Channel 4HD

excollier

This is coming to Freesat in April.:D:D:D
http://www.joinfreesat.co.uk/

Sky will start to look (even more) expensive soon.
That will be four HD channels, FREE!! Gratis! No sub! No recording charge!!:D
Surely more to follow.

Sorry!! I missed the earlier thread:o

Good news though all the same...

The Cush

Info posted yesterday morning - http://www.boards.ie/vbulletin/showthread.php?t=2056166993

NIMAN

Thats good news, although I'd still call it 3 channels rather than 4, as splitting the BBC ones into BBC1 HD and BBC HD is stretching things a bit.;)

excollier

NIMAN wrote: »

Thats good news, although I'd still call it 3 channels rather than 4, as splitting the BBC ones into BBC1 HD and BBC HD is stretching things a bit.;)

OK-but still, it's free, unlike Sky, and more will probably follow.

Johnmb

NIMAN wrote: »

Thats good news, although I'd still call it 3 channels rather than 4, as splitting the BBC ones into BBC1 HD and BBC HD is stretching things a bit.;)

In fairness, they are two completely different channels. BBC1 HD is a simulcast of the main channel, and BBC HD show a simulcast of a selection of BBC2, 3, and 4 shows, along with some programs that aren't on any of them.

BArra

i would assume C4HD will be available to sky customers through other channels

lgs 4

BArra wrote: »

i would assume C4HD will be available to sky customers through other channels

sky boxs dont have the symbol rating 29500 thats if channel 4 hd stay where they are on 11798 ,29500 ,3/4 :rolleyes:

enfant terrible

What's the cheapest Freesat HD recorder box?

lgs 4

enfant terrible wrote: »

What's the cheapest Freesat HD recorder box?

i dont know about cheapest freesat hd boxs i have humax pvr hd no problems and i also use it with astra 1 19e and hot bird 13e on the nonfreesat mode a good all round hd box

Minstrel27

NIMAN wrote: »

Thats good news, although I'd still call it 3 channels rather than 4, as splitting the BBC ones into BBC1 HD and BBC HD is stretching things a bit.;)

BBC One HD and BBC HD have two completely different schedules. Why would it be stretching things?

evilivor

NIMAN wrote: »

Thats good news, although I'd still call it 3 channels rather than 4, as splitting the BBC ones into BBC1 HD and BBC HD is stretching things a bit.;)

Totally different channels.

Pat Gleeson

lgs 4 wrote: »

sky boxs dont have the symbol rating 29500 thats if channel 4 hd stay where they are on 11798 ,29500 ,3/4 :rolleyes:

Because Sky's boxes are restricted to two symbol rates 22.0 and 27.5, to go FTA, C4 will use one of these. All FTA channels have to be viewable on different boxes. If they stay on the same frequency it would be 27.5, but they will probably move to where the other Freesat / FTA channels are.

Rick_

Channel 4 HD will be on the same transponder as BBC HD and BBC ONE HD so it will be using the same symbol rate and FEC, so Irish Sky+HD receivers will be able to tune it in.

Apogee

Paddy C wrote: »

Channel 4 HD will be on the same transponder as BBC HD and BBC ONE HD so it will be using the same symbol rate and FEC, so Irish Sky+HD receivers will be able to tune it in.

If C4HD moves to the same TP, then presumably it will entail a change to DVB-S2 in order to accommodate 3 HD channels?

NIMAN

ok I accept it, there's now 4 HD channels:o

Hopefully more to follow.

Rick_

Apogee wrote: »

If C4HD moves to the same TP, then presumably it will entail a change to DVB-S2 in order to accommodate 3 HD channels?

No need, there is enough space on the transponder to house 3 HD channels as it is, and if the transponder had to switch to S2, that would require a clearout of channels for possibly a fortnight for testing, which means no BBC HD and no BBC ONE HD which would not go down very well with the public, not to mention the DVB satellite cards people have that would be rendered useless.

Apogee

Paddy C wrote: »

No need, there is enough space on the transponder to house 3 HD channels as it is,

I was trying to figure where sufficent space would come from if the existing BBC HD channels were transmitting at 12-15Mbps as when BBCHD started initially. So I went and checked but I hadn't realised the reduction in bitrates was so dramatic - down to 5-7/8Mbps. So certainly sufficient space at those rates.

Paddy C wrote: »

and if the transponder had to switch to S2, that would require a clearout of channels for possibly a fortnight for testing, which means no BBC HD and no BBC ONE HD which would not go down very well with the public, not to mention the DVB satellite cards people have that would be rendered useless.

The long term benefits of an additional 10Mbps (from ~33Mbps to ~44Mbps per TP) by moving to DVB-S2 would outweigh any inconveniences during switchover imo, esp given that space on Astra 2D is at a premium. Since they have already cleared out the SD channels from that TP, the next logical step would be a change to DVB-S2.

I'm sure they could come up with an interim transmission plan which would not see BBC HD and BBC One HD showing blank screens for a fortnight. And that they would stick with DVB-S for the sake of a few DVB-S PCI card owners seems fanciful TBH.

Rick_

Well, I doubt the people using satellite cards which are DVB-S are of any concern to them, but finding alternative space to house their 2 HD channels whilst the transponder is switched to S2 would be interesting as well, there isn't any, not on 2D anyway and I doubt Sky are going to give them a helping hand.

The change to 2D mightn't actually create any extra space as such, but more change the options available for transmissions making the bandwidth better used. I seem to recall reading somewhere that it wasn't possible to convert 2D transponders to S2 due to age or something, but I'm not 100% sure on that. Anyway, with 1N and 3E launching This year and next, plenty more space will be available on Astra 2 before long and every broadcaster can have their own transponders to launch all their channels in HD and FTA safely without having to worry about rights issues. It's just gonna take time.

Apogee

Paddy C wrote: »

Well, I doubt the people using satellite cards which are DVB-S are of any concern to them, but finding alternative space to house their 2 HD channels whilst the transponder is switched to S2 would be interesting as well, there isn't any, not on 2D anyway and I doubt Sky are going to give them a helping hand.

I'm not sure it's that particularly complicated or would take as long as a fortnight. I don't see why they couldn't do initial tests in the early hours of the morning over a few weeks on DVB-S2, and then switching permanently all going well?

Paddy C wrote: »

The change to 2D mightn't actually create any extra space as such, but more change the options available for transmissions making the bandwidth better used.

DVB-S2 is inherently more efficient than DVB-S so there would be an immediate bang for your buck in terms of overall data transmission capacity. There is a very nice article in New Scientist on the coding/modulation/efficiencies - unfortunately subs required - but I might have the original knocking about if I can find it.

http://www.newscientist.com/article/mg18725071.400
http://www.dvb.org/documents//DVB-S2%20Presentation.pdf

Paddy C wrote: »

I seem to recall reading somewhere that it wasn't possible to convert 2D transponders to S2 due to age or something, but I'm not 100% sure on that.

No, that doesn't make sense. The transponders are just (amplified) pipes in space and don't "care" what the modulation of the signal is.

[edit] PDF of article attached.

Pat Gleeson

It looks like Channel 4HD are going to use DVB-S2:

http://www.digitalspy.co.uk/forums/showpost.php?p=48030807&postcount=119

watty

Some very old transponders might be class C and thus only work with FM analogue. If a transponder works on QPSK it should work on 8APSK though more linearity is needed. But Astra 2D is modern enough.