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Why Inventing Color TV Was So Hard · The Infographics Show Podcast

• 0:10
  Speaker 1: You know, when you when you sit down in your
• 0:16
  Speaker 1: living room today and turn on a sleek, incredibly thin
• 0:20
  Speaker 1: flat screen TV, or when you pull your smartphone out
• 0:23
  Speaker 1: of your pocket to watch a video, there's just this
• 0:26
  Speaker 1: expectation of like silent, seamless magic, right.
• 0:30
  Speaker 2: Yeah, it's just glowing pixels.
• 0:32
  Speaker 1: Exactly, It's clean, it's completely safe. You tap a glass
• 0:35
  Speaker 1: screen and information just materializes out of nowhere.
• 0:38
  Speaker 2: I mean, we are entirely accustomed to displays being solid state,
• 0:43
  Speaker 2: quiet and well, perfectly harmless. The technology has become so
• 0:48
  Speaker 2: refined that it feels less like a machine and more
• 0:51
  Speaker 2: like pure information simply appearing on a surface.
• 0:53
  Speaker 1: You know, yeah, totally.
• 0:54
  Speaker 2: You don't think about the physical mechanics because frankly, there
• 0:57
  Speaker 2: are very few physical mechanics left to think about.
• 0:59
  Speaker 1: But if we read why in the Clock, the reality
• 1:02
  Speaker 1: of how we got here is absolutely wild. So welcome
• 1:05
  Speaker 1: to Kurskasak podcast Science Revealed. Glad to be here today.
• 1:08
  Speaker 1: Our mission is to uncover the dramatic, borderline absurd, and
• 1:12
  Speaker 1: surprisingly dangerous history behind a device that revolutionized the entire world,
• 1:17
  Speaker 1: and that is, of course, the color television.
• 1:19
  Speaker 2: It is a bizarre chapter in the history of technology.
• 1:23
  Speaker 2: I mean, it's a story of vicious corporate warfare, engineering
• 1:27
  Speaker 2: challenges that seem physically impossible to solve, and a piece
• 1:30
  Speaker 2: of consumer electronics that was, at its core kind of
• 1:33
  Speaker 2: a monster.
• 1:34
  Speaker 1: Yeah, a literal monster. To give you the listener an
• 1:37
  Speaker 1: idea of how crazy this gets, especially if you're a
• 1:40
  Speaker 1: high school student who only knows iPads and led screens
• 1:43
  Speaker 1: before the flat screens you have today. The United States
• 1:47
  Speaker 1: government actually banned the production of color TVs.
• 1:50
  Speaker 2: Which is just wild to think about.
• 1:52
  Speaker 1: They were terrified that this new technology would completely ruin
• 1:56
  Speaker 1: the existing television network. And here's the craziest part. The
• 2:01
  Speaker 1: very first commercial color televisions actually relied on a literal,
• 2:06
  Speaker 1: physical spinning plastic wheel clattering around inside a giant wooden
• 2:11
  Speaker 1: box in your living.
• 2:11
  Speaker 2: Room, which I know sounds like a joke, but it
• 2:13
  Speaker 2: was a completely real, heavily debated national standard.
• 2:17
  Speaker 1: We'll get into that spinning wheel soon, I promise.
• 2:19
  Speaker 2: Yeah. Today, we're going to explore how television actually works
• 2:22
  Speaker 2: at a fundamental, sub atomic level. We'll look at the
• 2:26
  Speaker 2: intense color war between rival broadcasting corporations, the genius mathematical
• 2:30
  Speaker 2: trick that finally brought color to the masses without breaking
• 2:33
  Speaker 2: the airwaves. And the incredibly complex and honestly terrifying engineering
• 2:38
  Speaker 2: of the cathode ray two sounds like a plan.
• 2:40
  Speaker 1: Oh real quick. If you're enjoying our educational journeys here,
• 2:43
  Speaker 1: please take a second to rate krisgasok podcast Science Revealed
• 2:47
  Speaker 1: five stars. It really helps the show and we hugely appreciate.
• 2:51
  Speaker 2: It, definitely. Five stars is a way to go.
• 2:53
  Speaker 1: Okay. So to understand this massive corporate war over color,
• 2:57
  Speaker 1: we first have to understand the canvas they were fighting over. Right,
• 3:01
  Speaker 1: Let's look at the absolute powerhouse of the post WWII era,
• 3:06
  Speaker 1: the black and white television boom. What exactly was sitting
• 3:09
  Speaker 1: in everyone's living room back in the late nineteen forties
• 3:11
  Speaker 1: and early nineteen fifties.
• 3:13
  Speaker 2: So the foundation of all early television was a massive
• 3:15
  Speaker 2: piece of hardware called the cathode ray tube or CRT.
• 3:18
  Speaker 1: The dreaded heavy box.
• 3:20
  Speaker 2: Exactly, if you grew up with an older, incredibly heavy,
• 3:24
  Speaker 2: deep television set, the kind that took two people to
• 3:27
  Speaker 2: lift and took up half the living room, you were
• 3:29
  Speaker 2: looking at a CRT. And at its core, it is
• 3:32
  Speaker 2: a giant, thick glass vacuum tube.
• 3:36
  Speaker 1: A vacuum tube. Let's pause on that. We hear that
• 3:40
  Speaker 1: term thrown around in old sci fi movies, but what
• 3:42
  Speaker 1: does it actually mean in the context of a TV.
• 3:45
  Speaker 1: You're saying all the air has been completely sucked out
• 3:47
  Speaker 1: of this massive glass box.
• 3:48
  Speaker 2: Essentially, Yes, the inside of a CRT is evacuated to
• 3:52
  Speaker 2: less than a millionth of normal atmospheric pressure.
• 3:55
  Speaker 1: Wow.
• 3:55
  Speaker 2: Yeah, it is a near perfect vacuum. And the reason
• 3:57
  Speaker 2: you need a vacuum is because you are dealing with
• 3:59
  Speaker 2: so ab atomic particle, specifically electrons.
• 4:02
  Speaker 1: Right, Because if there were air in.
• 4:04
  Speaker 2: There, if there were air molecules inside that glass tube,
• 4:07
  Speaker 2: the electrons would crash into the oxygen and nitrogen atoms,
• 4:11
  Speaker 2: scatter in every direction, and just lose all their energy.
• 4:13
  Speaker 2: You need an empty highway for them to travel.
• 4:15
  Speaker 1: Okay, so we have an empty glass highway. Where do
• 4:17
  Speaker 1: the cars. The electrons come from.
• 4:19
  Speaker 2: Inside the narrow back end of this tube, which is
• 4:22
  Speaker 2: called the neck, sits the electron gun. The engineering here
• 4:26
  Speaker 2: is fascinating. It starts with a tungsten filament very similar
• 4:30
  Speaker 2: to the tiny coil inside an old school incandescent.
• 4:33
  Speaker 1: Light bulb, like the ones that gets super hot Exactly.
• 4:36
  Speaker 2: The TV runs an electrical current through this tungsten coil,
• 4:41
  Speaker 2: and it gets incredibly hot.
• 4:42
  Speaker 1: How hot are we talking?
• 4:43
  Speaker 2: Upwards of a thousand degrees celsius?
• 4:46
  Speaker 1: Wait? Really inside the TV?
• 4:48
  Speaker 2: Yes, right inside your living room. This filament is placed
• 4:51
  Speaker 2: directly against or inside a small Menner cylinder called the
• 4:56
  Speaker 2: cathode okay, and the cathode is coated with special chemicals,
• 4:59
  Speaker 2: usually mixtures of barium and strontium oxides. When this castode
• 5:04
  Speaker 2: gets superheated by the tungsten filament, the thermal energy is
• 5:07
  Speaker 2: so intense that the electrons in the outer orbits of
• 5:10
  Speaker 2: those barium and strontium atoms get too energetic to stay attached.
• 5:14
  Speaker 2: Oh I see, They literally boil off the surface of
• 5:16
  Speaker 2: the metal into the vacuum.
• 5:18
  Speaker 1: I love that visual. So you're just heating up metal
• 5:20
  Speaker 1: until the electrons vibrate so violently they pop right off
• 5:23
  Speaker 1: into empty space.
• 5:24
  Speaker 2: The technical term is thermionic emission. It creates a sort
• 5:27
  Speaker 2: of invisible cloud of free floating electrons just hovering around
• 5:32
  Speaker 2: the hot cathode.
• 5:33
  Speaker 1: But a cloud doesn't give you a picture, right.
• 5:35
  Speaker 2: A cloud is useless for a picture. You need a beam.
• 5:38
  Speaker 2: So the electron gun uses a series of metal cylinders
• 5:41
  Speaker 2: with high positive electrical charges.
• 5:44
  Speaker 1: Because electrons are negatively charged.
• 5:46
  Speaker 2: Exactly because electrons have a negative charge and opposites attract
• 5:51
  Speaker 2: these free electrons are violently yank forward by the positive charge.
• 5:55
  Speaker 2: They are shape focused and accelerated into a tight, incredible,
• 6:00
  Speaker 2: fast moving beam.
• 6:01
  Speaker 1: And this invisible beam is being fired straight across the
• 6:04
  Speaker 1: vacuum of the glass tube toward the front screen. The
• 6:06
  Speaker 1: part of the viewer is actually looking at what happens
• 6:09
  Speaker 1: when it hits the glass well.
• 6:10
  Speaker 2: The inside of that front glass screen is coated with
• 6:13
  Speaker 2: a chemical compound.
• 6:14
  Speaker 1: Called a phosphor phosphor.
• 6:15
  Speaker 2: Okay, yeah, phosphors have a very specific property. When they
• 6:18
  Speaker 2: are struck by high energy particles like electrons, they absorb
• 6:22
  Speaker 2: that kinetic energy and release it as a visible light.
• 6:25
  Speaker 2: The electrons slam into the coating and the phosphor glows
• 6:28
  Speaker 2: brilliantly upon impact.
• 6:29
  Speaker 1: Okay, I follow the physics. If you're a high school
• 6:31
  Speaker 1: physics student. This is basically just converting kinetic energy into light.
• 6:35
  Speaker 1: But if I just shoot a beam straight ahead, all
• 6:38
  Speaker 1: I'm going to get is a single glowing dot right
• 6:40
  Speaker 1: in the dead center of the screen, right.
• 6:42
  Speaker 2: Just one dot.
• 6:43
  Speaker 1: So how does one single dot turn into a moving
• 6:46
  Speaker 1: picture of like a baseball game or a news anchor.
• 6:50
  Speaker 2: That is where the genius of the raster scan comes in.
• 6:53
  Speaker 2: The early television doesn't flash the entire picture onto the
• 6:56
  Speaker 2: screen all at once, the way a film projector shines
• 6:59
  Speaker 2: a whole frame of a movie onto a theater screen simultaneously.
• 7:02
  Speaker 1: Oh, it doesn't, not at all.
• 7:04
  Speaker 2: Instead, the TV draws the picture using that single solitary
• 7:08
  Speaker 2: electron beam.
• 7:09
  Speaker 1: Wait, it's literally drawing the image like a.
• 7:12
  Speaker 2: Pencil, line by line around the neck of the tube.
• 7:15
  Speaker 2: Just past the electron gun, there is a heavy copper
• 7:18
  Speaker 2: component called the deflection yoke.
• 7:20
  Speaker 1: Deflection yoke, got it.
• 7:21
  Speaker 2: It's essentially a set of powerful electromagnets. By rapidly changing
• 7:25
  Speaker 2: the electrical current running through these coils, the TV changes
• 7:29
  Speaker 2: the magnetic field inside the neck of the tube. Because
• 7:33
  Speaker 2: electrons are charged particles, their path bends when they pass
• 7:36
  Speaker 2: through a magnetic field.
• 7:38
  Speaker 1: Ah, so you can steer the beam precisely.
