Thursday, October 23, 2008

Digital Versus Analog Television

With all the hype of the impending DTV transition, many people are left wondering, "How do I know what kind of TV I have?"  This blog post will attempt to answer that question.  I must give you fair warning though; I am not an electrician or a television repair person so I will try to explain the difference to the best of my ability.  To help me make sense of the difference between the two types, I consulted www.howstuffworks.com and did a search for television. 

I'll start with what I found on analog television first.  Aside from the type of signal the television can receive, an analog television set usually looks a lot like the one below.  


As you can see from this picture I got from www.howstuffworks.com, the inside of a television is quite complex.  Someplace among the wires above is an analog processor, which converts the frequency waves into usable information.  Once the analog signal is received and processed, the cathode ray tube (located at the back of the set) a beam of electrons onto the screen.  Right in the middle of the picture above, there is a big bundle of copper wires.  These wires create a magnetic field that moves the electron light beam all over the screen.  Once the electrons hit the screen, which is made of phosphor, the screen begins to glow and broadcast the picture to the viewer.  Although this is an older type of television and most analog televisions look like this, there may be some cathode ray tube televisions on the market today that actually have digital processors in them.    

In a digital television, the signal is received as a small packet of information rather than in a frequency wave.  Because of the type of signal being received, a different type of processor is needed to broadcast the information on the screen.  Nearly all of the televisions being sold today already have those processors in them, but for some of the older models, which may have only be boughten a year or so ago, still only have the analog processor in them.  Most of the digital televisions today come with a LCD or plasma screen because they produce a better quality picture to broadcast the digital signal.  These televisions are normally lighter and flatter because they don't have to include tube and copper wire design as shown above in the cathode ray tube picture.  If you are going out to buy one of these types of televisions, I would do some homework first to the different types and what they offer before making a purchase to ensure you are getting the best television for your money.      

For those of you not in the market for a new television, a good test to know if you have a digital or an analog processor in your current television is to find out when one of the local stations will be shutting off their analog signal for testing purposes.  When they do, hook up the antenna and see if your television still picks up the signal.  You could also check the instruction manual (if you still have it) to see if it says anything about a digital processor in it.  If you don't have the manual, I would also recommend running a channel scan to see if your television gives you the option for a digital scan.  

I hope I haven't lost anyone in this sea of television technology.  Television is a complicated process and doesn't really need to be understood to enjoy.  However, if you would like to find out more about the LCD and plasma televisions or to get a better understanding on how television works, I would recommend checking out www.howstuffworks.com



1 comment:

Service Care said...

If you're subscribed to cable or satellite service, you've really got nothing to worry about with the transition to digital TV. They're supposed to handle that, no matter how old your television is (the digital tuner will be built in to the cable or satellite box).

If you're using rabbit ears or some other type of over-the-air antenna, you are probably going to need a new television or a converter box to receive digital TV when the change comes (Feb. 17, 2009). Nothing to panic about, but it's now time to really start moving towards a new TV or a converter, or you'll be wondering where your shows went pretty darn soon.