Our tuners meet the specifications of what is required of the tuner broadcast spectrum in the U.S. That testing has been extensive, and as a result, very few problems have been reported.
I called Comcast this afternoon to see what they knew about these kinds of issues. While they keep HD broadcasts "open" (unscrambled), they do say that they don't guarantee that the signal coming in will work on every television. The variables included wiring, transmission, length from last repeater, among other things. Typically they will transmit local HD channels in high definition, but the customer support supervisor that I spoke with today noted that if customers have problems, and it's not uncommon without a box to have problems with HD programming, they highly recommend a HD box to maintain signal and strenth, which produces a stable, consistent picture quality.
HD programming takes more bandwidth. You may have great bandwidth transmissions with SD. But the information required to dry-line transmit HD feed is much harder. The cable companies know this, and that's why the box is an essential part of their HD offering.
Comcast notes that an HD box is required for HD programming on their website:
http://www.comcast.com/Customers/FAQ/FaqDetails.ashx?Id=177&lid=4FAQNeedforHdtv&lpos=TopFAQs
They do note, however, that "some customers can receive the unscrambled signals through the coax, and some can not. Those that can't, we recommend a cable box".
With digital tuners, if the signal isn't strong, the tuner may change to an available channel, thus, the channel changing. In the old analog tuners, you'd just get static. I'm not sure why the channels are changing for sure, but I'd suspect that when the television can't process the picture, it defaults to the next channel. Any other input would note that a "signal is not available", however, the signal is available; it's just not offering enough of a feed that can be processed properly.
Besides improving picture quality, a cable box would also likely calibrate the sound so that there is no delay or echo. That's the reason they have those boxes available - so if the delivery isn't strong, you have an option to improve your signal. What you're seeing is the new digital version of what used to be analog static.
Not to mention, many of those cable boxes have an optical out, which would allow you to get surround sound directly to your Durabrand when that signal is transmitted.
When you can fix two out of three transmission issues with a cable box, it's hard to suggest that the TV is the problem. And my best hypothesis is that the third symptom (channel changing) is the result of the picture signal not being strong enough.
Ask your cable provider if you can try a box free for a week and see if those issues don't disappear.
I can appreciate your frustration. Hey, I've been there too. At the same time, let's try and work together to find a solution.
--HDTech
Okay, I thought Samsung was among the best out there when it comes to LCD TVs, at least CNET reviews praise it. However, I'm now on my second TV in less than a month and it's driving me nuts! Sorry for all the yelling, but I'm frustrated.
The situation is as follows. I don't use a cable box (Comcast is my cable company) and I subscribe to only basic extended channels. So, all in all I have my coax cable fed straight into the TV. I also have the firmware of this bad boy upgraded to the latest available (ver. 1006 I believe). The damn thing simply switches channels on me several times in the span of an hour. I would be watching HD channel 1-5 with 1080i resolution and all of a sudden it will flip to a lower channel no matter where my remote is at the time. It's not the remote control because I hid it and it still does it! I'm, like I said, on my second TV now with same issues.
Another annoyance is the fact that sound is unstable, it just starts to echo at commercial time when any particular commercial starts to play. I have the TV hooked up to my home theater system, made by Durabrand, one of those cheap 5.1 surround systems, but I'm sure it's not my home theater that does it. The reason why I say that is because when I hear it to start to echo I can either switch to another channel or change the entertainment mode to off and then back to on and the sound problem is fixed (until the next commercial brake). I turned the TV sound off in the menu because that always interferes with the home theater system's sound quality and would constantly echo if not turned off.
Any bright ideas what to do? I'm afraid that this particular TV model is a lemon and Samsung is selling us stuff that isn't even tested properly. How else would you explain that two brand new TV sets, all manufactured in August of this year, both have identical issues?
Thanks in advance for any suggestions.
--Croatian

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