• 7:41
  Speaker 2: The magnets steer the beam, forcing it to sweep across
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  Speaker 2: the screen from the top left corner straight across to
• 7:47
  Speaker 2: the right, drawing a single horizontal line of glowing phosphor. Okay,
• 7:51
  Speaker 2: picturing it the moment it hits the right edge, the
• 7:54
  Speaker 2: beam turns off for a microsecond, what engineers call the
• 7:57
  Speaker 2: horizontal blanking interval, zips back to the left side, drops
• 8:01
  Speaker 2: down a tiny fraction of an inch, turns back on
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  Speaker 2: and draws the next line.
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  Speaker 1: It makes me think of the super fast, invisible high
• 8:08
  Speaker 1: tech typewriter.
• 8:10
  Speaker 2: That's a great way to think of it.
• 8:11
  Speaker 1: The electron beam is a typewriter key right, and it's
• 8:14
  Speaker 1: rapidly striking the screen, leaving glowing ink. The phosphor behind
• 8:19
  Speaker 1: it types a line, hits the carriage, return types the
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  Speaker 1: next line, hits return, over and over until it reaches
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  Speaker 1: the bottom of the screen exactly. But to create a
• 8:26
  Speaker 1: moving video that doesn't just look like a laser pointer
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  Speaker 1: drawing slowly, it has to be doing this insanely fast.
• 8:33
  Speaker 2: Oh, incredibly fast. To understand the scale, let's look at
• 8:36
  Speaker 2: the early American black and white television standard. It was
• 8:40
  Speaker 2: established by a group called the National Television System Committee,
• 8:43
  Speaker 2: or NTSC, back in nineteen forty one.
• 8:46
  Speaker 1: The NTSC will be hearing that acronym a lot.
• 8:49
  Speaker 2: Yes you will. They decided that a single frame, one
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  Speaker 2: complete picture, would be made up of five hundred and
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  Speaker 2: twenty five horizontal lines.
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  Speaker 1: Five hundred and twenty five lines for one picture.
• 8:59
  Speaker 2: Yes, trick the human eye into seeing smooth, continuous motion.
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  Speaker 2: The electron beam had to draw that entire five hundred
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  Speaker 2: twenty five line picture thirty times every single second, thirty.
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  Speaker 1: Times a second. So wait, if I do the math,
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  Speaker 1: five hundred and twenty five lines times thirty frames, that's fifteen,
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  Speaker 1: seven hundred and fifty horizontal lines being drawn across the
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  Speaker 1: screen every single second.
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  Speaker 2: That's the map.
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  Speaker 1: That is a staggering amount of mechanical and electrical speed
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  Speaker 1: for the nineteen forties.
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  Speaker 2: It really is, and it relies entirely on a biological
• 9:27
  Speaker 2: quirk of human vision. The phosphor glows for only a
• 9:30
  Speaker 2: fraction of a second before fading out. If you had
• 9:32
  Speaker 2: eyes that could process information at a microsecond level, you
• 9:35
  Speaker 2: wouldn't see a television show at all.
• 9:36
  Speaker 1: What would you see?
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  Speaker 2: You would just see a single impossibly bright white dot
• 9:41
  Speaker 2: frantically zigzagging back and forth across a dark glass screen.
• 9:45
  Speaker 1: That's so creepy to think about.
• 9:46
  Speaker 2: But because of the persistence of vision in your retina
• 9:49
  Speaker 2: and the way your brain processes visual data, your biology
• 9:54
  Speaker 2: gives up on trying to track the dot. It just
• 9:56
  Speaker 2: blends all those rapidly fading lines into a smooth, seamless,
• 10:01
  Speaker 2: moving black and white.
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  Speaker 1: Image that is mind blowing. The TV is relying on
• 10:05
  Speaker 1: our biological limitations to create an illusion. And you know,
• 10:09
  Speaker 1: there is a fun piece of trivia here about that
• 10:12
  Speaker 1: thirty frames per second number. It wasn't just a random choice,
• 10:15
  Speaker 1: was it not? At all?
• 10:16
  Speaker 2: It was tied directly to the American.
• 10:18
  Speaker 1: Electrical grid because of the wall outlets.
• 10:20
  Speaker 2: Right, the alternating current coming out of standard US wall
• 10:23
  Speaker 2: outlets cycles at sixty hertz or sixty times a second.
• 10:26
  Speaker 2: Early television engineers realized that if the TV's frame rate
• 10:29
  Speaker 2: wasn't mathematically synced to the power grid, any slight electrical
• 10:33
  Speaker 2: interference from the power lines would show up as a dark,
• 10:35
  Speaker 2: slowly rolling horizontal bar on the screen.
• 10:39
  Speaker 1: Well, I've seen that on old monitors.
• 10:40
  Speaker 2: Exactly. By sinking the TV to draw exactly half a
• 10:44
  Speaker 2: frame called a field sixty times a second, creating thirty
• 10:47
  Speaker 2: full frames a second, they perfectly masked that electrical hump.
• 10:52
  Speaker 1: It's the beautiful marriage of physics, electrical engineering, and biology.
• 10:55
  Speaker 1: And this system worked so well.
• 10:57
  Speaker 2: It was a massive success.
• 10:58
  Speaker 1: If we look at the historical context after World War II,
• 11:01
  Speaker 1: there was this massive, unprecedented economic boom. Millions of soldiers
• 11:06
  Speaker 1: returned home, started families, bought houses in the new suburbs
• 11:09
  Speaker 1: under the GI Bill. They had disposable income, and they
• 11:12
  Speaker 1: wanted entertainment in their living rooms.
• 11:14
  Speaker 2: And television was the ultimate modern marvel.
• 11:17
  Speaker 1: By nineteen fifty there were millions of these expensive black
• 11:21
  Speaker 1: and white CRT televisions sitting in American homes. The industry
• 11:24
  Speaker 1: was an absolute juggernaut.
• 11:26
  Speaker 2: The adoption rate was astronomical. In nineteen forty six, there
• 11:29
  Speaker 2: were maybe a few thousand televisions in the US. By
• 11:32
  Speaker 2: nineteen fifty one, there were over fifteen million, fifteen million YEP.
• 11:36
  Speaker 2: The entire broadcasting infrastructure, the camera equipment, the broadcast towers,
• 11:40
  Speaker 2: the home receivers was entirely built around this nineteen forty
• 11:43
  Speaker 2: one NTSC standard five hundred and twenty five lines, thirty
• 11:46
  Speaker 2: frames A second black and white.
• 11:48
  Speaker 1: Which sets the stage for our central conflict today. If
• 11:52
  Speaker 1: black and white was working so incredibly well, and the
• 11:55
  Speaker 1: industry was minting money selling millions of units, why did
• 11:59
  Speaker 1: television exis executives absolutely panic when engineers tried to add color. Well.
• 12:04
  Speaker 2: The panic was driven by that massive installed base. The
• 12:08
  Speaker 2: economic stakes were sky high. If you invent a completely
• 12:12
  Speaker 2: new way to broadcast a television signal to include color information,
• 12:16
  Speaker 2: you face an existential question, which is what happens to
• 12:19
  Speaker 2: the fifteen million existing black and white sets that people
• 12:22
  Speaker 2: just paid good money for?
• 12:24
  Speaker 1: Right a television in nineteen fifty was a massive investment.
• 12:27
  Speaker 1: It costs the equivalent of thousands of modern dollars. You
• 12:29
  Speaker 1: couldn't just tell the public, hey, sorry, throw that away,
• 12:32
  Speaker 1: we're doing color now.
• 12:33
  Speaker 2: Exactly do these millions of existing sets suddenly stop working?
• 12:37
  Speaker 2: Do they just show a blank screen when a color
• 12:39
  Speaker 2: program comes on? That was the hurdle. Any new color
• 12:42
  Speaker 2: system had to figure out how to navigate this massive
• 12:45
  Speaker 2: infrastructure of black and white technology.
• 12:47
  Speaker 1: You needed to play nice.
• 12:48
  Speaker 2: They needed what the industry called compatibility.
• 12:50
  Speaker 1: And this brings us to one of the most absurd
• 12:52
  Speaker 1: technological tangents we found in this whole story. To solve
• 12:56
  Speaker 1: this problem of adding color, one major broadcasting network see
• 13:00
  Speaker 1: came up with a solution that was, frankly a mechanical monstrosity.
• 13:05
  Speaker 2: It really was. It was called the CBS Field sequential system,
• 13:08
  Speaker 2: and it is a fascinating example of trying to solve
• 13:11
  Speaker 2: a highly complex electronic problem with brute force, practically nineteenth
• 13:16
  Speaker 2: century mechanical engineering like steampunk. Almost yeah, kind of. CBS
• 13:21
  Speaker 2: looked at the standard black and white CRT and thought,
• 13:24
  Speaker 2: what if we don't try to invent a new color
• 13:26
  Speaker 2: tube at all? What if we just take the perfectly
• 13:29
  Speaker 2: good black and white tube and put physical colored filters
• 13:32
  Speaker 2: in front of it.
• 13:33
  Speaker 1: Wait, hold on, you're telling me their solution to broadcasting
• 13:35
  Speaker 1: color in the atomic age was to literally bolt colored
• 13:39
  Speaker 1: glass to the front of the TV.
• 13:41
  Speaker 2: Yes, but it wasn't just a static piece of glass.
• 13:44
  Speaker 1: How does that even work for a moving picture?
• 13:46
  Speaker 2: Okay, imagine a normal, standard black and white television tube.
• 13:50
  Speaker 2: Now take a large physical wheel made of transparent plastic
• 13:54
  Speaker 2: or glass. Divide the circular wheel into segments like slices
• 13:58
  Speaker 2: of a pie.
• 13:58
  Speaker 1: Okay, I'm tracking color.
• 14:00
  Speaker 2: One slice red, the next green, the next blue, and repeat.
• 14:03
  Speaker 1: So I have a multicolored plastic wheel.
• 14:05
  Speaker 2: Now mount a powerful electric motor inside the wooden TV cabinet,
• 14:09
  Speaker 2: attach the wheel to it, and place this spinning wheel
• 14:12
  Speaker 2: directly in front of the glass screen.
• 14:15
  Speaker 1: I cannot emphasize enough to you, the listener, how ridiculous
• 14:19
  Speaker 1: this sounds. A literal physical spinning wheel of color inside
• 14:23
  Speaker 1: the TV.
• 14:24
  Speaker 2: Yes, the entire system relied on this mechanical rotation.
• 14:28
  Speaker 1: Wow.
• 14:28
  Speaker 2: The television camera at the CBS Broadcasting studio had an
• 14:32
  Speaker 2: identical matching spinning wheel in front of its lens. The
• 14:35
  Speaker 2: studio camera would look through the red filter and capture
• 14:38
  Speaker 2: a single frame of the scene.
• 14:40
  Speaker 1: So it's only seeing red right because.
• 14:42
  Speaker 2: Of the red filter, it only captured the red light
• 14:45
  Speaker 2: in the room, recording it as a black and white
• 14:47
  Speaker 2: image of red intensity.
• 14:48
  Speaker 1: It broadcasts that frame, so it sends a black and
• 14:50
  Speaker 1: white image of just the red stuff.
• 14:52
  Speaker 2: Then the camera wheel spins. Now the green filter is
• 14:54
  Speaker 2: over the lens. It captures a frame of the green light,
• 14:57
  Speaker 2: broadcasts that. The wheel spins again, blue filter broadcasts the
• 15:01
  Speaker 2: blue frame. The television receiver in your living room picks
• 15:05
  Speaker 2: up these frames, and its internal electric motor spins its
• 15:08
  Speaker 2: own color wheel in perfect synchronization with the camera.
• 15:12
  Speaker 1: So wait, when the TV screen displays the black and
• 15:14
  Speaker 1: white image of all the red information, the red slice
• 15:17
  Speaker 1: of the plastic wheel is physically passing in front of
• 15:20
  Speaker 1: the screen at that exact millisecond. I got you look
• 15:24
  Speaker 1: through the red plastic and the image looks red. A
• 15:27
  Speaker 1: fraction of a second later, the screen displays the green info,
• 15:30
  Speaker 1: and the green plastic spins in front of your eyes,
• 15:33
  Speaker 1: then the.
