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Under Section Modulators

"...many TV sets sold these days no longer have analogue television tuners and cannot accept channel 3/4." Is there a shred of factual data to support this? Except for the brief blip in time around 2005 when "monitors" without built in dual NTSC, or ATSC or Clear QAM tuners I can not find the above quote to even to this day be a true statement as an AVID TV purchaser / shopper. — Preceding unsigned comment added by 66.188.252.171 (talk) 13:21, 8 July 2014 (UTC)[reply]

I know it is true for DVD recorders. They stopped putting in NTSC tuners, and mostly didn't put in ATSC tuners. For cable users with a converter box, there is no need for any tuner. Presumably there is a phase out, but I don't know how fast. Gah4 (talk) 18:53, 17 August 2017 (UTC)[reply]

Illustration

Would it be possible if someone made an illustration or graph of how it is done getting 3 signals (YUV) in one "plug" with only 2 connectors? I'm very curious about that, atleast, but dont nearly have enough background knowledge to do it. anon 10:56, Jun 17, 2010 (UTC)

The voltages in the diagram are all wrong.

In U.S. NTSC, blanking is at 0 volts (0 IRE), the sync tips are at -0.286 volts (-40 IRE), and peak white is at +0.714 volts (100 IRE). The peak-to-peak amplitude is 0.286 + 0.714 volts, or one volt. Setup (pedestal) is +0.05355 volts (7.5 IRE). — Preceding unsigned comment added by Chris319 (talk • contribs) 06:11, 14 July 2017 (UTC)[reply]

Initialisms

In the 60's/70's some wag came up with some alternate words for the abbreviations:

NTSC "Never Twice the Same Colour"
SECAM "System Essentially Contrary to the American Method"
PAL "someone please fill this in and check" "Perfection All Lines"? <-- "Picture at Last"

If I remember right it was heavily biased to PAL Archivist 00:55, Nov 15, 2003 (UTC)

I knew SECAM as "Shows Every Colour All Murky"

20.133.0.13 (talk) 14:05, 24 March 2009 (UTC)[reply]

I always learnt "Système Elégant Contre les AMéricains" though I also came across "Sans Experience contre les Americains" The Seventh Taylor (talk) 13:03, 29 September 2011 (UTC)[reply]

CVBS initalism

Regarding CVBS, the article states: "CVBS initialism, meaning "Composite Video, Blanking, and Sync". I've also come across Composite Video Broadcast Signal and ~ Baseband Signal. Even Composite Video, Burst, and Sync. Which is it? Is there an authoritive reference for this? The Seventh Taylor (talk) 13:06, 29 September 2011 (UTC)[reply]

According to the Dictionary of Electronics, Fourth Edition, Newnes, 1999, edited by S.W. Amos, R. S. Amos and G.W.A. Dummer, appendix , page 365, CVBS stands for "compositve video blanking and synch". Good enough for me. --Wtshymanski (talk) 14:45, 29 September 2011 (UTC)[reply]

Actually, CVBS has various definitions, Color Video Blanking Signal should be making the most sense - 'Composite' is all this combined and 'Blanking' and 'Sync' is somewhat the same thing. In German it's FBAS - Farb-Bild-Austast-Signal. I can also find

Composite Video Baseband Signal
Composite Video Burst Signal
Composite Video, Burst and Sync
Color, Video, Blanking, Synchronization
Colour Video Blanking Sync
Composite Video Broadcast Signal

in common use. All of these make sense and are from relevant sources. I'd guess we won't be able to trace this back in time to its definition. Any notion for adding at least the more popular definitions to the article? Zac67 (talk) 20:29, 21 October 2011 (UTC)[reply]

Cite it and write it. --Wtshymanski (talk) 21:52, 22 October 2011 (UTC)[reply]

RCA/BNC

Since the Yellow RCA connector is by far the most common connector, the term "yellow-plug video" has been suggested to help cut down on confusion between "composite" and "component" (which sound somewhat similar).

Samurai: what the hell does "commercial variations of video media" mean?

Why _IS_ composite referred to as RCA/BNC?

- 67.118.29.33 10:38, 31 Mar 2005 (UTC)

          Composite is referred to as RCA/BNC because those are the types of connecters used on the ends of the cable.
          An RCA plug is the common "yellow plug" video that is mentioned above.  BNC is an older style connecter that 
          attaches to coaxial cable.  BNC connectors can be found on old networking cards and all oscilliscopes.
                       mboylevt

BNC connectors are the professional choice and most professional video equipment will use BNCs for video input and output (composite, component, RGBHV, and in some cases even S-video); the RCA ("phono") connector is a poor connector in general, and regarded as particularly poor for video based on its electrical/shielding characteistics. BNC connectors are locking, mantain proper impedance and offer better shielding performance. Lincoln 69.17.11.103 17:35, 18 February 2007 (UTC)[reply]

The RCA plug has one major advantage over the BNC for consumer use which is why it is used - it's cheaper. 86.182.71.209 (talk) 17:05, 5 March 2011 (UTC)[reply]

Modulation channel

Every piece of consumer equipment I've used in the USA in the past 25 years modulated the signal onto channel 2 or 3 (not 3 or 4), what am i missing?

