Saturday, May 15, 2010

LCD TV Problems - How You Can Fix Them Fast


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There are many reasons you could be having problems with your LCD TV. The thing to remember is that these things are microprocessor based, just like your computer. That means that at the first sign of trouble you should do the same thing you do with your computer; reboot it! That's right, if your LCD TV is dead ir unresponsive, turn it off with the remote or power button, wait about 10 seconds, then unplug it from the wall. After about 1 minute, plug the power back in and turn the TV on again. With any luck, your TV is now fixed. The next thing that causes problems with all new TVs, not just LCDs is the HDMI connection.

You see, HDMI is a fantastic way to get high definition video, but it's so good that the content providers were worried their stuff would end up out on the Internet in pure form, easy to copy and distribute. To prevent such an occurrence, a copy protection scheme called High Density Copy Protection (HDCP) was developed. This is an electronic data handshake system where the source and display devices have to recognize each other and agree that it's okay to send video. If there is no handshake, or the process gets corrupted in some way, poof, no more video. This problem was extremely prevalent in the early days of HDMI, but has been steadily improving since about the end of 2007 or early 2008.

If you are having problems with your TV, it may actually be an HDMI related issue. Here are some of the problems you might encounter.

Problem 1: No Picture
If you see, or rather don't see this, then shut everything down and then restart the system. Make sure all the connections are in place first. Look at the screen. If you see a resolution notice chances are the DDC line has communicated between source and sink. Good news for you! The problem is likely video related.

Problem 2: Flashes, No Audio, Pink Screen
No audio accompanied by a pink screen is usually indicative of a DDC communication problem. What's that mean for you? To check this, power up the system while all the HDMI cables are connected. If possible, try using shorter cables. Here you need to see if the system works at all. If for some reason the system still fails to come on, try using different inputs. You may find that your cable box will work and your DVD may not or vice versa. This can happen because of stray capacitance on the DDC line inside the HDMI cable. This may actually be caused by the hardware itself. If you think it may be, try getting a DDC line conditioner. Normally, these types of problems completely go away when conditioning is introduced.

Problem 3: Sparkles in the Picture
This is normally a video data transmission problem. Typically data transmission problems with HDMI are cable related. It could be that the cable is underperforming due to its length. This is especially common with cheap cables. Remember the HDMI spec says cable length should not exceed 10 meters. Shortening the cable should improve the signal integrity. Another possibility in this situation is a bad connector. HDMI connectors are notoriously fickle anyway.Try a new cable at each position along the signal path.

Symptom 4: Picture Comes On, Then Goes Off
Typically, this is caused by one of two things. The first is when one or more of the video TMDS channels has a high bit error rate or is not working at all. Next is when the DDC line doesn't quite make it. In that case, the HDCP is not getting a new refresh key. Buy a in a better quality cable with larger wire. When it comes to wire gauge, smaller gauge equals bigger wire diameter. Hence 20 gauge is larger diameter than 24 gauge.

If you're having LCD TV problems, check these things before you call a TV repair company. In many cases you can easily fix the problem yourself without spending a fortune.

Recommend : TV buying guide LED television

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