• 15:34
  Speaker 2: Blue, and because it's spinning at high speed, your brain's
• 15:37
  Speaker 2: persistence of vision kicks in again. You don't see distinct
• 15:40
  Speaker 2: flashes of red, green, and blue. Your brain blends the
• 15:44
  Speaker 2: three rapid sequential flashes together into a full color moving picture.
• 15:48
  Speaker 1: That is just It's basically a high speed, high tech flipbook.
• 15:52
  Speaker 2: That's exactly what it is.
• 15:53
  Speaker 1: From a pure physics standpoint, I can see how that works.
• 15:55
  Speaker 1: But from a consumer safety and practicality standpoint, this sounds
• 15:58
  Speaker 1: like an absolute nightmare.
• 16:00
  Speaker 2: The flaws were glaring and numerous. First and foremost, you're
• 16:05
  Speaker 2: dealing with a heavy physical moving part. It was loud
• 16:09
  Speaker 2: up early prototypes literally word vibrated and clattered in the
• 16:13
  Speaker 2: living room. It sounded like you had a large desk
• 16:16
  Speaker 2: fan running inside your television cabinet at all times.
• 16:20
  Speaker 1: That would drive me insane. And what about the size.
• 16:23
  Speaker 1: If the TV screen is square or rectangular and the
• 16:26
  Speaker 1: wheel is circular, the wheel has to be much much
• 16:29
  Speaker 1: larger than the screen just to cover the corners.
• 16:31
  Speaker 2: Right, That was the fatal physical limitation. To completely cover
• 16:35
  Speaker 2: the rectangular screen with one filter segment at a time,
• 16:38
  Speaker 2: the circular wheel had to be more than twice the
• 16:40
  Speaker 2: diameter of the screen itself.
• 16:41
  Speaker 1: Okay, let me be the mat on that. Yeah. By
• 16:43
  Speaker 1: nineteen fifty, people were buying large black and white sets,
• 16:46
  Speaker 1: maybe fifteen or twenty inches diagonally. If you wanted a
• 16:49
  Speaker 1: twenty inch color TV using the CBS system, the wheel inside.
• 16:54
  Speaker 2: Would have to be what four feet across over forty
• 16:56
  Speaker 2: inches in diameter. Yet, well, yeah, you would have a
• 16:58
  Speaker 2: heavy plastic and glass disc the size of a large
• 17:01
  Speaker 2: bicycle tire or a tractor wheel spinning at over one
• 17:04
  Speaker 2: thousand revolutions per minute inside your living room furniture.
• 17:07
  Speaker 1: That is terrifying. A wheel that big, spinning that fast
• 17:11
  Speaker 1: is basically a giant centrifuge.
• 17:13
  Speaker 2: It becomes a massive gyroscope. If you tried to physically
• 17:17
  Speaker 2: turn or move the TV while it was on, the
• 17:19
  Speaker 2: gyroscopic forces of the spinning wheel would fight.
• 17:22
  Speaker 1: Against you because it wants to stay upright.
• 17:24
  Speaker 2: Exactly, potentially shattering the wheel or ripping the motor right
• 17:27
  Speaker 2: out of its mountings. And if a piece of plastic
• 17:31
  Speaker 2: that large shattered while spinning.
• 17:32
  Speaker 1: At high speed deck like a buzzsaw.
• 17:34
  Speaker 2: Yeah, sending shrapnel right through the wooden cabinet. Because of
• 17:38
  Speaker 2: this massive physical danger, CBS was essentially forced to limit
• 17:43
  Speaker 2: their color TV screen sizes to about twelve point five inches.
• 17:47
  Speaker 2: You physically couldn't make them bigger safely.
• 17:50
  Speaker 1: So while your neighbor is watching a beautiful twenty inch
• 17:53
  Speaker 1: black and white TV, you are squinting at a tiny
• 17:57
  Speaker 1: twelve inch screen with a roaring motor onunderneath.
• 18:00
  Speaker 2: It not a great selling point.
• 18:01
  Speaker 1: What about the picture quality itself? Was it at least
• 18:04
  Speaker 1: bright and clear?
• 18:05
  Speaker 2: No, it was actually quite dim. Think about the physics
• 18:07
  Speaker 2: of a filter. A red filter works by blocking green
• 18:10
  Speaker 2: and blue light. A green filter blocks red and blue.
• 18:13
  Speaker 2: That means, at any given millisecond, the filter wheel is
• 18:15
  Speaker 2: physically blocking two thirds of the light coming from the
• 18:18
  Speaker 2: glowing phosphors screen. You are losing an immense amount of brightness.
• 18:22
  Speaker 1: So it's super dark.
• 18:24
  Speaker 2: Viewers had to watch CBS color programs in near total
• 18:27
  Speaker 2: darkness just to make out the image.
• 18:29
  Speaker 1: Okay, so it's small, it's noisy, and it's dim, but
• 18:33
  Speaker 1: surely the motion was smooth. I mean they figured out
• 18:35
  Speaker 1: that thirty frames. A second thing, well.
• 18:37
  Speaker 2: That introduces the mathematical problem. Remember the NTSC black and
• 18:41
  Speaker 2: white standard thirty frames a second. Yeah, CBS realized quickly
• 18:45
  Speaker 2: that if they flashed red, green, and blue at that speed,
• 18:48
  Speaker 2: the viewer would perceive a terrible headache inducing color flicker.
• 18:53
  Speaker 2: The eye would notice the gap between the red flash
• 18:55
  Speaker 2: and the next red flash because.
• 18:57
  Speaker 1: It has to wait for green and blue to take
• 18:58
  Speaker 1: their turns exactly.
• 19:00
  Speaker 2: To eliminate the flicker, CBS had to spin the wheel
• 19:03
  Speaker 2: much faster. They decided to run the color fields at
• 19:05
  Speaker 2: one hundred and forty four times a second.
• 19:07
  Speaker 1: Wow, that's fast.
• 19:08
  Speaker 2: But remember our invisible typewriter, the electron beam drawing the
• 19:12
  Speaker 2: raster scan. It has a physical speed limit. It cannot
• 19:15
  Speaker 2: draw infinite lines. If you force the beam to draw
• 19:18
  Speaker 2: one hundred and forty four pictures a second instead of
• 19:21
  Speaker 2: sixty half pictures, it doesn't have time to draw five
• 19:24
  Speaker 2: hundred and twenty five lines. It just can't physically sweep
• 19:27
  Speaker 2: back and forth that fast.
• 19:28
  Speaker 1: Ah. So to make the color wheel fast enough so
• 19:31
  Speaker 1: it doesn't cause a seizure, they have to sacrifice the
• 19:33
  Speaker 1: resolution of the image.
• 19:34
  Speaker 2: They had to drop the resolution down to four hundred and.
• 19:37
  Speaker 1: Five lines, which ruins the entire log and key compatibility.
• 19:41
  Speaker 2: Precisely, this was the ultimate fatal flaw of the CBS system.
• 19:45
  Speaker 2: The Federal Communications Commission the FCC, which regulates all radio
• 19:50
  Speaker 2: and television broadcasting in the US, used a lock and
• 19:52
  Speaker 2: key analogy.
• 19:53
  Speaker 1: Okay, laid on me.
• 19:54
  Speaker 2: The transmitter on the broadcast tower is the key. The
• 19:56
  Speaker 2: television receiver in your living room is the lock. Because
• 20:00
  Speaker 2: as the CBS system used a completely different mathematical language,
• 20:03
  Speaker 2: four hundred and five lines instead of five to twenty five,
• 20:05
  Speaker 2: and one hundred and forty four fields a second instead
• 20:07
  Speaker 2: of sixty, and existing black and white TV simply could
• 20:11
  Speaker 2: not understand the CBS signal.
• 20:13
  Speaker 1: It wouldn't just show the program in black and white
• 20:15
  Speaker 1: like it wouldn't just ignore the color.
• 20:16
  Speaker 2: No, the horizontal and vertical sink pulses would be entirely mismatched.
• 20:22
  Speaker 2: If the CBS color program came on, the fifteen million
• 20:25
  Speaker 2: expensive black and white TVs sitting in homes across America
• 20:29
  Speaker 2: would completely lose their minds, so would happen The screen
• 20:32
  Speaker 2: would dissolve into rolling, tearing incomprehensible static, or just go
• 20:37
  Speaker 2: totally blank.
• 20:38
  Speaker 1: So the existing TVs were rendered obsolete. Overnight. You couldn't
• 20:42
  Speaker 1: watch the new broadcasts unless you went out and bought
• 20:44
  Speaker 1: a separate, expensive mechanical spinning wheel adapter to bolt onto your.
• 20:49
  Speaker 2: Set, and that adapter would still require you to shrink
• 20:52
  Speaker 2: your screen size. It was a logistical nightmare knowing.
• 20:55
  Speaker 1: All of this, the noise, the size limits, the dimness,
• 20:58
  Speaker 1: the absolute destruction of compatibility. I would assume the SEC
• 21:01
  Speaker 1: just laughed CBS out of the room.
• 21:02
  Speaker 2: You would assume that, But the truth is, a glaring
• 21:05
  Speaker 2: technological flaw doesn't always stop a stubborn corporation or a
• 21:08
  Speaker 2: confused government agency. This brings us out of the engineering
• 21:12
  Speaker 2: labyn into the boardroom. The color War of the early
• 21:15
  Speaker 2: nineteen fifties is one of the most brutal corporate battles
• 21:18
  Speaker 2: in tech history.
• 21:19
  Speaker 1: The paperwork we've looked at regarding the FCC hearings is
• 21:22
  Speaker 1: just staggering. What actually happened when CBS presented this mechanical
• 21:27
  Speaker 1: monster well.
• 21:29
  Speaker 2: In October nineteen fifty, despite every mechanical flaw we just discussed,
• 21:32
  Speaker 2: the Federal Communications Commission officially approved the CBS spinning wheel
• 21:36
  Speaker 2: system as the sole official color television standard for the
• 21:40
  Speaker 2: United States.
• 21:42
  Speaker 1: That is a shocking decision. I am genuinely struggling to
• 21:45
  Speaker 1: understand how a panel of government regulators and engineers could
• 21:49
  Speaker 1: look at a massive, spinning plastic wheel that breaks every
• 21:53
  Speaker 1: TV in America and say, yes, this is the future.
• 21:56
  Speaker 2: They felt their hands were tied to understand the FCC's logic.
• 22:00
  Speaker 2: To look at the competition, the FCC had been holding
• 22:02
  Speaker 2: hearings for months looking at proposals from other companies, primarily RCA,
• 22:06
  Speaker 2: the Radio Corporation of America.
• 22:08
  Speaker 1: They're huge, right.
• 22:09
  Speaker 2: RCA was the giant of the industry. They owned the
• 22:12
  Speaker 2: NBC network, They manufactured the cameras, they manufactured the TVs.
• 22:15
  Speaker 2: And RCA promised an all electronic color system, no moving parts,
• 22:19
  Speaker 2: a system that would be perfectly compatible with existing black
• 22:23
  Speaker 2: and white sets.
• 22:23
  Speaker 1: Which sounds like exactly what the world needed. So why
• 22:26
  Speaker 1: didn't the FCC choose RCA.
• 22:29
  Speaker 2: Because RCA's early prototypes in nineteen forty nine and nineteen
• 22:32
  Speaker 2: fifty were absolutely terrible, how terrible, comically bad. The electronics
• 22:37
  Speaker 2: required to process color signals were so complex that RCA
• 22:41
  Speaker 2: couldn't fit them into a normal cabinet. Their prototype receivers
• 22:44
  Speaker 2: were the size of refrigerators. A refrigerator TV packed with
• 22:48
  Speaker 2: dozens of extra vacuum tubes that overheated constantly, and the
• 22:51
  Speaker 2: picture quality was abysmal. The colors drifted constantly, flesh tones
• 22:55
  Speaker 2: looked green or purple, the image was fuzzy gross. In
• 22:59
  Speaker 2: comparative demonstrations, the CBS spinning wheel, for all its clunkiness,
• 23:02
  Speaker 2: produced a beautifully vibrant, sharp, reliable color picture. The RCA
• 23:07
  Speaker 2: electronic system looked like a blurry neon mess ah.
