For well over 6 years I have been using an HB-1100S box. to decode the satellite signal. Although I live in France the reception from my satellite dish gives me full access to all the available UK channels. For obvious reasons I do not have access to Internet services such as ‘On Demand’. This box is connected to a Samsung smart TV. The satellite feed connects to my French digital terrestrial feed via a splitter and the common coaxial feed is split again in the room where the TV is located. The HB-1100S shows signal strength of close to 100% and quality of 100%. The digital terrestrial feed gives 100% for both. I have now installed a similar set up in another room in the house using a second newer Humax HB-1100S box attached to a newer but virtually identical Samsung smart TV. The setup for the feeds are identical to that used previously with the exception that the combined coaxial satellite/terrestrial digital feed is split now to provide 2 separate coaxial feeds to the different rooms. A splitter separates the signals, as before. The strength and quality of both the satellite and the digital terrestrial feeds received are identical in both rooms and remain at the same levels as when only one box was connected.
The problems occur when the boxes are tuned into different TV/radio channels. There are many different permutations of compatibility/incompatibility but for example if both are tuned to BBC1, the function is perfect with no change in signal strength/quality. However, changing one to ITV1 results in a complete loss of signal, usually to one box but very occasionally both. Turning the power off and then on, usually on one box but occasionally both restores function and full signal/quality as long as 'compatible channels are chosen.
I know very little about the technology involved but I seem to remember that the satellite transmissions are grouped together in different ‘band widths’. I am guessing that BBC1 and ITV1 are not in the same group. If that is correct, is the problem that I need a more ‘sophisticated’ head (LNB) for my dish to receive 2 different channels at the same time? I hope that is the solution rather than it is not possible to use 2 separate HB-1100S boxes attached the same satellite feed. All advice would be appreciated.
My Humax Forum » Freesat HD » HB 1000S, 1100S
Sharing input between two HB-1100S
(9 posts)-
| Sun 29 Nov 2020 13:54:32 #1 |
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You cannot split the outputs from a lnb.
Unlike a normal aerial. The tuner in the box not only powers the lnb it also has to control it.
Basically with this technology the whole of the frequencies used for satellite has to split the frequency band into two halves low or high and tell the lnb which band the the channel it needs is in. (it does this by adding a 22Khz tone to the the lnb to switch to high band). Only one tuner can have control. So the one not in control can only use channels in the same band and polarisation as the controlling tuner has switched the lnb to.
There is info here that identifies the band and polarisation used by Freesat channels.
https://myhumax.org/forum/topic/what-can-i-record-and-watch-using-1-or-2-cables
Adjacent transponders are opposite polarised horizontal/vertical. This allows more channels to fit in the available bandwidth.
The LB does this by changing the DC supply voltage.
A more comprehensive explanation is here.
You need a seperate cable back to the lnb for each tuner. You can get lnbs with 2 (rare in the), 4 or 8 outputs. So up to 8 tuners can be fed from a single lnb.
Most in the uk use a Sky type oval dish and a lnb designed to fit it because they are so cheap.
In France you are likely to have a offset dish that looks round from the lnb location. So you would need to source at least a twin (or larger) for your two single tuner boxes.
| Sun 29 Nov 2020 14:21:16 #2 | -
Hi Graham,
Thanks for responding and providing so much detail so quickly. I was somewhat depressed and panicked by your advice at first but that was mainly because the technicalities and some of the abbreviations you used were a bit over my head! When I realised that lnb = LNB and I assumed LB = tuner, calm returned! However, can I summarise your advice and what you suggest may be the possible route(s) out of my problem to be sure I really have got it!
1. I cannot run 2 boxes of any type from one LNB feed because the one which ‘locks on’ first will dictate which wave band the other will connect to.
2. Multiple output LNBs are available. I assume you made a typo “--- with 2 (rare in the UK)”. I guess it is important to confirm my assumption is correct, as a 2 LNB output would be optimal in my case. Is it difficult to find a supplier for 2 output LNB?
3. I would need a dish that is large enough to house a multiple output LNB. I am pretty sure you are correct that I have an offset dish but I will check this out with my installer. Initially we did have an oval ‘environmentally friendly’ dish but this did not work well. I am not sure of the exact size but it is on the ‘large size’. I will check this out with my installer. It may be that I should or will have to go for a second dish, each with its own single LNB. Do you agree? Installation/location of 2 would not be a problem.
4. You say that I would need a separate cable from each tuner to each LNB output. That would be possible but involve finding a route for an additional coaxial cable alongside the existing coaxial feed to the splitter in our basement, where it joins the coaxial lead from the terrestrial/digital antennae. This is sited close to the dish on our roof. Am I being naïve in wondering whether it would be possible to feed the 2 LNB outputs into the present single coaxial cable via an in/out splitter on the roof close to the dish/dishes and then split the input again at the other end where the conduits are already in place to provide the two tuners separately?
