Talk:Analog television

message: I got into a discussion and some persisted that Ch 7# where the highest analog channels.  I thought this was b/c that is all they have ever encountered.  Since my TV goes up to 120 or beyond for analog stations.  So what are the possible channels for analog TV in the US and elsewhere.  Both Broadcast / and Cable etc. EDIT
I guess this site says Broadcast is 2 - 83. http://electronics.howstuffworks.com/dtv3.htm
How about cable though can it go all the way to 12#?  TY
: Hello, as a Radio Amatuer with my own station, and speaking as an electronics engineer in T.V. and Radio since 1963, I can only provide the information for the historical U.K. channels. In the 1950s 405 line T.V. transmission were made on V.H.F Band 1, it was 5 channels only, (all B.B.C.), then in the 60s Band 3 was used for independant commercial stations (ITV) - channels 6 -13. Band 2 was designated for use by F.M. Radio stations. In the mid 60s, a new system of 625 line colour transmissions was introduced on the U.H.F band. This band had channel numbers designated for 21 - 68 (for use by all companies). Digital multiplexed transmission technology allows a greater number of channels to occupy the same analogue channel space. So, I guess as time goes on and different multiplexed modes evolve, more and more "channels" will appear in the same frequency allocation. The total number of broadcast "channels" (frequency allocation) is set by international agreement. This is done to minimise the effect of co-channel interference between geographical areas (and countries). see OFCOM in the U.K. for band plan information and allocated frequencies (channels) for broadcast stations. I have my own band plan of allocated frequencies (channels) I can broadcast on using different modes (T.V., CW etc). Hope this helps.Francis E Williams (talk) 17:43, 23 November 2010 (UTC)
replies: text: It used to be that US channels went 2 to 83, for 82 channels. VHF, 2 to 13, is 54MHz to 216MHz, with some holes, such as for FM, and other radio systems. Then UHF from 470MHz to 890MHz for 70 channels 6MHz wide. Note the big space between 216MHz and 470MHz where no TV channels exist. Cable can use those frequencies, as long as they don't interfere with other uses. Somewhere in Wikipedia there should be a table of assignments for analog cable TV channels. In any case (470MHz-216MHz)/6MHz allows for 42 more channels, so up to about 125 for the usual analog cable system.  Gah4 (talk) 15:35, 25 March 2020 (UTC)
thread_title:   Could someone add the maximum number of Analog channels? 

message: Does this article seem biased towards analog TV to anyone else? -216.138.38.86 15:45, 26 January 2007 (UTC)
replies: text: The point is that this artcile is about analogue television. The same situation can, for example, be observed with MP3, while Ogg Vorbis is the better format (because it's free). -Mardus 06:12, 10 March 2007 (UTC)
replies: text: Mardus, of course it is OK for an article to talk mostly about the subject and briefly cover the related topics.  However, the section "Comparison of analog and digital television" should really be called "Advantages of analog over digital television".  If a page is going to compare the subject with related subjects, it should compare them in a fair and balanced way.  The reason everywhere is changing to digital is that it is superior to analog overall.  The only advantage of digital listed by the editor of this section is the fact that it can deal with a low power signal without breaking up.  This section is definitely a one sided view. Hpesoj00 13:37, 15 March 2007 (UTC)
replies: text: I do concur with this. One disadvantage of digital television is that older TV equipment that still works cannot be used to receive the signal. But there should therefore be more advantages listed, because I don't feel that just one advantage is enough reason to switch. -Mardus 17:35, 16 March 2007 (UTC)

text: Hate to disagree with you Hpesoj00, but the driving forces to DTV includes the re-allocation of the frequencies to be used for other communications uses and addition of additional channels and ancillary services that can be transmitted by the broadcaster.  HiDef HDTV development was started to increase the quality of the broadcast image to the viewer.  After General Instrument, Inc. found a way to use the rapidly evolving digital technology to pack more information (pixels, bits...) into the same bandwidth of the existing channels some additional "features" came to light at the expense of being compatible with the existing television receivers.  The broadcaster could transmit one really high quality image...or several with lower quality. Some even lower than current analog.  Deliver several poor quality programs when the initial promise/goal was for high quality images.  And Digital DTV can add additional communications data services not related to pictures or sound.  The idea of "Channel 4" getting licensed to broadcast several more channels seems at the first glance to be a windfall for the broadcaster.  Sadly, getting four times as many channels in a community will not generate four times the ad revenue as the population in the community stays fixed. (duh) Currently the broadcasters are running both analog and digital on different frequencies.  Waste of bandwidth and electricity.  Digital TV can offer images vastly superior images, but the quality can be reduced at will leading to annoying motion artifacts, quantizing/contouring artifacts noticeable in dark scenes, and image breakup should the electronics simply not be able to keep up with the data.  In the end I have to agree that the page seems to tilted to being a proponent of the analog system and perhaps a POV issue could be resolved with more detailed discussion.  OldZeb 06:26, 22 March 2007 (UTC)
replies: text: I guess you were disagreeing with "digital is better than analog overall", I suppose it depends who you ask, it is a rather subjective topic.  The section seems to have been balanced out a bit better now, but the information is still not presented in a very well organized manner.  I may attempt to neaten it up if I find myself with nothing to do, but I am no master of the subject so maybe it should be better done by someone who knows what they are talking about. Hpesoj00 10:55, 23 March 2007 (UTC)
thread_title:  POV 