• 23:11
  Speaker 1: So the FCC was faced with a choice a mechanical
• 23:13
  Speaker 1: system that works perfectly right now but breaks compatibility, versus
• 23:17
  Speaker 1: an electronic system that preserves compatibility but looks awful. It
• 23:20
  Speaker 1: might take a decade to figure.
• 23:21
  Speaker 2: Out exactly, and the FCC commissioners decided they couldn't wait.
• 23:26
  Speaker 2: They believed the public wanted color immediately. They stated that
• 23:29
  Speaker 2: the CBS picture was vastly superior in fidelity, and they
• 23:32
  Speaker 2: pulled the trigger. They made CBS the law of the LAMB.
• 23:36
  Speaker 1: I can only imagine the absolute outrage from RCA and
• 23:39
  Speaker 1: the rest of the industry. You've got companies pumping out
• 23:42
  Speaker 1: thousands of black and white TVs a day, and the
• 23:45
  Speaker 1: government just told the public those TVs are about to
• 23:47
  Speaker 1: be useless.
• 23:48
  Speaker 2: The backlash was instantaneous and massive. David Sarnoff, the powerful
• 23:53
  Speaker 2: chairman of RCA, was furious. He was a visionary who
• 23:56
  Speaker 2: had practically built the broadcasting industry, and he viewed mechanical
• 24:00
  Speaker 2: wheel as a step backer into the stone age. Rightly so, honestly,
• 24:04
  Speaker 2: he publicly lambasted the FCC, calling the CBS system scientifically unsound,
• 24:09
  Speaker 2: in a complete absurdity.
• 24:11
  Speaker 1: It wasn't just corporate pride either. The economic impact must
• 24:14
  Speaker 1: have been devastating.
• 24:15
  Speaker 2: It caused an immediate retail panic. Think about a family
• 24:19
  Speaker 2: in November nineteen fifty who had been saving up to
• 24:21
  Speaker 2: buy a television for Christmas. They read in the newspaper
• 24:24
  Speaker 2: that the FCC just approved a new color standard that
• 24:27
  Speaker 2: won't work on the TVs in the store. What do
• 24:29
  Speaker 2: they do?
• 24:30
  Speaker 1: They stopped buying. Nobody is going to drop thousands of
• 24:33
  Speaker 1: dollars on a machine if the channels are going to
• 24:36
  Speaker 1: turn to static next.
• 24:37
  Speaker 2: Month exactly, Television sales plummeted practically overnight. Warehouses were filling
• 24:42
  Speaker 2: up with unsold black and white inventory. Retail store owners
• 24:46
  Speaker 2: were screaming at manufactures. The entire billion dollar industry hit
• 24:51
  Speaker 2: a brick wall.
• 24:52
  Speaker 1: Jikes.
• 24:53
  Speaker 2: RCI realized they couldn't just write angry letters to the FCC.
• 24:56
  Speaker 2: They had to stop the rollout of the CBS system
• 24:58
  Speaker 2: by any means necessary.
• 25:00
  Speaker 1: So they took it to court.
• 25:01
  Speaker 2: They filed a massive federal lawsuit. RCA, joined by other
• 25:05
  Speaker 2: major electronics manufacturers and even powerful electrical workers' unions who
• 25:09
  Speaker 2: feared massive job losses, sued the United States government and
• 25:13
  Speaker 2: the FCC in a federal court in.
• 25:15
  Speaker 1: Chicago, a huge coalition.
• 25:17
  Speaker 2: Their argument was that the FCC was acting arbitrarily and capriciously.
• 25:21
  Speaker 2: They argued that FCC was stifling electronic innovation and essentially
• 25:24
  Speaker 2: destroying a massive American industry by forcing an incompatible, flawed
• 25:29
  Speaker 2: mechanical standard on the public.
• 25:30
  Speaker 1: The audacity of suing the federal government over television standards,
• 25:34
  Speaker 1: and from the legal history, this didn't just stay in
• 25:37
  Speaker 1: a lower court.
• 25:38
  Speaker 2: No, the stakes were too high. The case was expedited
• 25:42
  Speaker 2: and went all the way to the top the Supreme
• 25:44
  Speaker 2: Court if the United States heard the arguments. Wow, And
• 25:48
  Speaker 2: in May nineteen fifty one, the Supreme Court handed down
• 25:51
  Speaker 2: its decision.
• 25:52
  Speaker 1: And did the Supreme Court strike down the mechanical wheel?
• 25:56
  Speaker 2: Surprisingly? No, The Supreme Court ruled in favor of the FCCS.
• 26:00
  Speaker 1: Wait, really on what grounds?
• 26:02
  Speaker 2: The Court wasn't ruling on which technology was scientifically better,
• 26:06
  Speaker 2: they were ruling on administrative law. The justices stated that
• 26:10
  Speaker 2: the SEC had been granted the legal authority by Congress
• 26:13
  Speaker 2: to set bardcasting standards, and that they had acted properly
• 26:16
  Speaker 2: based on the evidence presented to them at the time.
• 26:18
  Speaker 2: Ah I say, since RCA's prototypes were demonstrably poor, the
• 26:23
  Speaker 2: FCC was within its rights to choose CBS. CBS had
• 26:26
  Speaker 2: won the ultimate legal victory. They had the green light
• 26:29
  Speaker 2: to roll out their mechanical color wheels across the entire nation.
• 26:33
  Speaker 1: But history tells us they didn't. I mean, we don't
• 26:35
  Speaker 1: have spinning wheels in our TVs today. If CBS won
• 26:38
  Speaker 1: the Supreme Court case, what stopped them from blanketing the
• 26:40
  Speaker 1: country with mechanical TVs?
• 26:42
  Speaker 2: Fate, global geopolitics and an unlikely savior, which was the
• 26:46
  Speaker 2: Korean War.
• 26:47
  Speaker 1: Let's explore that because it's a fascinating twist. How does
• 26:50
  Speaker 1: a war halfway across the world stop a TV rollout?
• 26:54
  Speaker 2: Well, just a few months after the Supreme Court victory,
• 26:56
  Speaker 2: in the summer of nineteen fifty one, CBS official started
• 27:00
  Speaker 2: broadcasting in color, but almost nobody was watching.
• 27:04
  Speaker 1: Why not.
• 27:04
  Speaker 2: Manufacturers had refused to build the mechanical sets so consumers
• 27:07
  Speaker 2: couldn't buy them. There were maybe a few dozen prototypes
• 27:11
  Speaker 2: CBS color sets and existence, and of course the fifteen
• 27:15
  Speaker 2: million standard TVs just saw rolling static. CBS was bleeding
• 27:19
  Speaker 2: money trying to produce color content for an audience of zero.
• 27:22
  Speaker 1: They won the battle, but were losing the war, and.
• 27:24
  Speaker 2: Then the actual war intervened. In October nineteen fifty one,
• 27:27
  Speaker 2: the US government's Office of Defense Mobilization stepped in with
• 27:31
  Speaker 2: a sweeping emergency order. They completely legally banned the production
• 27:35
  Speaker 2: of color televisions for the general public.
• 27:37
  Speaker 1: A total ban. Why target color TVs specifically because.
• 27:41
  Speaker 2: Building these new complex color systems, especially the heavily motorized
• 27:45
  Speaker 2: CBS sets and the massive experimental RCA electronic tubes, required
• 27:50
  Speaker 2: vast amounts of vital strategic materials like what Specifically, they
• 27:54
  Speaker 2: needed enormous amounts of copper for the heavy deflection yokes,
• 27:57
  Speaker 2: cobalt for magnets, aluminium, and highly specific electronic components like
• 28:01
  Speaker 2: specialized vacuum tubes. The military desperately needed those exact same
• 28:06
  Speaker 2: materials for radar rays, radio communications, and jet aircraft for
• 28:09
  Speaker 2: the war effort in Korea. Wow, the government deemed color
• 28:13
  Speaker 2: TV a non essential luxury and halted all commercial production
• 28:17
  Speaker 2: to conserve resources.
• 28:19
  Speaker 1: The irony here is absolutely delicious. A massive geopolitical conflict
• 28:24
  Speaker 1: accidentally saved the American consumer from being permanently stuck with
• 28:28
  Speaker 1: a clunky, noisy, mechanical, incompatible television system. It gave the
• 28:32
  Speaker 1: government an excuse to hit the pause button.
• 28:34
  Speaker 2: It forced CBS to stop manufacturing their spinning wheels, halting
• 28:38
  Speaker 2: their momentum entirely. But crucially, while commercial manufacturing was banned,
• 28:43
  Speaker 2: laboratory research was not.
• 28:44
  Speaker 1: Oh a sneaky.
• 28:45
  Speaker 2: The pause gave the rival engineers at RCA and a
• 28:48
  Speaker 2: consortium of other tech companies the one thing they desperately
• 28:51
  Speaker 2: needed time time.
• 28:52
  Speaker 1: To figure out how to do it right. Speaking of
• 28:55
  Speaker 1: taking a pause, if you're hooked on this story, give
• 28:57
  Speaker 1: kirskasog podcast field to five star rating. Okay, back to
• 29:01
  Speaker 1: the lab. In the world of technology, a few years
• 29:05
  Speaker 1: in a lab can change everything, which brings us to
• 29:09
  Speaker 1: the ultimate engineering challenge. Let's put ourselves in the shoes
• 29:12
  Speaker 1: of those RCAA engineers in nineteen fifty one. You've been
• 29:15
  Speaker 1: given a stay of execution, the mechanical wheel is paused.
• 29:19
  Speaker 1: Now you have to deliver on your promise.
• 29:21
  Speaker 2: And the promise was a seemingly impossible paradox, right, Think about.
• 29:26
  Speaker 1: The constraints here. If you're keeping track Constraint one moving parts,
• 29:30
  Speaker 1: no spitting wheels. Constraint two absolute lock and key compatibility,
• 29:35
  Speaker 1: you absolutely cannot break the fifteen million black and white
• 29:39
  Speaker 1: TVs already sitting in living rooms. When a color signal
• 29:42
  Speaker 1: goes out, the old TVs have to display a perfect
• 29:45
  Speaker 1: black and white picture.
• 29:45
  Speaker 2: That was no negotiable.
• 29:46
  Speaker 1: Constrain three the physics of radio waste.
• 29:48
  Speaker 2: That was the tightest constraint of all the sec heavily
• 29:51
  Speaker 2: regulates the radio spectrum. They allocate a specific lane on
• 29:54
  Speaker 2: the radio highway for each TV channel. That lane is
• 29:57
  Speaker 2: exactly six megahertz wide.
• 29:59
  Speaker 1: Okay, six megaher.
• 30:00
  Speaker 2: The original nineteen forty one black and white TV signal
• 30:03
  Speaker 2: was designed to take up almost that entire six megahertz
• 30:06
  Speaker 2: lane just to send the brightness and audio information.
• 30:09
  Speaker 1: So, to summarize the problem for our listeners, you have
• 30:12
  Speaker 1: to send three times as much visual information. You need red, green,
• 30:16
  Speaker 1: and blue data, and you have to cram it into
• 30:19
  Speaker 1: the exact same six megahertz lane that is already completely
• 30:23
  Speaker 1: full of black and white data without the black and
• 30:26
  Speaker 1: white TV noticing that the new data is even there.
• 30:29
  Speaker 2: Sounds impossible, right, How do.
• 30:30
  Speaker 1: You cram a full color image into the exact same
• 30:34
  Speaker 1: invisible radio wave.