I have never, ever owned a piece of equipment that modulated the signal into channel 2. Always 3 or 4. Liquidtenmillion 00:51, 15 April 2006 (UTC)[reply]

I have never seen 2, but it is possible. Broadcast TV avoids using channels with no frequency gap between them. Some areas have 2 and 4, others 3. (There is a gap between 4 and 5, such that they can occur together.) Gah4 (talk) 19:01, 17 August 2017 (UTC)[reply]

Frequency

What is the normal frequency composite uses?

What is the typical and maximum equivalent resolution of video information carried by the CVBS format? 480 lines? Glueball (talk) 11:26, 13 May 2008 (UTC)[reply]

Unlike television channels, which are modulated onto an RF carrier, composite video is baseband. The signal ranges from 0Hz to about 4.5MHz. Television channels are about 6MHz wide, described variously as the lower end, the center, or the carrier frequency. US TV channel 2 is from 54 to 60MHz, for example, with the carrier at 55.25MHz.

Gah4 (talk) 09:18, 2 June 2008 (UTC)[reply]

Noise

The process of modulating RF with the original video signal, and then demodulating the original signal again in the TV, introduces several losses. This conversion also typically adds noise or interference to the signal as well. Other than noise, what are the losses? In theory, one can modulate an ideal carrier, and demodulate it again. The low signal levels of RF (it has to match what one could receive on an antenna) means noise is significant. (You can't escape thermal noise.) Generating a proper vestigial sideband signal is also tricky, but again, it can ideally be done without loss. Spectral errors aren't really losses, either. Gah4 (talk) 16:59, 28 May 2016 (UTC)[reply]

Revert of new section about history of connectors

Nowhere on Wikipedia can you find any information about how the composite video connector relates to actual devices. It's almost solely relevant to consumer video equipment, but this page doesn't cover why it was added. You could maybe check Television, but that has no mention of it either. It's also many dozens of pages long, and mostly focuses on the "tele" part of television, which makes sense since almost all definitions of "television" have to do with the broadcast nature of it. A reader looking for information on the relationship between composite video and television would come here first.

It's impossible to cite any kind of "hard" reference for when composite video was added to TVs. It was not a deliberate decision made by a regulatory or standards body. Manufacturers just chose to do it when they saw the market drifting in the direction of home computers and VCRs. I could cite a book that says this, but that book in turn would be referencing something like Consumer Reports, if it referenced anything at all.

The fact that CR felt an entire half-page should be dedicated to explaining what this strange yellow jack was for, and that their previous years coverage absolutely left it out, is all the proof anyone could ask for that almost nobody had seen one of these before 1984. I don't think this revert made Wikipedia better, since the page still has a significant knowledge gap that has existed for decades and is virtually unfixable by this interpretation of the rules. — Preceding unsigned comment added by 97.113.158.191 (talk) 03:31, 16 July 2018 (UTC)[reply]

Claim: "It's almost solely relevant to consumer video equipment" That's very wrong. You must be completely unaware of the extent of industrial and business video equipment, most of which used comp video (usually on BNC connectors) long before those connectors started appearing on TVs. Heck, even a lot of broadcast/studio video gear, prior to HD, used composite video connections too. (Including "quad" VTRs and all of the associated switchers, etc., of that era.)

You can find history on the "RCA" connector at RCA connector.

Lots of things that would add arguably useful information to Wikipedia articles are precluded by the rules. Another good rule, btw, is to sign your talk page posts. Jeh (talk) 01:08, 18 July 2018 (UTC)[reply]

@@ Line 98: / Line 98: @@
 The fact that CR felt an entire half-page should be dedicated to explaining what this strange yellow jack was for, and that their previous years coverage absolutely left it out, is all the proof anyone could ask for that almost nobody had seen one of these before 1984. I don't think this revert made Wikipedia better, since the page still has a significant knowledge gap that has existed for decades and is virtually unfixable by this interpretation of the rules.  <!-- Template:Unsigned IP --><small class="autosigned">—&nbsp;Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[Special:Contributions/97.113.158.191|97.113.158.191]] ([[User talk:97.113.158.191#top|talk]]) 03:31, 16 July 2018 (UTC)</small> <!--Autosigned by SineBot-->
-: Claim: ''"It's almost solely relevant to consumer video equipment"'' That's very wrong. You must be completely unaware of the extent of industrial and business video equipment, most of which used comp video (usually on BNC connectors) long before those connectors started appearing on TVs. Heck, even a lot of broadcast/studio video gear, prior to HD, used composite video connections too, and prior to color, ALL of it did.
+: Claim: ''"It's almost solely relevant to consumer video equipment"'' That's very wrong. You must be completely unaware of the extent of industrial and business video equipment, most of which used comp video (usually on BNC connectors) long before those connectors started appearing on TVs. Heck, even a lot of broadcast/studio video gear, prior to HD, used composite video connections too. (Including "quad" VTRs and all of the associated switchers, etc., of that era.)
+: You can find history on the "RCA" connector at [[RCA connector]].
 : Lots of things that would  add arguably useful information to Wikipedia articles are precluded by the rules. Another good rule, btw, is to sign your talk page posts. [[User:Jeh|Jeh]] ([[User talk:Jeh|talk]]) 01:08, 18 July 2018 (UTC)