message: The http://www.ee.washington.edu/conselec/CE/kuhn/ntsc/95x4.htm link is broken. It should be removed or someone should find where it has been moved to. —The preceding unsigned comment was added by 91.120.69.76 (talk) 09:54, 26 February 2007 (UTC)
thread_title:  Broken link 

message: Why bother? The full resolution of 525 lines (4 Mhz) on NTSC equipement has never been realized.
: Well, yes it has.  Many consumer receivers made in the 1990's have comb filters, some 3-D with motion compensation.  A 1979 model Magnavox came with a comb filter. Ohgddfp (talk) 22:10, 27 April 2014 (UTC)
replies: text: The NTSC wrote the specs for analog broadcasting.  So genuine NTSC equipment is actually about 340 TV lines of horizontal resolution, equivalent to 449 rectangular pixels horizontally, max. Ohgddfp (talk) 22:10, 27 April 2014 (UTC)

text: 450 what?  You talking horizontal or vertical? Ohgddfp (talk) 22:10, 27 April 2014 (UTC)

text: Actually gave 340 TV lines of horizontal resolution, equivalent to 449 horizontal pixels at full contrast.  This is the legal limit, imposed by the FCC. (code of federal regulations, title 47, part 73, chapter 682, "Transmission standards".  These are the standards, written by the NTSC and accepted by the FCC, for the specific purpose of being included in the federal regulations. Ohgddfp (talk) 16:35, 27 April 2014 (UTC)

text: One DTV channel can deliver two 4:3 640x480 resolution channels (one main and one sub) each of which is better quality than NTSC. Ohgddfp (talk) 16:35, 27 April 2014 (UTC)

text: DTV delivers a payload of slightly more than 19 million bytes per second. Ohgddfp (talk) 16:35, 27 April 2014 (UTC)
thread_title:  Comparison of analog and digital television 

message: Too many people here seem to base this article's 'facts' on what they see at home, and even drag old VHS recordings and Big Ben in to prove points. There are quite a few very subjective statements made, which have nothing to do with the true quality of digital (or analog) TV. These WK editors are blaming the Titanic for the ice berg.
Many cable and satellite stations will (re)compress digital video signals to be able to carry more data (= channels) on the same bandwidth. This obviously reduces picture quality. However, that doesn't mean digital TV is poor. It only is when it is mis-used, re-compressed, improperly transported, etc, etc, like in the example above. Just like analog signals can be distorted. The quality of digital TV is better than that of analog. There's simply no denying that. However, you can't properly judge it by watching your TV at home. 
Go to a professional digital edit suite, watch the edited master on a decent studio monitor, and compare it to an analog edited master. Then you can judge what you're talking about. Jerky movement? Nonsense. Poor lip-sync? Blame your local distributor. Paint-by-numbers? Bad re-compression.
I've edited digital broadcast video for national TV for almost a decade. Do you really think we'd buy all that expensive studio hardware if digital is as bad as Wikipedia claims it is? Dudes, please... That paragraph should go. Rien Post 23:57, 6 May 2007 (UTC)
replies: text: This section is virtually complete and utter nonsense. It needs scrapping and starting again. I could go through point by point but I think I have issues with everything that is currently written. Even where it says analogue transmissions are poorer than they used to be.  ... and how on Earth can you compare VHS recordings and a broadcast signal? the quality of most VHS recordings is frankly ****. I'm not sure whether the fact that broadcasters have been sourcing material digitally for years would also have an affect on the ability to compare, in most cases analogue for some time has been a retransmission of the digitally sourced signal.  AFAICT audio has been digital to some degree since the advent of NICAM stereo in the 80s.  The claim that roof top aerials are worn out is also particular to the person - in the UK the reverse is likely to be true as many people have needed to buy new aerials to receive the comparitively weak DTT signals that Freeview is broadcast on (IIRC about 1% of the power of the analogue signal).  This measure is precisely so the digital broadcasts dont interfere with the less robust analouge signal  Pit-yacker 17:38, 7 May 2007 (UTC)
replies: text: in most cases analogue for some time has been a retransmission of the digitally sourced signal. True, very true. Now is somebody going to delete that paragraph for good or are we editing and reverting this silly thing until the end of time? Rien Post 20:56, 9 May 2007 (UTC)
thread_title:  Comparison of analog and digital television (2) 

message: Sorry for making so many edits, but I think I got this thing a bit cleared up. Some of the information is clearly made up by the person who edited it before me, but I can't find anything proving or disproving it. As for the ammount of 'citations needed', I cleared a few of them out and added a bit more info... The problem with some of the info in there is that there are absolutely no references on the internet, anywhere, it is just the way it's always been so no one talks about it. W/e, I'm done caring :P —The preceding unsigned comment was added by Gripen40k (talk • contribs) 17:39, 15 May 2007 (UTC)
thread_title:  Ok... Cleared up a few things 

