Re: Is HDTV really user friendly?

On Tue, 09 May 2006 16:01:19 GMT, Jeff Rife <wevsr@xxxxxxxx> wrote:

Roger (Delete-Invallid.stuff.groups@xxxxxx) wrote in alt.tv.tech.hdtv:
The receiver works much like a computer on a network. You can remove,
or briefly interrupt the signal and the computer will still be able to
rebuild the information. I'm not sure how much duplication exists in
the digital TV signal, but I doubt it's a lot and the set does not
have the capability to ask the satellite to resend the last packet
like the computer does.

There are 86,000 packets per second (give or take) in an ATSC transmission,
and there is enough error correction that any 512 of them can be lost and
still not lose a single pixel of the picture. I don't know what that

Thanks for that information. So it is very much like the computer
network with the exception the set can not querry the transmitter.

amounts to exactly, but it's quite a lot (relatively). These first 512

It's a lot more than I expected. <:-))

are "correctable errors", while any others are "uncorrectable".

I regularly run with zero errors of any kind on all my channels, so with
any reasonable signal strength, you are fine. I've tested my setup and
with 36dB of raw signal attenuation I only lose about 8dB S/N on most of
my channels, and that still keeps them above the required threshold, so
I've got a lot of headroom.

Again,
Thanks

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com
.

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