• 30:35
  Speaker 2: That was the challenge taken up by the second National
• 30:38
  Speaker 2: Television System Committee, the NTSC, which reformed to solve this
• 30:46
  Speaker 2: exact mess. It included engineers from RCA, Philco, Hazeltyan and others,
• 30:50
  Speaker 2: and their solution was one of the most elegant, brilliant
• 30:53
  Speaker 2: electronic compromises in the history of telecommunications.
• 30:56
  Speaker 1: Let's break down this mathematical magic. How do they do it?
• 30:59
  Speaker 2: The first stroke genius was realizing they didn't actually need
• 31:02
  Speaker 2: to broadcast three separate full resolution pictures of red, green,
• 31:06
  Speaker 2: and blue. They realized they had to separate the concept
• 31:10
  Speaker 2: of video into two completely different properties, luminance and prominance.
• 31:15
  Speaker 1: Luminance and prominance, what do those mean? In practical terms?
• 31:18
  Speaker 2: Luminance is simply the brightness of the image. It is
• 31:20
  Speaker 2: the black, the white, the grays, the sharp edges, the
• 31:23
  Speaker 2: fine detail, and the contrast. Okay, prominance is purely the
• 31:27
  Speaker 2: color information, the specific hue like is it red or green?
• 31:31
  Speaker 2: And the saturation is it deep red or pale pink?
• 31:34
  Speaker 1: Okay, consider this analogy. Think of the television signal like
• 31:38
  Speaker 1: a page in a high quality child's coloring book. The
• 31:41
  Speaker 1: luminance signal is the crisp black ink outlines printed on
• 31:44
  Speaker 1: the page. He shows all the fine detail, the shapes
• 31:47
  Speaker 1: of the trees, the shading on a face.
• 31:49
  Speaker 2: That's a good way to picture it.
• 31:50
  Speaker 1: Now, the old black and white TVs sitting in millions
• 31:52
  Speaker 1: of homes, they only look for black ink. They receive
• 31:55
  Speaker 1: the NTSC signal, read the luminance data, draw the black
• 31:58
  Speaker 1: and white picture, and completely ignore everything else. Everyone with
• 32:02
  Speaker 1: an old TV is perfectly happy. Compatibility Salt.
• 32:04
  Speaker 2: It is a perfect analogy. The old TV doesn't even
• 32:07
  Speaker 2: have the circuitry to recognize that color information exists, right,
• 32:11
  Speaker 2: But a new, expensive color TV it receives that exact
• 32:15
  Speaker 2: same coloring book page. But it also receives a secret,
• 32:19
  Speaker 2: mathematically encoded box of crayons, the prominence signal. It draws
• 32:25
  Speaker 2: the crisp black lines of the luminance signal, and then
• 32:28
  Speaker 2: it decodes the crominince signal to know exactly where to
• 32:30
  Speaker 2: scribble the crayons to fill in the colors inside those lines.
• 32:34
  Speaker 1: But here's where I want to push back. If you
• 32:36
  Speaker 1: are adding a whole box of crayons to the signal,
• 32:38
  Speaker 1: that's still extra data. How does that fit into the
• 32:41
  Speaker 1: six MEGAHERTZT lane if the black ink is already taking
• 32:44
  Speaker 1: up all the room.
• 32:44
  Speaker 2: Because of a fascinating biological loophole.
• 32:47
  Speaker 1: Biology again, yep.
• 32:48
  Speaker 2: The NTSC engineers studied human vision, specifically the rods and
• 32:52
  Speaker 2: cones in our retinas. They discovered that the human eye
• 32:55
  Speaker 2: is incredibly sensitive to changes in brightness luminance, which is
• 32:59
  Speaker 2: how we perceive sharp edges and find details. We have
• 33:02
  Speaker 2: millions of rod cells dedicated to this. Okay, but our
• 33:05
  Speaker 2: eyes are actually quite terrible at perceiving fine detail in
• 33:08
  Speaker 2: pure color prominence.
• 33:09
  Speaker 1: Wait, really, we don't see color and high resolution we don't.
• 33:13
  Speaker 2: If I show you a high resolution black and white
• 33:15
  Speaker 2: photo and then vaguely wash some low resolution blurry water
• 33:20
  Speaker 2: colors over it, your brain will combine the sharp black
• 33:23
  Speaker 2: edges with the blurry color and perceive a sharp, full
• 33:27
  Speaker 2: color image.
• 33:28
  Speaker 1: That's amazing.
• 33:28
  Speaker 2: The NTSC engineers realized they didn't need to send high
• 33:31
  Speaker 2: definition color. They could severely compress the prominence signal, making
• 33:35
  Speaker 2: it a very blurry box of crans, taking up vastly
• 33:38
  Speaker 2: less data than a full picture would.
• 33:40
  Speaker 1: That is brilliant you trick the human eye. But even
• 33:43
  Speaker 1: a compressed blurry box of crayons takes up some room
• 33:46
  Speaker 1: on the radio wave. Where did they physically hide this
• 33:48
  Speaker 1: color data in the six megahertz lane?
• 33:51
  Speaker 2: This is where we dive into the real physics the
• 33:53
  Speaker 2: subcarrier Magic An RCA engineer named Alda Bedford, building on
• 33:57
  Speaker 2: work from others, made a startling mathematical discovery.
• 34:00
  Speaker 1: What did you find.
• 34:01
  Speaker 2: When you look at the radio frequency spectrum of a
• 34:04
  Speaker 2: black and white TV signal using Fouria analysis? The energy
• 34:08
  Speaker 2: isn't a solid block Because the TV picture is scanned
• 34:11
  Speaker 2: in horizontal lines at specific intervals, the radio energy clusters
• 34:15
  Speaker 2: around specific frequencies, leaving tiny microscopic gaps of completely empty
• 34:20
  Speaker 2: space in between. It looks like the teeth of a comb.
• 34:22
  Speaker 1: So there were tiny slivers of empty radio wave just
• 34:25
  Speaker 1: sitting there, completely unused, between the lines of the black
• 34:29
  Speaker 1: and white data.
• 34:30
  Speaker 2: Exactly the NTSC engineers decided to hide the compressed prominence
• 34:34
  Speaker 2: signal the color data inside those microscopic gaps. They created
• 34:38
  Speaker 2: a new, highly precise mathematical frequency called the color subcarrier. Specifically,
• 34:44
  Speaker 2: they set it at three point five seven nine five
• 34:46
  Speaker 2: four five megahertz.
• 34:48
  Speaker 1: That is a very specific number.
• 34:49
  Speaker 2: It had to be. By broadcasting the color data precisely
• 34:52
  Speaker 2: at this frequency, the peaks of the color wave perfectly
• 34:54
  Speaker 2: aligned with the valleys of the black and white wave.
• 34:56
  Speaker 2: The two signals occupied the exact same six megaherts lane,
• 35:00
  Speaker 2: but they interleaved. Oh see, they fit together like the
• 35:03
  Speaker 2: teeth of two combs sliding into each other without touching.
• 35:06
  Speaker 1: So the color data is just squeezed into the cracks
• 35:08
  Speaker 1: of the existing radio wave. That is unbelievable.
• 35:11
  Speaker 2: It was an absolute triumph of mathematics. However, doing this
• 35:14
  Speaker 2: caused one tiny unforeseen problem.
• 35:17
  Speaker 1: Of course it did.
• 35:18
  Speaker 2: The new color subcarrier frequency was so close to the
• 35:21
  Speaker 2: audio frequency of the broadcast that they started to interact.
• 35:24
  Speaker 2: They created an interference beat, a low, annoying buzzing sound
• 35:29
  Speaker 2: in the audio track of the television.
• 35:31
  Speaker 1: Physics always demands a trade off. You solve the visual problem,
• 35:35
  Speaker 1: you ruin the audio. How did they fix the.
• 35:37
  Speaker 2: Buzzing to make the math work To ensure the color
• 35:40
  Speaker 2: teeth didn't scrape against the audio teeth. They had to
• 35:43
  Speaker 2: alter the fundamental timing of the entire system by a
• 35:46
  Speaker 2: microscopic fraction. Remember our invisible typewriter drawing thirty frames a second.
• 35:51
  Speaker 1: Yes, sync to the sixty hertz power grid.
• 35:53
  Speaker 2: They had to slow it down just a hair. Instead
• 35:56
  Speaker 2: of broadcasting at exactly thirty frames per second, they slowed
• 35:59
  Speaker 2: the entire rasters scand down by one tenth of one percent.
• 36:03
  Speaker 2: They changed the national standard from thirty point zero zero
• 36:06
  Speaker 2: zero frames per second to twenty nine point nine seven frames.
• 36:09
  Speaker 1: Per second twenty nine point nine seven frames per second,
• 36:13
  Speaker 1: and that tiny, imperceptible slowdown shifted the math just enough
• 36:17
  Speaker 1: to hide the color in the gaps and eliminate the
• 36:19
  Speaker 1: audio buzz.
• 36:20
  Speaker 2: It did, and it was a compromise so vanishingly small
• 36:23
  Speaker 2: that the human eye couldn't perceive it. More importantly, the
• 36:27
  Speaker 2: millions of existing black and white televisions couldn't notice the
• 36:29
  Speaker 2: difference either.
• 36:30
  Speaker 1: Oh so they didn't break.
• 36:32
  Speaker 2: No, Their internal vacuum tube electronics just naturally drifted and
• 36:35
  Speaker 2: locked onto the slightly slower twenty nine point nine to
• 36:39
  Speaker 2: seven speed without missing a single beat. The picture stayed
• 36:42
  Speaker 2: perfectly stable.
• 36:43
  Speaker 1: That is, one of the greatest engineering victories of the
• 36:45
  Speaker 1: twentieth century. You've completely solved the lock and key.
• 36:48
  Speaker 2: Problem, and the government recognized it. In December nineteen fifty three,
• 36:52
  Speaker 2: the FCC looked at this new, fully compatible, incredibly elegant,
• 36:57
  Speaker 2: all electronic NTSC standard, they realized their earlier blunder with
• 37:01
  Speaker 2: the CBS mechanical wheel, reversed their nineteen fifty decision and
• 37:05
  Speaker 2: officially adopted the NTSC standard for all color broadcasting in
• 37:09
  Speaker 2: the United States.
• 37:10
  Speaker 1: The war the radio waves is over, but from our
• 37:12
  Speaker 1: dive into this, I know that figuring out the invisible
• 37:15
  Speaker 1: math in the air was only half the battle. Now,
• 37:17
  Speaker 1: RCA and the manufacturers actually had to physically build a
• 37:20
  Speaker 1: glass box for the living room that could catch that
• 37:23
  Speaker 1: signal and shoot three different colors of light at once
• 37:26
  Speaker 1: without the mixing into a giant, muddy brown mess.
• 37:29
  Speaker 2: That is where the elegance of mathematics slams hard into
• 37:32
  Speaker 2: the brutal reality of nineteen fifty's physical manufacturing. The radio
• 37:37
  Speaker 2: wave was a masterpiece. The color television set itself was
• 37:41
  Speaker 2: a heavy, inefficient, brute force hardware miracle. To display the
• 37:46
  Speaker 2: NTSC signal, engineers had to completely reinvent the inside of
• 37:50
  Speaker 2: the cathode ray tube.
• 37:51
  Speaker 1: Let's walk through that redesign. Earlier, we established that a
• 37:55
  Speaker 1: black and white tube has one single electron gun shooting
• 37:59
  Speaker 1: at a solid union form sheet of white phosphor. How
• 38:02
  Speaker 1: does a color tube change that architecture.
• 38:04
  Speaker 2: It multiplies the complexity exponentially. Instead of one electron gun
• 38:08
  Speaker 2: in the neck of the tube, a color CRT has
• 38:10
  Speaker 2: three distinct electron guns bundled together.
• 38:13
  Speaker 1: Three guns.
• 38:14
  Speaker 2: One gun is electronically wired to respond only to the
• 38:16
  Speaker 2: red prominent signal, one responds only to the green, and
• 38:19
  Speaker 2: one responds to the blue.
• 38:20
  Speaker 1: Okay, three guns firing simultaneously. What are they shooting at?
