Why don’t TVs have constant white noise anymore? | Tech Reddy


An old TV showing white noise filled with picture.
Peter Gudella/Shutterstock.com

TV static, that snowy white noise, was a staple of the 20th century television experience, but it’s now a thing of the past. Where did it go?

Why did old TVs have static?

Call it static, white noise, or snow—if you’re a student of a certain age, you’re more than familiar with the pounding and constantly changing chaotic noise you don’t see when you tune your TV to unused channels.

There’s a good chance that most of our young readers have never encountered that white noise and static anywhere other than seeing it featured in old movies or the iconic HBO intro reel.

To understand what static TV was, you need to understand how analog TV works. The easiest way to understand how old televisions worked is to think of them as radio-with-pictures.

Unlike how the radio station in your city may sound clean and clear when you’re at home but full of white noise and sounds when you’re driving over the hill and through the woods to your grandmother’s house far outside the city limits, analog. Television signals ranged from very strong to barely available.

And, just like old radio, when you turned on analog television to a station that wasn’t in use in your area (or, in the old days, it was tuned to the night), your television was still trying to tune in. signal, there was no suitable TV broadcast to be found.

Instead, without an actual station signal to be locked to, the TV can “play” the radio source around it.

The visible and audible white noise, also called snow or static, produced by old analog televisions was a combination of electrical noise inside the television itself, radio waves from the local area, and, believe it or not, background radiation since the birth of the television. in the universe.

No, really, some of the static that old television shows is gamma radiation from the Big Bang which, over billions of years and the expansion of the universe, has become microwave radiation. A small amount of that radiation hits the Earth, passes through our atmosphere and shows up as analog TV.

Although many people have found the white noise of the TV to be soothing, the static that has recently been highlighted – that the images of snow and the hiss of radiation of space and deep space – play a big role in how often the TV static is presented as a conspiracy. scores for movies and TV shows.

You will often come across examples of TV static being used to show the presence of ghosts or the presence of supernatural forces or characters who can sense static. For example, an episode of The X-Files (S01E04, “The Conduit”) featured a boy who was able to decipher what the non-television radio signals displayed on his television were communicating.

Here’s why today’s televisions don’t have Static by Design

Modern TV set with "No Sign" message on the screen.
Jason Fitzpatrick / How to Geek

To understand why today’s TVs don’t have that cool white noise, we need to turn our attention to the history of TV in the 20th century and instead look at the seismic changes in the way TV broadcasts took place in the early 21st. century.

In 1996, the United States Congress passed the Communications Act of 1996, which, among other things, included the transition from analog to digital television transmission to free up a wide range of radio frequencies for other purposes, including cellular communications and services. urgent.

While the final sunset date for the end of analog TV broadcasts was moved from the original date specified in the Telecommunications Act several times, on June 12, 2009, all high-power analog stations in the United States switched to digital signals.

Because of that change, modern televisions do not have analog channels. When you turn on modern television with a digital device to a channel that is not available, there is nothing but a blank screen, with the message “No Signal” – not a little snow to be seen.

Best Indoor Antenna

That’s because digital TV signals are two. Either the antenna can pick up the signal and produce a picture, or it can’t. No static, no spooky fading in and out, or any of the residue of analog television.

Since there is no reason to show a missing signal, today’s TVs have chosen to show you a blank screen, sometimes with additional information and instructions – like the screen of the Samsung smart TV seen in the photo above. If your antenna breaks or something causes incredible interference, you don’t see static or grainy washed out version of the show you’re watching, it stutters, pixelates, and fades.

On the downside, that means you either get a certain channel or you don’t. Inside, the switch to digital TV allows us to enjoy HD video over the air without worrying about high-speed internet or blowing through video streaming data caps.

Interestingly, there are notable exceptions to this dual channel representation. Most LG models show static instead of a simple “No signal” screen. If you happen to have an LG TV that freaks out with static when you turn it on, you can fix the problem by looking in the settings menu under Channel Tuning and changing the manual tuning option to “Cable DTV” so that the TV doesn’t have to constantly scan for dead air every time you turn it on.

Apart from this unusual deviation option, you have a great chance of having a smart TV with a “black mirror” effect of just showing you a blank black background when there is no signal.


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