily attach or replace on a Sky dish.
So lets now crank up the costs. The next stage up is a MULTISWITCH in its various forms.
see http://www.satcure.co.uk/accs/page1b.htm
These distribute multiple lnb inputs to multiple locations. It seems that most suppliers assume that these are facilities only required in blocks of flats or large hotels, but I believe that when Freesat comes along it will be a common requirement for many people. If people choose the Freesat option to go digital (as opposed to Terrestrial Freeview) there will be many homes with a typical requirement for at least 4 independently operating satellite receivers. Yes 4!!! Thats the main lounge, the kitchen, parents bedroom, kid1's bedroom, kid2's bedroom. Oh sorry that's 5. Will we all want to watch Holyoaks? or Match of the day? or Jamie Oliver.
My understanding is that Multiswitches require a QUATRO lnb (4 fixed outputs) and, THIS IS INTERESTING, this type of lnb apparently does not fit easily into a Sky dish, and you probably need one of the old style 60cm dishes. Glad you didnt throw away that old analog dish eh? (Oh you did?, well maybe do a bit of skip searching J.)
We dont of course yet know how much Freesat boxes will cost, but apart from the EPG circuitry they must be about as cheap to manufacture as current FreetoAir boxes (£50 from Maplin?) so we can presumably expect to see them bought in significant numbers for additional room use.
One consequence of all this is that if you are making a strategic decision to Go Satellite for your digital switchover, and you want the same sort of flexibility that you currently get with multiple TVs around the home that you get with analog or terrestrial Freeview, then maybe you should be thinking of swatting up on multiswitches and install an old 60cm or 80 cm style dish instead of a Skydish.
So enough of my rambling, I would welcome comments and a discussion of these issues, from the experts on this forum. I have found Davemurgatroyd2s comments extremely interesting and I think his skills will be very valuable in the coming months as nonSky Freesat gets nearer and is the option taken by many people in the digital switchover.