• 38:23
  Speaker 2: The screen is no longer a smooth uniform coating. The
• 38:27
  Speaker 2: inside of the front glass is now meticulously covered in
• 38:30
  Speaker 2: hundreds of thousands of microscopic individual phosphor dots. And they
• 38:34
  Speaker 2: aren't randomly placed. They are arranged in incredibly precise tiny
• 38:39
  Speaker 2: clusters of three, one red emitting phosphoronot, one green, one blue.
• 38:44
  Speaker 2: These tiny triangular clusters are called triads triads.
• 38:48
  Speaker 1: So you have a red gun, a green gun, and
• 38:50
  Speaker 1: a blue gun firing at hundreds of thousands of microscopic red, green,
• 38:53
  Speaker 1: and blue dots. Correct. But if I fire a spray
• 38:56
  Speaker 1: of electrons from the back of a tube, how do
• 38:58
  Speaker 1: I make absolutely sure that the beam from the red
• 39:01
  Speaker 1: gun only hits the red dots and doesn't accidentally splash
• 39:05
  Speaker 1: over onto the green and blue dots sitting a millimeter away.
• 39:08
  Speaker 2: That was the million dollar physical problem. If the electron
• 39:10
  Speaker 2: beam splashed or overlapped even slightly, the colors would bleed
• 39:13
  Speaker 2: together on the screen, red and green would mix, and
• 39:16
  Speaker 2: instead of a crisp bread apple, you'd get a muddy, yellow,
• 39:18
  Speaker 2: brown blob.
• 39:19
  Speaker 1: Nobody wants that.
• 39:20
  Speaker 2: The solution was based on a concept patented back in
• 39:23
  Speaker 2: nineteen thirty eight by a German inventor named Werner Flexig.
• 39:27
  Speaker 2: It is called the shadow mask.
• 39:28
  Speaker 1: The shadow mask. How does it work?
• 39:30
  Speaker 2: It is a physical object, a very thin sheet of metal,
• 39:34
  Speaker 2: usually steel or a specialized alloy called invar, placed directly
• 39:39
  Speaker 2: inside the vacuum tube, just about half an inch behind
• 39:41
  Speaker 2: the glass phosphor screen. And this metal sheet is completely perforated.
• 39:47
  Speaker 2: It is punched with hundreds of thousands of incredibly tiny, precise,
• 39:52
  Speaker 2: microscopic holes. There is exactly one hole in the metal
• 39:56
  Speaker 2: for every single triad of phosphor dots on the glass.
• 40:00
  Speaker 1: Okay, let's visualize this. Imagine you're trying to spray paint
• 40:03
  Speaker 1: a red dot, a blue dot, and a green dot
• 40:06
  Speaker 1: right next to each other on a brick wall, and
• 40:07
  Speaker 1: you're standing all the way across the room using three
• 40:10
  Speaker 1: different spray paint hoses.
• 40:11
  Speaker 2: That's a tough shot.
• 40:12
  Speaker 1: It's impossible to be that precise. The paint is going
• 40:15
  Speaker 1: to spread out, overlap and make a brown mess on
• 40:17
  Speaker 1: the wall. But consider the alternative. What if you take
• 40:20
  Speaker 1: a large piece of cardboard, poke a single tiny hole
• 40:23
  Speaker 1: in it, and hold it just one inch in front
• 40:25
  Speaker 1: of the wall. Right now, you spray from your three
• 40:27
  Speaker 1: different hoses across the room, but you physically separate the
• 40:30
  Speaker 1: hoses by a few feet. The three streams of paint
• 40:33
  Speaker 1: approach the cardboard from three slightly different angles. The cardboard
• 40:37
  Speaker 1: physically blocks all the messy, overlapping edges of the spray.
• 40:41
  Speaker 1: The paint only goes through that single tiny hole, and
• 40:44
  Speaker 1: because the hoses are angled differently, the red paint goes
• 40:47
  Speaker 1: through the hole and hits the left side of the brick.
• 40:49
  Speaker 1: The blue paint goes through on a straight angle and
• 40:51
  Speaker 1: hits the middle. The green paint comes from the right
• 40:54
  Speaker 1: and hits the right side the cardboard masks the shadow
• 40:58
  Speaker 1: of the spray.
• 40:59
  Speaker 2: That is a flowmollless analogy for the internal geometry of
• 41:02
  Speaker 2: a color CRT. The three electron guns are physically separated
• 41:06
  Speaker 2: at the back of the tube, clustered in a triangle. Therefore,
• 41:09
  Speaker 2: their beams travel across the vacuum and approach the shadow
• 41:13
  Speaker 2: mass from three slightly different angles.
• 41:15
  Speaker 1: Just like the hoses.
• 41:16
  Speaker 2: Exactly, the solid metal of the mass blocks the vast
• 41:19
  Speaker 2: majority of the wide electron beams. Only the electrons that
• 41:23
  Speaker 2: are perfectly aligned pass through the microscopic hole, and because
• 41:26
  Speaker 2: of their distinct approach angles, the electrons from the red
• 41:29
  Speaker 2: gun pass through the hole and land exclusively on the
• 41:31
  Speaker 2: red phosphor dot. The green gun beam passes through the
• 41:34
  Speaker 2: same hole, but lands exclusively on the green dot. The
• 41:37
  Speaker 2: geometry physically separates the colors.
• 41:40
  Speaker 1: Conceptually, it's a brilliant geometric trick. Yeah, but let's talk
• 41:44
  Speaker 1: about the manufacturing nightmare of actually building this. In nineteen
• 41:47
  Speaker 1: fifty three.
• 41:48
  Speaker 2: It was a huge headache.
• 41:49
  Speaker 1: You're talking about a massive sheet of metal with hundreds
• 41:53
  Speaker 1: of thousands of microscopic holes that have to align flawlessly
• 41:56
  Speaker 1: with hundreds of thousands of microscopic chemical dots on a
• 42:00
  Speaker 1: heavy curved piece of glass. How on earth did they
• 42:03
  Speaker 1: manufacture that before the invention of lasers or computer guided drills.
• 42:08
  Speaker 2: Well, they couldn't use physical drills. A drill bit that
• 42:10
  Speaker 2: small would snap instantly. They had to use chemistry. They
• 42:14
  Speaker 2: utilize a process called photochemical machining. It is incredibly tedious,
• 42:19
  Speaker 2: somewhat similar to developing a photograph or etching a modern microchip.
• 42:23
  Speaker 1: Walk us through the chemistry. How do you drill a
• 42:25
  Speaker 1: hole with light?
• 42:26
  Speaker 2: You start with a solid, thin sheet of invar steel.
• 42:29
  Speaker 2: You coat both sides of this metal completely in a
• 42:31
  Speaker 2: light sensitive chemical called a photoresist. Then you place a
• 42:34
  Speaker 2: master pattern, a glass photographic plate containing the images of
• 42:38
  Speaker 2: hundreds of thousands of black dots over the metal. You
• 42:41
  Speaker 2: expose the whole thing to intensely bright ultraviolet light.
• 42:44
  Speaker 1: The UV light hits the chemicals.
• 42:46
  Speaker 2: Where the UV light hits the photoresis, the chemical reacts
• 42:49
  Speaker 2: and hardens into an impenetrable plastic shell. But where the
• 42:52
  Speaker 2: black dots on the master plate cast a shadow, the
• 42:55
  Speaker 2: chemical remains soft. Then you wash the unhardened chemical away,
• 43:00
  Speaker 2: leaving bare metal where.
• 43:01
  Speaker 1: The hole should be, and then comes the acid.
• 43:03
  Speaker 2: Exactly, You submerge this entire sheet of metal into a
• 43:07
  Speaker 2: vat of highly corrosive liquid acid, usually ferric chloride. The
• 43:11
  Speaker 2: hardened footo resist protects the main body of the metal
• 43:14
  Speaker 2: that the acid eats right through the tiny, unprotected bare spots.
• 43:18
  Speaker 2: It literally dissolves the steel, etching out hundreds of thousands
• 43:22
  Speaker 2: of perfectly tapered microscopic holes.
• 43:25
  Speaker 1: Using vats of liquid acid to drill half a million holes.
• 43:28
  Speaker 1: That is hardcore nineteen fifties industrial engineering. Yeah, but that
• 43:32
  Speaker 1: only solves the metal mask. How do you make sure
• 43:34
  Speaker 1: the holes in the metal perfectly line up with the
• 43:36
  Speaker 1: chemical dots on the glass screen. If the mask is
• 43:39
  Speaker 1: off by even a millimeter, the TV is useless.
• 43:42
  Speaker 2: RCAA solved that with another stroke of brilliance. They didn't
• 43:45
  Speaker 2: try to manufacture the screen and the mask separately, and
• 43:47
  Speaker 2: hope they fit. They use the finished shadow mask itself
• 43:50
  Speaker 2: as the stencil to paint the screen.
• 43:52
  Speaker 1: Oh, they are a matched pair.
• 43:54
  Speaker 2: Yes. During assembly, they would place the freshly etched shadow
• 43:58
  Speaker 2: mask inside the bare glass tube. They would coat the
• 44:02
  Speaker 2: glass in a liquid slurry containing the red phosphor, which
• 44:05
  Speaker 2: was also mixed with a UV sensitive photoricist. Then they
• 44:09
  Speaker 2: would shine a powerful UV light through the holes in
• 44:11
  Speaker 2: the shadow mask from the exact position where the red
• 44:14
  Speaker 2: electron gun would eventually sit, so.
• 44:16
  Speaker 1: The light travel is exactly the same path the electronical.
• 44:19
  Speaker 2: Travel Exactly the UV light goes through the microscopic holes,
• 44:22
  Speaker 2: strikes the glass and hardens the red phosphor into tiny
• 44:26
  Speaker 2: dots in the exact right geometric locations. They wash away
• 44:29
  Speaker 2: the unhardened slurry. Then they coat the screen in green phosphor,
• 44:33
  Speaker 2: move the UV light to the green gun position, and
• 44:35
  Speaker 2: expose it again. Then they do it a third time
• 44:38
  Speaker 2: for the blue.
• 44:39
  Speaker 1: That is incredibly clever. It's a self aligning system.
• 44:41
  Speaker 2: And because of slight imperfections in every single piece of metal,
• 44:45
  Speaker 2: that specific shadow mask and that specific glass screen became
• 44:48
  Speaker 2: a married pair. They stay together for the rest of
• 44:51
  Speaker 2: the manufacturing process and went into the living room as
• 44:54
  Speaker 2: a single, inseparable unit.
• 44:56
  Speaker 1: But I want to go back to my cardboard spray
• 44:58
  Speaker 1: paint analogy, because there's a fundamental phys flaw I haven't mentioned.
• 45:01
  Speaker 1: What's that If I spray paint a piece of cardboard
• 45:03
  Speaker 1: to mask a dot on a wall, the cardboard just
• 45:06
  Speaker 1: gets wet with paint, But inside a CRT, we aren't
• 45:09
  Speaker 1: spraying paint. We are shooting subatomic particles traveling at tens
• 45:13
  Speaker 1: of thousands of miles an hour, carrying a massive amount
• 45:17
  Speaker 1: of kinetic and electrical energy. If the solid metal of
• 45:20
  Speaker 1: the shadow mask is blocking electrons, where does all that
• 45:23
  Speaker 1: kinetic energy go?
• 45:24
  Speaker 2: That question highlights the incredibly brute force inefficient nature of
• 45:29
  Speaker 2: this entire technology. The shadow mask is geometrically clever, but
• 45:34
  Speaker 2: from an energy standpoint, it is a disaster. To get
• 45:38
  Speaker 2: a clean picture, the solid metal of the mask has
• 45:41
  Speaker 2: to physically block about eighty five percent of the electrons
• 45:43
  Speaker 2: fired by the three guns.
• 45:45
  Speaker 1: Eighty five percent, so you are throwing away almost all
• 45:48
  Speaker 1: of the energy you generate. Only fifteen percent of the
• 45:50
  Speaker 1: beam actually makes it through the tiny holes to light
• 45:53
  Speaker 1: up the phosphor screen.
