Beginners guide to B&W tube TV restoration part 13 (vertical sync)

Let's get the vertical sync working.
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[@Delatsch]

These are priceless explanations for us who grew up after the era and have no clue about these complicated circuits. Keep them coming!

[@greggsvintageworkshop8974]

Very good video Bob! I am absorbed by each circuit as you explain the purpose and show how and why it does what it does. You are a GREAT teacher sir!

[@erin19030]

A very good practical explanation for beginners.

[@radio-ged4626]

Isn't this fun? Well yes, in a sense it is. You've refreshed knowledge I gained 40 years ago and given me a hit of nostalgia. I hope that people watching this who are new to this field of work are as interested as I am. If they are then this sort of knowledge won't be lost. It's the background technology that got us to where we are today and I think it's important that a proportion of the people interested in electronics and information technology at least have a sense of what was before. A great explanation of how sync separation works, it's hard to explain the separation of a composite signal and you make it look a lot easier than it would be to a lot of people with the same knowledge (me included).

[@susantempleton7754]

Best thing I’ve ever seen on the theory of synchronization-more accessible than even the best textbooks covering the topic. Thank you!

[@bandersentv]

Glad it was helpful

[@tennesseered586]

Very informative. Gotta get me an old TV to tinker with.

[@jogiemka]

Thank you, thank you thank you. Fantastic information, and you are an awesome teacher!

[@PodeCoet]

Absolutely loving this series, really appreciate the hard work!

[@dontknowbrian]

WOW! You got me hooked!

[@mikefinn2101]

So glad to get a new video been waiting for days

[@maskddingo1779]

Chief O'Brien helping out at the end 😂

[@PracticallyFixed]

Man, this is great stuff. Thank you

[@ACockburn1967]

Isn't this fun? Yes!

[@SeekingTheLoveThatGodMeans7648]

VERY early television systems (with physical scan systems) did not support sync information in the signal, and their scan speed had to be "driven" or constantly adjusted by the person operating the picture receiving equipment, to match what the transmitting equipment was using and thus to produce as straight a picture as possible.

[@eDoc2020]

SOME needed manual speed adjustments. I believe most used synchronous motors so the power grid provided a precise frequency match. Then you only needed to adjust the phase by hand.

[@markseymour5558]

Most basic explanation of why there is vertical and horizontal circuits, think of the electron beam striking the phosphors as a paint brush, the vertical tells the brush to start at the top and work its way to the bottom, horizontal tells the brush to work from left to right, otherwise the brush would be painting all over the place

[@erin19030]

The vertical integral pules is packed with equalizing pulses,too. Your new scope is vary capable of showing all this pulse date. You can even pull one pulse off at at it in once trace.

[@zundfolge1432]

I much prefer the book banderson beginners guide to b&w tv over grob. I might have even bought the mentioned grob book dont remember. Im sure as heck gonna keep this series on constant replay!

[@directcurrent5751]

Excellent presentation. Must have taken months of engineering team effort to finallze the RCA standards.

[@55benchguy]

This was always a problem in the older sets. I remember building these on terminal strips. But , mine never worked as well as the original LOL.

[@erin19030]

Now you can all see what capacitors and resistor do.

[@alexinnewwest1860]

Great explanation. I was struggling a bit to understand the vertical sync system and this cleared it up: One question. If our broadcast system is interlaced with two fields. How does the set control between each field and choose the correct field when turned on or change a station etc Thanks

[@bandersentv]

Hi. It doesn't need to. There is a half line offset baked into the composite video signal that naturally caused the fields to be offset by one line as they are painted on the screen.

[@alexinnewwest1860]

Ah ok thanks. I think I get it 🫨

[@notimetolooz9655]

15750 divided by 60 equals 262.5 (lines). In 1954 color broadcasting began and a color reference of 3.579545MHz was used. It was decided to change the sweep frequencies to be related to this reference. 15734 divided by 59.94(about) equals 262.5(lines). These new frequencies are so close to the old ones it doesn't matter to the old sweep circuits, however all modern NTSC modulation uses the newer frequencies. @@alexinnewwest1860

[@mateuszsp8ebc691]

Could You please tell, how the book You show in about 22 minutes of video is titled?

[@bandersentv]

Basic Television by Grob. I talk about it and others in the episode on finding service info

[@mateuszsp8ebc691]

@@bandersentv thank You for an answer. I ve missed that episode

[@quetzal4042]

20:15 "for the horizontal.....so you use a low-pass filter on that." Didn't you mean to say "high-pass filter"?

[@bandersentv]

Yes, I sure did!