Re: signal breakup

On Sun, 09 Nov 2008 11:49:33 -0500, Mason Barge <masonbarge@xxxxxxxxx>
wrote:

On Sun, 9 Nov 2008 10:58:47 -0500, "Dan D. Err" <dander@xxxxxxxxxx>
wrote:


"Russell Watson" <russell-watson@xxxxxxxxxxx> wrote in message
news:2i0eh4h7nt7ri4ntkheftvms4tafsc97f5@xxxxxxxxxx
On Sun, 9 Nov 2008 06:45:36 -0500, "Dan D. Err" <dander@xxxxxxxxxx>
wrote:


I've been experiencing a lot of signal degradation, the blockiness, lags
and complete cutoff of signal to black screen. [Rogers Cable in Ontario].
It
varies from channel to channel though some of most commonly affected seems
to be BNN [Canadian Business News], KTLA [LA CW affiliate] WUTV [Buffalo
Fox
affiliate] and this moring WGRZ [NBC Buffalo affiliate]

Does anyone know if this sort of thing is Rogers at the source, Rogers
digital box. or the originating station?

I once tried complaining to Rogers but that got the response you would
expect from a de facto monopoly.


Are you on digital cable?

Ya.

My analog cable has been fine but I stopped
at my sister's yesterday and her signal was doing exactly what you
describe. She has Comcast digital in FL.

It's definitely the digital type of blocky breakup rather than the analog
snow. I have a digital box. I also have internet through them and I wonder
if 'bandwidth' or whatever governs coax capacity might be the problem. But
the problem only seems to occur on certain channels, mostly KTLA [332], BNN
[57] WUTV [28] and this weekend NBC [11] and for a few minutes ABC [6]

I'm not a tech guy, but I've heard that this stems from breaking up
single channels into multiple channels. This either leaves
insufficient bandwidth and/or too much compression for the signal. My
guess is that in some cases, problems with signal quality start
showing up.

In other words, the cable companies have gotten so greedy for
bandwidth that they have used digital technology to make your picture
worse. There goes all the lies about digital's purpose being to
"increase picture quality".

Digital was never about giving you better picture quality. It can do
that if you have noise in the system or bad cable connectors that can
allow ghost signals to get in. What digital does do is give them the
ability to add more services on the same cable. Originally it was just
increased channel count(including music channels), then came broadband
service, then HD video and finally digital phone service. So it's a
way for the cable company to take the same plant and get more money
out of each customer.

(Yes, when things were turned on in each system will vary, and the
cable companies did spend money on improving the plant to get better
signal quality and higher bandwidth, but the gist of the story remains
the same. It's all about increasing revenue.)

Multiplexing of channels has been done for ages. It was a great way
for satellite services to deliver more channels to each home and it's
been the same for cable. The problem is they (at least Comcast) seems
to have settled on 12 channels per cable channel multicast (as in one
cable channel frequency will carry 12 digital channels) which is
probably 1 too many. You won't always notice problems but they do show
up on occasion when there's not enough bandwidth to handle all of the
channels needs.

The other issue that can cause problems is if there is any noise or
interfering signal on the cable. With an analog signal it might cause
a bit of noise in the video or audio (like when they do a cable signal
sweep to look for trouble), but the channel will still be watchable.
With digital you can get the green macroblocks showing up,
pixelazation, audio dropouts or in the worst case the picture may
freeze or disappear. It's a tradeoff of the types of problems that the
viewer will face and since most customers want more channels/services
the cable company has chosen to go digital, and they are slowly
switching all of their channels over to digital. Eventually everything
will be in digital.

.

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