You have a wealth of the kind of curiosity and clarity that is in seemingly short supply these days, even among science content creators. I am looking forward to the day when this channel becomes a household name among enthusiasts. Hats off to you.
my physics teacher was an RF engineer in television industry and he used to explain us stuff about it outside of our physics lessons. one thing that I remember him explaining is that somehow the frequency domain of different TV channels were not 1d frequency ranges, but instead somehow 2d rectangular areas because they used 2 orthogonal modulation methods at the same time. for god's sake i can't remember the details because it was way over my head. there was also very interesting maths about how signal frequency range splits when you apply FM and AM modulation at the same time, then you cut off a mirrored part of the spectrum, then your signal becomes complex, then you do some magic to recover it during demodulation. it's actually crazy, the pervious generation of engineers was amazing.
At the time I was a student at the MTS in Alkmaar studying electronics I sometimes came across old televisions placed on the street to be picked up by the garbage truck when cycling home to Heerhugowaard. I then opened up the back of the television and took out the large A2 size schematics which was included inside of the tv. I then spend hours figuring out how that TV worked. If I now open up a new tv, unfortunately no schematics inside. Just a few boring chips. I always found it very clever how they came up with the transition from black and white to the color in the signal in PAL. We also used to say NTSC stands for, Never The Same Colour. Nostalgia!
They way you are able to explain things is phenomenal. Great instructions, calm explanations, thorough and in-depth, great examples, great drawings. Absolutely fantastic! very much in love with your channel. Dank u wel meneer Huygens ! :)
I loved that intro. Your family is adorable -- especially the new addition. The whole video was great. I had a very similar tv but with a built in VCR (another crazy piece of related tech). When I was quite young I found a signal generator that I put through my composite video and many interesting patterns appeared. This sort of reminds me of that except you know what you're doing.😅
I never knew about the transmission part of the whole analog TV process, super interesting! It's interesting how ycbcr is still very much alive in modern image and video applications. I had always assumed ycbcr was somehow natively understood by the way they built color CRTs but it never clicked for me that those devices too need to translate to RGB. Not much has changed in that regard these days. Fijne kerst!
Subscribed and selected to be notified. I found your channel looking into optical flats and was very interested in the bubble level you built for your dad... good stuff. Now I'm blown away, what great content!!! Anyone who is curious on the kind of level you are and willing to take the time and effort to share it deserves high praise. Good job sir, a very good job indeed.
Fantastic explanation! Finally I understood something I just wondered since I was a teenager trying to know how things work. I read about some crazy hard math stuff and let it go but it is relatively so simple! Thanks a lot. Really.
I spent a good part of my electrical engineering career working on demodulators for analog TV. It's, by far, the most difficult signal I've ever worked with, the spurious-free SNR requirements alone were >70dB on a 40" HDTV, and that doesn't get to the hard stuff. I became the guy they would send to that 2hr meeting at LG in S. Korea, because there was no alternative to seeing the video impairments first hand.
I bought such stuff for around 70000 deutschmarks in the beginning of the nineties last century. It was for a video conferencing equipment development.
Not much long ago I rescued a similar sized (but much more modern) set in the same situation. It's like rescuing stray puppies. I'm an EE now, and my fascination came about by trying to understand how it all worked, and the answers just taking me deeper. (consider I'm on the younger end of millennial)
i honestly think that back in the days of analog circuitry being an engineer might have been the hardest time to be an engineer. sure, modern high density digital electronics are way more complex, but it's always possible to break them down to trivial enough components. but back then it was simply not the case: analog circuitry is like a hairball that you can't simplify past a certain point.
Fantastic video! While I am subscribed for your fantastic optics content, I really liked this one also. As other have said, your explanation skills are amazing.
So you could attach the Pb and Pr signals of a video stream to an X/Y oscilliscope to get a visualization of what areas of the color space are being used.
19:38 I think this explanation is somewhat imprecise. TV uses vestigial sideband modulation (AM with lower sideband mostly filtered out). What you describe fits more FM modulation. Plus, on a conceptual level there's nothing that forbids multiple sinewaves to coexist, as per superposition principle. The signal on oscilloscope looks just like a jumping sinewave because it's narrowband compared to the carrier frequency. It would have different instantaneous shape only if there were any harmonics, which don't occur in well-behaved radio transmissions.
I wonder if by using this absolutely fantastic signal generation tools and maybe PC for control you can make some kind of randomly generated demo-like video on analog TV. As I saw the RS generator runs on MS-DOS, which makes it easier to tinker with its software.
I'm very confused about why the transmitter displays an intermediate frequency. As you explained, IF is an implementation detail of the receiver, and the math of applying modulation onto an IF doesn't require the signal to know anything about the IF, so I don't know what the transmitter could possibly have to do with it. It's like if the transmitter had a display for "screen-to-viewer distance" - it could be different for each receiver, and wouldn't affect the signal anyway.
@@HuygensOptics I could not figure out the spelling...great stuff...replace the tubes with FETs on paper or in mind to be able to look at the old tube schematics. At least to understand the paths and control mechanisms. Also will pick up a signalhound, been wanting to get a good enough SA for home.
