Vintage TV with thick glass front.
Stokkete / Shutterstock.com

Once upon a time, the TV could generate noise that lifted the hair up and even allowed to torment siblings with static attacks reminiscent of comic-book villains. But not so much today. Where are the disturbances?

This is why old TVs were so static

To understand why old televisions had the power to get your hair out of your head if you bent down, turned your cat into a pointed mess if it walked by and rubbed the screen, and gave you the power to fire people (or yourself) with a single touch, we need to investigate how these old CRT behemoths were working.

First, let’s look at the cutout diagram of the inside of a CRT TV to identify the key parts of a good old-fashioned 20th century TV.

CGI ray-tray rendering showing the internal operation of a CRT TV.
Søren Peo Pedersen / Wikimedia.org

First, we have a series of electron guns (1) that shoot a beam of electrons (2) from the back of the tube towards the beam mask (3) that separates the red, green, and blue elements of the image. The beams pass through the very fine mesh of the beam mask and strike the phosphor-coated inside of the TV window (4). The magnification of the inset (5) shows how the beams hit the phosphor layer and excite the phosphor that creates this iconic TV glow.

The whole process was very energetic. In fact, if you’ve ever heard someone warn you about opening your old TV because the shock could potentially stop your heart, they were giving you some reasonable advice.

Old kits contain a transformer that sends a high voltage electric current to power the electron gun. This continuous game of electrons hitting the metal screen behind the thick TV pane generates a positive static charge. If left alone, the static charge will slowly dissipate into the room, but if you bring something negatively charged to the screen (such as your hand), the object will be pulled to the screen.

At fairly low levels you will feel the charge as a kind of static hum or pull, at higher levels you may even hear a little creak as your hand moves across the screen and if the build up of static electricity is high enough it will “pop out” off the screen and “jump” You.

That’s why old TVs felt so dusty all the time. Dust particles floating in the air near the TV were attracted, as if the screen were a vacuum cleaner, all the way to the glass.

Why are new televisions not so static

Modern lounge with large flat screen TV.
Dariusz Jarzabek / Shutterstock.com

It would be a mistake to say that the newer flat screen TVs have no distortion at all. All electronic devices working will generate some noise.

But unlike a giant cathode ray tube that emits a continuous stream of electronics towards the glass in an old TV set, modern TVs are much slimmer (and less powerful) without so much ejection of electrons.

Instead of using a lot of energy to excite the phosphor layer covering a thick piece of glass, modern televisions instead use much less energy to signal the on and off of individual tiny pixels in a very fine mesh.

Exactly how this pixel array works and how specific signaling is handled varies with flat screen technology. However, the general assumption is whether we are talking about an old flat computer monitor or a shiny new OLED TV.

So, while both the old CRT and the new flat screen TV use electricity, the amount used in modern TVs is much less and is not used in such a way that it generates a significant electrostatic charge on the screen surface.

You’ll still have a little more dust on the body of a flat-screen TV than on a similar, but not electronic, object placed in the same place, but most of that is attracted by the plastic body of the TV rather than the screen as it would have been in the past.

Not only will this save you vacuuming, you will also save on energy. Modern televisions, even those dominated by living rooms, have a much lower operational load and phantom power than older televisions. Thanks to this, you save time for vacuuming, you do not hit the screen and you save money on electricity bills, while enjoying a picture with a much higher resolution.



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