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Julian Hall wrote: > Dave wrote: > >> Yes when I said minor glitch I meant Pixelate (I just couldn't think of the >> word!!) as well - Haven't had complete loss as yet. >> >> As you say hopefully once the dust settles (although I thought it had for >> us) things might be better. >> >> Regards, >> Dave. >> > Hi Dave, > > Not wishing to put a dampener on things but I've had digital (cable via > ntl/virginmedia) for just under ten years and it pixellates even now > occasionally. I think there are three main causes; > > Can't say I've had any problems with Virgin Media TV (/me runs and touches lots of wood). The phone line on the other hand is a different story! > a) signal strength - through air digital may be more prone than cable > Well it is prone to interference and the signal getting blocked by maybe buildings, hills etc. > b) atmospherics - see above > I used to find this would happen on analogue were we'd get interference from French TV transmitters. Yet to see if it happens with digital. > c) bandwidth - not sure which is better on this one, but logically 60 > million people pulling the same programme at once would pull more than 2 > million, and the signal would get a bit choppy I would suspect due to > data loss. Not sure what bandwidth (data capacity) is available in 'to > air' TV? > > Nah I don't think this would affect it. I mean terrestrial TV is one way, it's sent out and the aerials lock on to the signal and decode it. It's not as if there are 60 million connections to a server (or servers). I'd say it's the same for satellite too, the signal is sent out and the boxes pickup the signal. Where cable is concerned I would assume they would use some sort of multicasting technology to distribute the signal, that is if it doesn't already work in a similar way to digital terestrial or satellite TV. Rob -- The Mailing List for the Devon & Cornwall LUG http://mailman.dclug.org.uk/listinfo/list FAQ: http://www.dcglug.org.uk/linux_adm/list-faq.html