alt.hn

3/31/2026 at 7:12:54 PM

Why Inventing Color TV Was So Difficult [video]

 https://www.youtube.com/watch?v=hyjCmIbRRvs

by DamnInteresting

4/4/2026 at 2:39:31 PM

I grew quite an appreciation of color TV recently when I made a software-defined SECAM decoder. It's mind-boggling that they were able to do this with 60s technology, to be honest. But then what do I know, analog electronics is witchcraft to me :D

https://github.com/grishka/miscellaneous/blob/master/AVDecod...

edit: I watched the video. It only took them until the 13th minute of a 15-minute video to show something resembling a real video waveform, lol. That's, uh, not how you explain how TV works.

by grishka

4/4/2026 at 2:56:58 PM

SECAM was pretty crazy because it required a delay line: a memory that would hold the previous scanline so it can be combined with the current one.

Without digital circuits, the delay line was a piece of glass. You’d convert the video signal to a sound wave, send it through the glass, and (hopefully) get it back exactly 64 us later so it aligns with the next scanline.

Here’s a picture: https://www.eevblog.com/forum/projects/glass-ultrasonic-dela...

by pavlov

4/4/2026 at 8:18:20 PM

Yes I did read about these while doing my research. Also fascinating. Most (or maybe all?) PAL TVs also have a delay line to correct for phase errors. That ability is what differentiates PAL from NTSC, apart from timing.

by grishka

4/4/2026 at 5:19:37 PM

Fascinating! So it's a bit like a plate reverb (used in the olden days in audio engineering), but in the MHz range.

by lbourdages

4/4/2026 at 1:50:09 PM

In the first 90 seconds, the narration refers to "the insane 19th century electronics that made color possible", but is referring to the 1900s, which were the 20th century.

The video contains no insight at all into "why" color TV was so difficult. It just lists and describes a few key advancements.

Also the "invention" of color TV is very different from the commercialization.

by mpalmer

4/4/2026 at 3:05:39 PM

Very common for this format. It looks and sounds like something of substance on the surface, but ultimately it's just going through the motions and droning on to fill 10 minutes. Like a high-schooler with an assignment to give a presentation on some topic, but with higher production quality.

It does not have to be coherent, because it's entertainment, closer to a sitcom than educuation. If you think about it too hard you'll ruin it for yourself.

Before you blame YouTube and AI though, have a look at what documentaries on TV are and used to be like. With few exceptions they're not much better.

by chmod775

4/4/2026 at 4:12:19 PM

I disagree. I think the video clearly described the challenge, somewhere in the middle of the video, as sending TV signals that both BW and color TV sets could decode, and went on to explain how that challenge was solved by "inventing" separate Luma and Chroma signals. Did I miss something?

by pack_stimulus

4/4/2026 at 2:43:07 PM

Tintin readers will remember the pains suffered by viewers of early color TV experiments (“The Castafiore Emerald”, 1961).

by pavlov

4/5/2026 at 6:13:43 AM

Thanks for the Tintin reference! I immediately knew what you mentioned as that panel flashed in my mind.

I don't know what it is about the Tintin comics, but for many of the fans, the panels are so strongly memorable even after so many years, is quite amazing.

by thunderbong

4/4/2026 at 1:53:11 PM

Before Youtube and Wikipedia there used to be a great website I liked to read about Philo Farnsworth but cannot remember the name of it for the life of me now

by ck2

4/4/2026 at 1:59:42 PM

farnovision.com ?

by reader9274