• 45:54
  Speaker 2: And those eighty five percent of blocked electrons don't just disappear,
• 45:57
  Speaker 2: They slam into the steel mask at all high velocity.
• 46:01
  Speaker 2: The law of conservation of energy dictates that kinetic energy
• 46:05
  Speaker 2: must transform. In this case, the rapid deceleration of the
• 46:08
  Speaker 2: electrons converts their kinetic energy into intense heat.
• 46:12
  Speaker 1: And what happens to a thin sheet of metal. When
• 46:14
  Speaker 1: you heat it up to hundreds of degrees inside a vacuum.
• 46:17
  Speaker 2: It expands. This caused a massive thermal engineering nightmare known
• 46:21
  Speaker 2: as doming. Imagine you're watching a TV show and there
• 46:25
  Speaker 2: is a very bright stationary object on the screen, like
• 46:28
  Speaker 2: a white logo or bright sun. To draw that bright
• 46:31
  Speaker 2: white object, the electron guns have to fire at maximum
• 46:34
  Speaker 2: intensity at one specific area of the.
• 46:36
  Speaker 1: Screen, meaning a massive concentration of electrons is slamming into
• 46:40
  Speaker 1: one specific spot on the shadow mass.
• 46:42
  Speaker 2: That localized spot of metal heats up rapidly. As the
• 46:44
  Speaker 2: steel heats up, it expands, and because the edges of
• 46:47
  Speaker 2: the mask are bolted down to a frame, the expanding
• 46:50
  Speaker 2: metal has nowhere to go but outward. It physically bulges
• 46:53
  Speaker 2: or warps towards the glass screen like a dome.
• 46:55
  Speaker 1: And if the metal warps, the microscopic holes move.
• 46:58
  Speaker 2: Even a microscopic shift ruins the geometry. If the mask
• 47:02
  Speaker 2: bulges by a fraction of a millimeter, the tiny hole
• 47:05
  Speaker 2: shift out of alignment with the phosphor doots on the glass. Suddenly,
• 47:09
  Speaker 2: the electron beam coming from the red gun passes through
• 47:11
  Speaker 2: the shifted hole and accidentally hits the green phosphor doot, and.
• 47:16
  Speaker 1: The bright white sun on the TV suddenly turns its
• 47:18
  Speaker 1: sickly muddy green.
• 47:19
  Speaker 2: Exactly, color purity is destroyed. So to fix a piece
• 47:22
  Speaker 2: of metal warping from heat inside a sealed glass vacuum tube,
• 47:26
  Speaker 2: engineers had to invent even more mechanical workarounds.
• 47:29
  Speaker 1: Oh boy, more work around.
• 47:30
  Speaker 2: They utilized heavily tensioned mounting frames. They welded the shadow
• 47:35
  Speaker 2: mass to a heavy steel ring using immense physical tension,
• 47:39
  Speaker 2: stretching the thin metal so tight it behaved like a drumhead, so.
• 47:42
  Speaker 1: Even if it heats up, the tension keeps it flat.
• 47:44
  Speaker 2: They also invented intricate by metal springs. These springs were
• 47:49
  Speaker 2: made of two different metals welded together that expand at
• 47:52
  Speaker 2: different rates when heated. They used these springs to attach
• 47:55
  Speaker 2: the mask frame to the glass. As the mask got
• 47:58
  Speaker 2: hot and tried to expand toward the screen, the bimetal
• 48:00
  Speaker 2: springs would heat up, curl backward, and mechanically pull the
• 48:04
  Speaker 2: entire mask assembly away from the glass to perfectly compensate
• 48:07
  Speaker 2: for the expansion.
• 48:09
  Speaker 1: I am marveling at the sheer insanity of this machine.
• 48:12
  Speaker 1: We're talking about a consumer appliance in the nineteen sixties,
• 48:15
  Speaker 1: where engineers are pumping massive amounts of high voltage subatomic
• 48:19
  Speaker 1: energy into a vacuum using acid edge to metal plates,
• 48:22
  Speaker 1: managing extreme thermal expansion with specialized tension springs. It sounds
• 48:27
  Speaker 1: like the inner workings of a nuclear reactor, not a
• 48:29
  Speaker 1: box you let your kids sit two feet away from
• 48:31
  Speaker 1: to watch cartoons.
• 48:32
  Speaker 2: Which is a perfect transition to the actual hazards of
• 48:35
  Speaker 2: this technology. We look back at old CRTs with nostalgia.
• 48:38
  Speaker 2: They were the warm, glowing hearth of the twentieth century
• 48:40
  Speaker 2: living room, but fundamentally, from an engineering perspective, they were heavy, fragile,
• 48:45
  Speaker 2: high voltage radiation boxers.
• 48:47
  Speaker 1: Let's talk about the danger. You mentioned that the shatter
• 48:49
  Speaker 1: mask blocks eighty five percent of the light producing electrons. Yeah,
• 48:53
  Speaker 1: if you lose eighty five percent of your light, the
• 48:55
  Speaker 1: picture on the screen is going to be incredibly.
• 48:57
  Speaker 2: Dim, unceptibly dim. To get a color picture that was
• 49:01
  Speaker 2: bright enough to actually watch in a sunlit living room,
• 49:03
  Speaker 2: the engineers had to massively overcompensate. They had to dramatically
• 49:08
  Speaker 2: crank up the power and intensity of the three electron
• 49:11
  Speaker 2: guns to punch enough energy through those tiny holes.
• 49:14
  Speaker 1: How much power are we talking about.
• 49:16
  Speaker 2: To accelerate the electrons fast enough to generate a bright
• 49:19
  Speaker 2: picture color CRTs required incredibly high anode voltages. We're talking
• 49:24
  Speaker 2: about feeding twenty five thousand to thirty thousand volts of
• 49:27
  Speaker 2: electricity into the back of the picture tube.
• 49:30
  Speaker 1: Thirty thousand volts inside a wooden cabinet in.
• 49:32
  Speaker 2: A home, and that extreme voltage introduces a physical phenomenon
• 49:36
  Speaker 2: known as bremstralong or breaking radiation. When you accelerate an
• 49:39
  Speaker 2: electron using thirty thousand volts, it is traveling at a
• 49:42
  Speaker 2: significant fraction of the speed of light. When that electron
• 49:45
  Speaker 2: suddenly slams into the dense metal of the shadow mask
• 49:48
  Speaker 2: or the phosphor coating on the glass, it decelerates instantly.
• 49:52
  Speaker 1: And we know from earlier that the kinetic energy turns
• 49:54
  Speaker 1: into heat.
• 49:55
  Speaker 2: Most of it turns into heat, but at those extreme voltages,
• 49:59
  Speaker 2: a small percentage of that kinetic energy is released as
• 50:02
  Speaker 2: high energy electromagnetic photons. Specifically, it generates actual measurable X
• 50:08
  Speaker 2: ray radiation.
• 50:09
  Speaker 1: Wait pause, you were telling me that the television set
• 50:14
  Speaker 1: in the living room was actively functioning as an X
• 50:16
  Speaker 1: ray machine, emitting radiation directly at the family sitting on
• 50:20
  Speaker 1: the couch.
• 50:21
  Speaker 2: It was a very real, very serious engineering concern. The
• 50:24
  Speaker 2: tube itself was generating X rays. To protect the viewer
• 50:28
  Speaker 2: from absorbing that radiation, the glass on the front of
• 50:31
  Speaker 2: the CRT had to be completely redesigned. It couldn't just
• 50:34
  Speaker 2: be normal window glass.
• 50:35
  Speaker 1: That wouldn't stop X rays right.
• 50:36
  Speaker 2: It had to be incredibly thick, sometimes over an inch
• 50:39
  Speaker 2: thick at the front. And more importantly, the glass was
• 50:41
  Speaker 2: heavily laced with elements that block radiation, like lead, the.
• 50:44
  Speaker 1: Way you wear a lead apron at the.
• 50:46
  Speaker 2: Dentist exactly, the glass of a color CRT was heavily
• 50:50
  Speaker 2: loaded with lead oxide. The front panel, which the viewer
• 50:54
  Speaker 2: looked through, also contained large amounts of specialized heavy metals
• 50:58
  Speaker 2: like strontium and barium, which are highly effective at absorbing
• 51:02
  Speaker 2: X rays while remaining transparent to visible light. The engineers
• 51:06
  Speaker 2: had to build a transparent radiation shield into the front of.
• 51:09
  Speaker 1: The TV, which explains the weight. That's why those old
• 51:12
  Speaker 1: color TVs were practically immobilized. You're trying to lift a
• 51:15
  Speaker 1: giant block of thick lead and fused glass.
• 51:17
  Speaker 2: A large twenty seven inch color CRT could easily weigh
• 51:21
  Speaker 2: over one hundred pounds, and that sheer mass, combined with
• 51:24
  Speaker 2: the physical vacuum in side, made the device physically dangerous
• 51:28
  Speaker 2: if handled improperly.
• 51:29
  Speaker 1: Right because earlier we established that the inside is a
• 51:32
  Speaker 1: near perfect vacuum, meaning all the air pressure of the
• 51:35
  Speaker 1: room is pushing on the outside of the glass, but
• 51:37
  Speaker 1: nothing is pushing back from the inside.
• 51:39
  Speaker 2: The atmospheric pressure exerting force on the outside of a
• 51:42
  Speaker 2: large CRT amounts to several tons of crushing weight. The
• 51:47
  Speaker 2: thick leaded glass is structurally designed to withstand that inward pressure.
• 51:51
  Speaker 2: But if you dropped a CRT or accidentally struck the
• 51:54
  Speaker 2: neck of the tube and crack the glass, the structural
• 51:57
  Speaker 2: integrity failed.
• 51:58
  Speaker 1: You wouldn't just shatter and fallow the floor.
• 52:00
  Speaker 2: No, it would cause a violent, terrifying event called an implosion.
• 52:04
  Speaker 2: The instant the glass cracked, the vacuum would violently suck
• 52:08
  Speaker 2: all the heavy leaded glass shards inward toward the center
• 52:11
  Speaker 2: of the tube at immense speeds. The shards would crash
• 52:14
  Speaker 2: into each other in the center, rebound, and shoot outward
• 52:17
  Speaker 2: in every direction into the room like shrapnel.
• 52:19
  Speaker 1: High voltage, literal X ray radiation, toxic heavy metals, and
• 52:24
  Speaker 1: a permanent risk of a glass shrapnell Bob. It's a miracle,
• 52:27
  Speaker 1: and entire generation survived the twentieth century. We made it
• 52:30
  Speaker 1: through knowing how dangerous, inefficient, and convoluted the shadow mask was.
• 52:35
  Speaker 1: Did anyone try to invent a safer, better way to
• 52:37
  Speaker 1: do this before flat screens came along?
• 52:39
  Speaker 2: Absolutely. While RCA's shadow mask dominated the global market for
• 52:43
  Speaker 2: decades because it was first, other brilliant engineers recognized the
• 52:47
  Speaker 2: absurdity of blocking eighty five percent of the electrons. The
• 52:51
  Speaker 2: most famous alternative was developed by Sony in the late
• 52:54
  Speaker 2: nineteen sixties. They introduced a completely different tube architecture called
• 52:59
  Speaker 2: the trinitron.
• 53:00
  Speaker 1: Remember the name Trinyitron. They were incredibly popular in the
• 53:03
  Speaker 1: eighties and nineties, especially for high end computer monitors. How
• 53:06
  Speaker 1: was it different from RCA's mask.
• 53:09
  Speaker 2: Instead of a metal sheet with tiny round holes, the
• 53:12
  Speaker 2: trinitron used something called an aperture grill. It was a
• 53:15
  Speaker 2: series of unbroken, vertically suspended, incredibly thin metal wires pulled
• 53:20
  Speaker 2: under immense tension. Imagine a microscopic metal harp inside the TV.
• 53:24
  Speaker 1: So there are no horizontal metal pieces blocking the beam,
• 53:27
  Speaker 1: just vertical slits.
