For years, people have heard that watching a movie on a high-definition (HD) set is like looking out a window. The picture is sharper, clearer and more detailed than anything you’ll see on an older, standard-definition (SD) set. It’s supposed to be a revolution on par with the jump from black and white to color.
But after all that hype, the experience of watching a brand new HDTV can be a little anticlimactic. If you just plug it in and start watching, you might be disappointed with what you see. The picture might look pretty good but seem brighter or more unnatural than it did in the store. Or, it might be pixelated, distorted or fuzzy and not look good at all. Why does this happen? HDTVs are supposed to be better than old, analog TVs for two reasons:
- HDTVs can use digital signals made of ones and zeros rather than analog signals made of fluctuating waves. Digital signals aren’t prone to static, interference or ghost images like analog signals are. They do a better job of carrying the information that makes up the picture.
- HDTVs have a higher resolution than analog sets. They can display images with far more detail than traditional TVs can.
Fortunately, it’s easy to get better performance from your HDTV. All it takes is a few minutes to configure everything correctly and a little knowledge about what kinds of programs will look best.
“Radio waves” transmit music, conversations, pictures and data invisibly through the air, often over millions of miles — it happens every day in thousands of different ways! Even though radio waves are invisible and completely undetectable to humans, they have totally changed society. Whether we are talking about a cell phone, a baby monitor, a cordless phone or any one of the thousands of other wireless technologies, all of them use radio waves to communicate.
Here are just a few of the everyday technologies that depend on radio waves:
- AM and FM radio broadcasts
- Cordless phones
- Garage door openers
- Wireless networks
- Radio-controlled toys
- Television broadcasts
- Cell phones
- GPS receivers
- Ham radios
- Satellite communications
- Police radios
- Wireless clocks
The list goes on and on… Even things like radar and microwave ovens depend on radio waves. Things like communication and navigation satellites would be impossible without radio waves, as would modern aviation — an airplane depends on a dozen different radio systems. The current trend toward wireless Internet access uses radio as well, and that means a lot more convenience in the future!
The funny thing is that, at its core, radio is an incredibly simple technology. With just a couple of electronic components that cost at most a dollar or two, you can build simple radio transmitters and receivers. The story of how something so simple has become a bedrock technology of the modern world is fascinating!
