When the Foxsat-HDR finally goes tits up!

#1
When my Foxsat finally gives up (had it since day one) what's the best alternative. Not up with this tech anymore so would be interested to know what you guys would buy now.
 
#2
I would consider something like the VU+ Ultimo 4K and purchase a Unicable LNB, which in theory is 4K-ready and it would give you up to 16 simultaneously recordings (in theory):

http://vuplus.com/sub/sub0116.php

I have no experience with this box so I don't know how stable it is and how easy it is to configure and integrate with Freesat EPG.
 
#4
For my information: why does the LNB matter?
You can keep the LNB but will then have the same limitations in terms of concurrent recordings.

Going Unicable you can exploit the box's Full Band Capture (FBC), which should allow for up to 16 concurrent recordings.
 

Black Hole

May contain traces of nut
#5
Isn't that just a case of having a quad LNB and four feeds to the receiver (so both bands and both polarizations are covered)?
 
#6
Sure but the OP probably doesn't currently have more that 2 cables so it would be easier to go Unicable and have just 1 cable instead of 4.
 

Black Hole

May contain traces of nut
#7
Just done a bit of background reading (never hear of FBC before) and I can see that with a new design of LNB you can send the full frequency band to the tuner instead of only half, but I don't get how the polarisation issue is resolved into one cable feed.

(BTW: it's staggering that the broadband signal can be digitised and channels picked out by tuning in the digital domain!)
 
#8
Just done a bit of background reading (never hear of FBC before) and I can see that with a new design of LNB you can send the full frequency band to the tuner instead of only half, but I don't get how the polarisation issue is resolved into one cable feed.
Me neither but that's what some claim.
 

Black Hole

May contain traces of nut
#10
"Single cable distribution technology enables one coaxial cable from the antenna equipment to multiple tuners, to provide independent tuning across the whole range of satellite reception for each tuner."

I can't see anywhere in that article where it says how.
 

Black Hole

May contain traces of nut
#12
That explains nothing.

Regardless of splitters, if receiver A wants to access the horizontal set and receiver B wants to access the vertical set, how do you send both down the same wire? If a PVR wants to record programmes from the horizontal set and the vertical set simultaneously, how do you get the signals to it (down one wire)?

Conventional satellite TV systems use the LNB to down-shift the satellite transmission frequency band (microwave) to an intermediate frequency that is compatible with transmission through a coax cable. The microwave frequencies won't go down a cable. Conventionally the LNB is sent a command to select the upper or lower microwave frequency band and the horizontal or vertical polarisation.

Let's suppose we double the bandwidth of the IF, and can thus send the upper and lower microwave bands along the same cable (I don't know whether that is technically feasible, but if it is it will be a stretch). The only way to get the other polarisation down there simultaneously is to use another IF band - so the cable and electronics will have to have four times the bandwidth of a conventional system.

I'm not saying it can't be done, what I'm saying is I have seen no explanation how it is done (and I don't mean what you have to buy to make it work). It's the difference between "how does it work" and "how do you work it".
 
#13
That explains nothing.

Regardless of splitters, if receiver A wants to access the horizontal set and receiver B wants to access the vertical set, how do you send both down the same wire? If a PVR wants to record programmes from the horizontal set and the vertical set simultaneously, how do you get the signals to it (down one wire)?

Conventional satellite TV systems use the LNB to down-shift the satellite transmission frequency band (microwave) to an intermediate frequency that is compatible with transmission through a coax cable. The microwave frequencies won't go down a cable. Conventionally the LNB is sent a command to select the upper or lower microwave frequency band and the horizontal or vertical polarisation.

Let's suppose we double the bandwidth of the IF, and can thus send the upper and lower microwave bands along the same cable (I don't know whether that is technically feasible, but if it is it will be a stretch). The only way to get the other polarisation down there simultaneously is to use another IF band - so the cable and electronics will have to have four times the bandwidth of a conventional system.

I'm not saying it can't be done, what I'm saying is I have seen no explanation how it is done (and I don't mean what you have to buy to make it work). It's the difference between "how does it work" and "how do you work it".
You are describing the workings of a standard universal Ku band lnb.

Have you read the link. it seems pretty clear to me.