• 53:28
  Speaker 2: Exactly because there was so much less metal in the way.
• 53:31
  Speaker 2: The aperture grill allowed a vastly higher percentage of the
• 53:34
  Speaker 2: electrons to pass through and hit the phosphor stripes on
• 53:36
  Speaker 2: the glass. The result was a significantly brighter, sharper, and
• 53:40
  Speaker 2: more vibrant picture than the traditional shadow mask.
• 53:42
  Speaker 1: And if you ever looked really closely at a white
• 53:45
  Speaker 1: scream and or old trenitron monitor, you could actually see
• 53:48
  Speaker 1: two tiny, saint horizontal lines. Those were the ultra thin
• 53:53
  Speaker 1: support wires holding the vertical grill in place.
• 53:56
  Speaker 2: You could there were other attempts too. Philco developed an
• 53:59
  Speaker 2: experiment mental CRT called the Apple Tube. It tried to
• 54:02
  Speaker 2: eliminate the physical mask entirely. It used a single electron
• 54:06
  Speaker 2: beam and painted special UV emitting index stripes on the
• 54:10
  Speaker 2: back of the screen. As the beam swept across, a
• 54:13
  Speaker 2: sensor would detect the UV flashes, telling the TV's computer
• 54:16
  Speaker 2: exactly where the beam was, allowing it to rapidly switch
• 54:19
  Speaker 2: the electron gun between red, green, and blue data on
• 54:22
  Speaker 2: the fly.
• 54:22
  Speaker 1: That is software solving a hardware problem. That sounds vastly superior.
• 54:27
  Speaker 1: Why didn't we all have Apple tubes?
• 54:29
  Speaker 2: It was brilliant in theory. It would have meant much
• 54:31
  Speaker 2: brighter screens and no heavy metal masks. But the high
• 54:34
  Speaker 2: speed computing electronics required to process that index signal in
• 54:37
  Speaker 2: real time were just too complex and expensive for the
• 54:40
  Speaker 2: analog technology of the nineteen fifties and sixties. It was
• 54:43
  Speaker 2: an idea ahead of its time, and it never caught
• 54:46
  Speaker 2: on commercially.
• 54:47
  Speaker 1: So the brute force RCA shadow mask and the NTSC
• 54:50
  Speaker 1: electronics subcarrier standards really did conquer the world. But before
• 54:55
  Speaker 1: we wrap up the timeline, I have to bring up
• 54:56
  Speaker 1: a funny historical quirk about that NTSC standard. We've praised
• 55:00
  Speaker 1: it as a miracle of math hiding color in the
• 55:03
  Speaker 1: subcarrier gaps, but it wasn't perfect in practice, was it.
• 55:07
  Speaker 2: No, The NTSC analog signal had a glaring vulnerability to physics.
• 55:12
  Speaker 2: While hiding the color data was brilliant. Extracting that data
• 55:16
  Speaker 2: reliably in a home relied on perfect synchronization. The TV
• 55:19
  Speaker 2: had to read the exact timing the phase of that
• 55:22
  Speaker 2: three point five to seven megahertz subcarrier wave.
• 55:25
  Speaker 1: What happens if the timing gets messed up.
• 55:26
  Speaker 2: The analog radio wave was highly susceptible to environmental interference, specifically,
• 55:31
  Speaker 2: something kind of multipath distortion. Imagine the radio wave leaves
• 55:35
  Speaker 2: the broadcast tower. Part of the wave travels in a
• 55:37
  Speaker 2: straight line directly to the antenna on your roof, perfect
• 55:39
  Speaker 2: but another part of that exact same wave shoots off
• 55:42
  Speaker 2: to the side, bounces off a large water tower or
• 55:44
  Speaker 2: an airplane flying overhead, and reflects back to your antenna.
• 55:48
  Speaker 2: That reflected wave arrives a tiny fraction of a millisecond
• 55:50
  Speaker 2: later than the direct wave.
• 55:52
  Speaker 1: So the TV is receiving two identical signals, but one
• 55:55
  Speaker 1: is slightly delayed. There out of phase exactly.
• 55:58
  Speaker 2: The TV's color decoder gets confused by the overlapping waves.
• 56:02
  Speaker 2: It interprets that slight delay in the phase of the
• 56:04
  Speaker 2: subcarrier wave as a mathematical instruction to change the color hue.
• 56:08
  Speaker 2: The colors would drift randomly on the screen. The sky
• 56:11
  Speaker 2: might suddenly turn a sickly green, or news inc anchor's
• 56:14
  Speaker 2: face might shift to a deep purple. Viewers had to
• 56:17
  Speaker 2: constantly get up and tweak a physical tint or Q
• 56:20
  Speaker 2: knob on the front of the TV to manually correct
• 56:22
  Speaker 2: the math.
• 56:22
  Speaker 1: Yes, TV engineers famously used to joke that NTSC actually
• 56:26
  Speaker 1: stood for never the same color or no true skin colors.
• 56:29
  Speaker 2: It was a very real frustration for broadcasters. In fact,
• 56:32
  Speaker 2: because the United States rushed to adopt color TV so
• 56:36
  Speaker 2: early in nineteen fifty three, the rest of the world
• 56:38
  Speaker 2: had the luxury of waiting and learning from our analog mistakes.
• 56:42
  Speaker 2: A decade later, engineers in Europe developed vastly improved, mathematically
• 56:46
  Speaker 2: complex standards called papal and scam.
• 56:49
  Speaker 1: Oh I've seen those acronyms on old DVDs.
• 56:51
  Speaker 2: Yeah, these systems used clever phase alternating math to automatically
• 56:55
  Speaker 2: cancel out those reflection errors. That is why European analog
• 56:59
  Speaker 2: televis and generally had much more stable, accurate color than
• 57:03
  Speaker 2: American television for decades.
• 57:05
  Speaker 1: It's the ultimate penalty of being the early adopter. You
• 57:09
  Speaker 1: get the miraculous technology first, but you're stuck living with
• 57:12
  Speaker 1: the bugs of version one point zero for the next
• 57:14
  Speaker 1: fifty years. So wrap up this massive historical timeline force.
• 57:19
  Speaker 1: The NTSC standard is approved in nineteen fifty three, when
• 57:23
  Speaker 1: does the CRT actually take over the world.
• 57:26
  Speaker 2: It was an incredibly slow burn. Even though the compatible
• 57:29
  Speaker 2: electronic standard was approved, early color TVs were still prohibitively expensive,
• 57:33
  Speaker 2: costing thousands of dollars, and for years networks only broadcast
• 57:36
  Speaker 2: a few hours of color programming a week. The vast
• 57:39
  Speaker 2: majority of the public stuck with their reliable black and
• 57:42
  Speaker 2: white sets. It wasn't until the early nineteen seventies that
• 57:45
  Speaker 2: sales of color televisions finally surpassed black and white sets
• 57:48
  Speaker 2: in the United States.
• 57:49
  Speaker 1: It took twenty years for color to become the norm.
• 57:51
  Speaker 2: But once it did, the color cathode ray tube dominated
• 57:54
  Speaker 2: the global cultural landscape entirely. It defined the esthetics of
• 57:58
  Speaker 2: the late twentieth century. It was the absolute, unquestioned king
• 58:03
  Speaker 2: of the living room, the arcade, and the office desk
• 58:05
  Speaker 2: until the late two thousands, when the manufacturing of flat panels,
• 58:09
  Speaker 2: LCDs and olds finally advanced enough to become cheap and vibrant.
• 58:13
  Speaker 2: Only then does society finally replace the heavy, toxic, power hungry,
• 58:17
  Speaker 2: dangerous crt once and for all.
• 58:20
  Speaker 1: Wow, let's take a breath and summarize this incredible journey
• 58:23
  Speaker 1: for everyone listening. We started with a massive post war
• 58:26
  Speaker 1: industry boom that created an impossible economic bottleneck fifteen million
• 58:31
  Speaker 1: existing TVs. We looked at the clunky, terrifying spinning mechanical
• 58:35
  Speaker 1: wheel that threatened to render all those TVs obsolete and
• 58:38
  Speaker 1: spark our retail apocalypse.
• 58:39
  Speaker 2: And we tracked a corporate war that went all the
• 58:41
  Speaker 2: way to the Supreme Court, only to be halted by
• 58:43
  Speaker 2: the geopolitical reality of the Korean War.
• 58:45
  Speaker 1: We witnessed a genius mathematical compromise that literally hid invisible
• 58:49
  Speaker 1: color data in the microscopic frequency gaps of a radio signal.
• 58:53
  Speaker 1: And finally we explored the physical reality of a heavy
• 58:57
  Speaker 1: lead lined, implosion risk glass box that showed thirty thousand
• 59:00
  Speaker 1: volts of subatomic particles through an acid etched metal sieve,
• 59:04
  Speaker 1: losing eighty five percent of its energy as heat, just
• 59:07
  Speaker 1: to bring a moving picture into your home.
• 59:09
  Speaker 2: It truly is a testament to human ingenuity. It demonstrates
• 59:12
  Speaker 2: the sheer willpower of engineers to solve seemingly impossible constraints,
• 59:16
  Speaker 2: and it also shows our collective societal willingness to accept
• 59:20
  Speaker 2: incredibly convoluted brute force solutions and even a certain amount
• 59:24
  Speaker 2: of physical danger if the end result provides us with
• 59:27
  Speaker 2: something we desire as deeply as entertainment and visual information.
• 59:30
  Speaker 1: It's an amazing story and it completely changes how I
• 59:33
  Speaker 1: look at the screens around us today. We've gone from
• 59:35
  Speaker 1: heating metal to boil off electrons to quietly vibrating liquid
• 59:39
  Speaker 1: crystals with almost zero power. If you enjoy this wild
• 59:43
  Speaker 1: history as much as I did, don't forget to rate
• 59:44
  Speaker 1: Kriscassack podcast Science revealed five stars to help keep these
• 59:48
  Speaker 1: educational journeys coming.
• 59:49
  Speaker 2: And I want to leave you with a final thought,
• 59:51
  Speaker 2: tim all over, as you look at your screens today,
• 59:54
  Speaker 2: As we've discussed at length, the color TVCRT was essentially
• 59:57
  Speaker 2: a massive, highly dangerous, in incredibly inefficient brute force workaround.
• 1:00:03
  Speaker 2: It blocked eighty five percent of its own energy just
• 1:00:05
  Speaker 2: to function, It required tension springs to stop from warping,
• 1:00:09
  Speaker 2: It generated X rays, and it weighed one hundred pounds.
• 1:00:11
  Speaker 2: Yet for fifty years, billions of people accepted it unquestioningly
• 1:00:16
  Speaker 2: as the absolute, perfect technological standard of modern life.
• 1:00:20
  Speaker 1: It's very true.
• 1:00:21
  Speaker 2: So as we look around at our cutting edge world today,
• 1:00:23
  Speaker 2: at our complex digital infrastructure, our massive artificial intelligence server farms,
• 1:00:28
  Speaker 2: our electric vehicle battery grids, what piece of technology that
• 1:00:31
  Speaker 2: we currently accept is the absolute standard is actually just
• 1:00:34
  Speaker 2: a messy, inefficient workaround. What are we relying on right
• 1:00:37
  Speaker 2: now that future generations will look back on in fifty
• 1:00:40
  Speaker 2: years and laugh at wondering how we ever lived with
• 1:00:42
  Speaker 2: such a clunky, dangerous monster in our daily lives.
• 1:00:45
  Speaker 1: That is a brilliant, provocative question to end on. I'll
• 1:00:49
  Speaker 1: be thinking about that all week. Thank you so much
• 1:00:51
  Speaker 1: for joining us on this exploration today. To all our
• 1:00:54
  Speaker 1: listeners out there, keep questioning the world, keep looking deeper
• 1:00:57
  Speaker 1: into the hidden mechanisms of the everyday science surround at
• 1:01:00
  Speaker 1: you and we will see you next time.