Thanks again for taking the time to answer my question so comprehensively. I hope that I have got it and look forward to your follow-up as soon as you have the time.
Alan| Sun 29 Nov 2020 17:37:23 #3 | -
Nalaselig - 2 mins ago »
Hi Graham,
Thanks for responding and providing so much detail so quickly. I was somewhat depressed and panicked by your advice at first but that was mainly because the technicalities and some of the abbreviations you used were a bit over my head! When I realised that lnb = LNB and I assumed LB = tuner, calm returned! However, can I summarise your advice and what you suggest may be the possible route(s) out of my problem to be sure I really have got it!| Sun 29 Nov 2020 17:48:35 #4 | -
grahamlthompson - 17 secs ago »
Nalaselig - 2 mins ago »
Hi Graham,
Thanks for responding and providing so much detail so quickly. I was somewhat depressed and panicked by your advice at first but that was mainly because the technicalities and some of the abbreviations you used were a bit over my head! When I realised that lnb = LNB and I assumed LB = tuner, calm returned! However, can I summarise your advice and what you suggest may be the possible route(s) out of my problem to be sure I really have got it!A 4 output lnb is like 4 seperate lnb's in one box. The only common component is the feedhorn with a waveguide behind it. This collects the microwave radiation the dish focusses on the feed horn. The lnb reduces the frequency so a normal coax can carry the signal.
You cannot fit splitters. Each tuner must have a seperate cable to one of the 4 outputs available on a 4 output one.
| Sun 29 Nov 2020 17:53:13 #5 | -
Hi Graham,
Thanks again. As I suspected I was being naive! Does your emphasis on a 4-output LNB imply that you think it will be difficult to acquire a 2-output version? Establishing a second dedicated coaxial cable to the 2nd output will be a bit expensive but certainly not difficult or impossible. Thanks to your help I will be able to discuss this with my installer in an informed way.
Regards
Alan| Sun 29 Nov 2020 18:43:36 #6 | -
Nalaselig - 19 mins ago »
Hi Graham,
Thanks again. As I suspected I was being naive! Does your emphasis on a 4-output LNB imply that you think it will be difficult to acquire a 2-output version? Establishing a second dedicated coaxial cable to the 2nd output will be a bit expensive but certainly not difficult or impossible. Thanks to your help I will be able to discuss this with my installer in an informed way.
Regards
AlanNo The difference in price is minimal. The major source of satellite in the UK is sky. They stopped using twin lnbs a long time ago until Sky-Q came along.
Don't lets get into sky-Q but it can deliver all channels using just two cables.
Before you get excited your Freesat box cannot use this lnb.
There are other ways but all of them mean you have to replace your two boxes.
Look at the UK price of a Sky-minidish with a quad lnb in the UK.
using a quad lnb means you could replace both your single tuner Freesat boxes with twin tuner Freesat+ pvrs.
| Sun 29 Nov 2020 19:11:36 #7 | -
Hi Graham,
Thanks! I think I have now got all the information I need to sort it out. I have pretty well decided to go with a second dish and running the second line to it doesn’t look to be a significant problem. I will discuss with my supplier whether to install a 2 or 4 output LNB. The flexibility of having 4 is interesting but at the moment replacing my present boxes is not a priority as I already have recording possibilities on both with external HDs. Assuming I can get both working independently if I want to record on one channel and watch on another, I can do this using the 2 boxes. However, if I install a 4 output LNB I will have that flexibility for future problems with my present boxes.
Thanks again. It has been a very productive interactive 24 hrs.
Alan| Mon 30 Nov 2020 6:25:51 #8 | -
Hi Graham,
I am afraid I have one more question about establishing a new feed for the new 4 – output LNB, that I will install either as a replacement for the LNB on my current dish or on an additional dish. The antenna for my terrestrial/digital feed is alongside my current dish on the roof. Could I use the use the terrestrial coaxial cable from the roof to the house to combine the inputs from the terrestrial antennae and the additional LNB output using a weather-proof coupler/splitter such as a Anttron C502 & then separate the signals at the other end using a Anttron C503? This would avoid the cost of establishing a completely new coaxial feed, which is also proving to be more difficult than I initially thought. I have attached Anttron spec sheets although I am sure you are familiar with them. My present system is already using an Anttron C502 to combine both the satellite & terrestrial into the single feeds for the individual rooms, where each is split again by an Anttron C503 to supply the TV & Freesatbox. As this works perfectly for both I am assuming it will also work as I am proposing. However, I may well be being naive yet again!
Regards
Alan| Mon 30 Nov 2020 13:30:44 #9 |
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