Special LNBs have been developed for use in single cable distribution systems. All four sub-bands of the Ku band (low frequency/horizontal polarity, high frequency/horizontal polarity, low frequency/vertical polarity, high frequency/vertical polarity) are received by a conventional front end, amplified and downconverted to the L-band, to be fed to a number of SatCR (Satellite Channel Router) – one for each user that can be connected - to further downconvert the required section of the received spectrum to centre on the user band IF frequency. The LNB further includes a combiner (i.e. reverse splitter) to merge the user bands together and a microcontroller to receive the instructions as to which frequency is required by each user and control the SatCR chips. [5]


https://www.microwaves101.com/encyclopedias/frequency-letter-bands

It's similar to the standard Q lnb that uses a lower IF allowing all horizontal frequencies to go on one cable and all vertical on a second, except it uses frequencies just above UHF to get all four combinations on a single cable with the tuner selecting which one is required. There is no band or polarisation switching on a Sky-Q receiver.
 
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Black Hole

May contain traces of nut
#14
I did read the link, but it didn't seem obvious (probably because I didn't realise a coax can have that wide a bandwidth). If somebody had said, at the start of this discussion, that all four microwave sub-bands get mapped onto separate IF bands, all would have been clear straight away.
 
#15
I did read the link, but it didn't seem obvious (probably because I didn't realise a coax can have that wide a bandwidth). If somebody had said, at the start of this discussion, that all four microwave sub-bands get mapped onto separate IF bands, all would have been clear straight away.
Why, a conventional aerial and it's downlead can handle the whole UHF band on a single cable ? It's just a question of choosing a IF within the cable capability.

Once you eliminate the band and polarisation switching it's much the same as terrestrial.

Sky-Q IF is within the UHF band so you cannot Multiplex Terrestrial TV and a Ku-Band universal lnb output onto a single cable.
 

prpr

Well-Known Member
#17
950-2150 MHz x4 is 4.8 GHz worth of bandwidth. Down a bit of cable? I don't think so. Something else must be going on.
Ah, reading the link quoted above it says "Please note that these LNBs only work if the satellite receiver has a Unicable SCR option in it's menu."
Apart from the aberrant apostrophe, it becomes pretty clear that you need a 'special' receiver which tells the LNB which frequency it wants, as well as high/low and polarisation selection.
Multiplexing n of these onto a cable is then a doddle compared to sending the full 1200 MHz.
Be nice to see one on a spectrum analyser.

Anyway, no use with a FoxSat, I'm sure, cos it don't have no Unicable SCR option it it's (sic) menu.
 

Black Hole

May contain traces of nut
#18
950-2150 MHz x4 is 4.8 GHz worth of bandwidth. Down a bit of cable? I don't think so. Something else must be going on.
That's what I think too, and why I was sceptical.
Apart from the aberrant apostrophe, it becomes pretty clear that you need a 'special' receiver which tells the LNB which frequency it wants, as well as high/low and polarisation selection.
What's the difference between that and what a conventional system does? I didn't read it that way; the way I read it is that the central distribution unit takes in the Unicable feed and recreates a conventional feed for each subscriber. For a communal system like that surely it's easier just to have four cables from the LNB (to cover all bases) and then switch these through to the distribution cables on demand.

The only way this Unicable thing makes sense is if they really can squeeze the full 4.8GHz band down the coax, but the digital tuner would then need to be able to sample the input at 10GHz!
 
#19
950-2150 MHz x4 is 4.8 GHz worth of bandwidth. Down a bit of cable? I don't think so. Something else must be going on.
Ah, reading the link quoted above it says "Please note that these LNBs only work if the satellite receiver has a Unicable SCR option in it's menu."
Apart from the aberrant apostrophe, it becomes pretty clear that you need a 'special' receiver which tells the LNB which frequency it wants, as well as high/low and polarisation selection.
Multiplexing n of these onto a cable is then a doddle compared to sending the full 1200 MHz.
Be nice to see one on a spectrum analyser.

Anyway, no use with a FoxSat, I'm sure, cos it don't have no Unicable SCR option it it's (sic) menu.
Wrong - The Foxsat-HDR is unicable capable. It's set up in the hidden menus. In fact way back Repassac (A My Humax) member set up a foxsat using a unicable lnb.

A 10 second Google search

http://www.satcure.co.uk/tech/unicab.htm
 
#20
Sky-Q doesn't split the Ku-Band and uses normal cables. LNB design is way superior to what they used to be. That's 6 GHz of bandwidth, they just seperate the horizontal and vertically polarised transponders, and lower the IF frequency used from that used for a universal lnb. You can use the same cable to deliver the whole VHF plus the whole UHF band, and a universal lnb feed.

https://www.amazon.co.uk/Quadplexed-Satellite-Aerial-Wall-Socket/dp/B003XN1TJ2

The above only has two cable inputs (Sat 2 is a seperate cable).
 
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