clarification on DVB-T card

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haloo101

77 posts

Master Geek

#25461 21-Aug-2008 22:49

I recently bought Wintv-1700 card and been told that it can only play either ONE digital or ONE analogue channel at one time.
but I just realised that while i was watch/record tv one, i can also watch TV2 , TVNZ 6, 7 and sport xtra (but not tv3), I was very surprise.

And i took me almost two weeks to figure this out.
So i am just wondering
1. what is the difference between all this Wintv XXXX card?
2. Why can't i watch tv3 while i record tv 1

Thanks

amphibem

138 posts

Master Geek

#158833 21-Aug-2008 23:09

Trust me your not alone in getting this pleasant suprise!

It comes down to how digital television works, on any one frequency (a 'mux') mulitple channels can be sent, up to a throughput limit. So with FreeviewHD there are 3 muxs with the channels distributed so:

TVNZ: TV1, TV2, TVNZ 6, TVNZ 7, Sports Extra
Mediaworks: TV3, C4
Korida: Parliment TV, Maori TV, FreeviewHD channel, Radio NZ channels

What this means is with any DVB-T tuner (i.e. nothing special about your card) you can record any of the above combinations at once as it only tuning one frequency, as long as your software supports it. I assume you are using Mediaportal as to the best of my knowledge only Mediaportal and Mythtv support this very handy feature.

Does that answer your questions?

Desktop: 5200 X2 - 3GB - 320GB - Nvidia 8600GT - Vista Home Premium - PVR150 - MediaPortal 1.0
My HTPC Blog - HTPCnz, the Home Theatre PC Resource

haloo101

77 posts

Master Geek

#158834 21-Aug-2008 23:14

wow so i could record TV1, TV2, TVNZ 6, TVNZ 7, Sports Extra or TV3 , C4 all at once?
or is there limit?

Thank you

amphibem

138 posts

Master Geek

#158836 21-Aug-2008 23:17

There is theoretically no limit, in reality you would eventually run out of hard drive or bus bandwidth though. But given even an 1080i stream uses only 1.2MB/s (out of at least 40MB/s a modern hard drive can sustain) I think your machine will have greater bandwidth than any one mux. So without multiple tuners you are highly unlikly to run out of system performance.

So yes, you could record all 5 TVNZ channels at once.

Desktop: 5200 X2 - 3GB - 320GB - Nvidia 8600GT - Vista Home Premium - PVR150 - MediaPortal 1.0
My HTPC Blog - HTPCnz, the Home Theatre PC Resource