message: Can analog television owners still watch satellite and cable broadcasts with out any difficulty?  Does the change only effect televisions recieving network broadcasting?Mustang6172 22:01, 28 June 2007 (UTC)
thread_title: Clarification needed

message: I've removed the analog television reference links from the University of Washington's College of Engineering as they no longer existed.  Someone attempted to retrieve them from Google's cache, but the links were found to be dead when I inspected them last.  Because of the fact, can anyone please cite proper sources on analog television technology that are static, no pun intended, links to information that will not be moved or removed. --Mnemnoch 07:21, 29 July 2007 (UTC)
replies: text: Done!  OldZeb (talk) 22:36, 3 October 2008 (UTC)
thread_title:  Analog television technology references needed 

message: How will the advent of digital TV affect channel allocations of stations already on air? WAVY 10 19:24, 24 September 2007 (UTC)
thread_title:  Channel allocation 

message: Please take a look at Talk:Technology of television. I'd like to have some discussion about possible reorganisation of the many television technology pages there are floating about. 
IanHarvey (talk) 10:23, 22 January 2008 (UTC)
thread_title:  Merging/reorganising with other TV pages? 

message: Please see Talk:Technology_of_television#Proposed_Changes which I am going to implement shortly if no-one speaks up.  IanHarvey (talk) 12:42, 20 February 2008 (UTC)
thread_title: Proposals

message: Analog televisions have historical significance far beyond digital, to be honest.
Some of the most important events of the Twentieth Century were on the television. The only thing that picked those things up were Analog TV sets. The Apollo moon landing and the Nixon election campaign were both on Analog TV. They had three channels with that thing (plus local stations), and for about forty to sixty years, they were happy.
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As we all know, Analog is going to be banned this June, forcing all analog owners to buy a government conversion unit.
This article should not be merged because it is a key part of the television's history. It is a highly notable article. I've seen mergers go through before, most of the information is cut out and lost to readers.
The price of those converters are fifty dollars at a Radio Shack, and they've got coupons at the Digital Transition website. These can send the price way down.
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However, analog television holds history because my father, grandfather, and ancestors watched with it, and it's one thing I, as a fifteen-year-old teenager, do not wish to see lost to history.
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My grandfather jokes about some of my generation "thinking that food comes from the grocery store,unaware of cows and farms and such". I always found that funny, but he may have a point.
As such, this is a really good article, written quite well. It is indeed notable, as aforementioned, because it was the only thing until the eighties. Cable came after. It's actually pretty much forgotton, with antennas and such being relics. This article is notable, and even historically significant.
Three channels! I don't know how I could have handled that television. My ancestors did, and that is intriging to me. This article deserves to stay for its significance, not just for me, but for all of the old people who come here.
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When I see something I love on Wikipedia (turtles, The Slowskys, ect. ect.), it puts such a smile on my face. I think all viewers, young and old, deserve that happiness of seeing something important to them sitting as an article here on the Wikipedia. It's pleasing to me.
I read to my grandfather the Super Bowl history article. He recalled it all, the article as accurate as his memory. It was an enjoyable time.
:Comment Support merge with How television works, duplicate material, keep "Analog television" as title.  Drawn Some (talk) 13:54, 24 May 2009 (UTC)
thread_title:  Merger with another Article?! I think not! 

message: These are 1-paragraph context-less stubs that would be better off merged here. There's a good diagram showing the definition and the cnocepts have little meaning outside of the context of a television scan line. Similarly, the synchronization material needs to be better integrated, since it is largely repetitive. --Wtshymanski (talk) 21:46, 6 October 2010 (UTC)
replies: text: I have been working on these recently and was going to expand them. But if you want to merge them, then it's fine by me. It's not that important to me. -      Hydroxonium (talk) 05:01, 8 October 2010 (UTC)
replies: text:  The more I look at this article, the more work it needs.  Where's the *transmitter* end?  Never mind the microseconds, etc. but we don't talk about the limitations and defects of analog transmissions, and *why* they are being phased out. Typical Wikipedia myopia...list all the engine model numbers but never explain *why* you need a train. --Wtshymanski (talk) 17:00, 12 October 2010 (UTC)

text: Isn't that kind of the point?  Analog television is the broadcasting of analog TV signals, which have front porch, etc. components. Everything describing an analog TV signal should be in one place and not scattered in context-less fragments. (This also needs more references.) --Wtshymanski (talk) 14:13, 9 November 2010 (UTC)
replies: text: I agrre to oppose the merger, on the basis that the control signals required for digital display of coded data are still required, and are part of the current digital transmission signals. These still control the positioning of scan lines on the display. Try this link, you`ll have to buy the document to view the content about front and back porch detail.Francis E Williams (talk) 21:04, 23 November 2010 (UTC)
thread_title: Merge front porch, back porch

message: I trained in, and qualified in Television and Electronics. I worked with analogue (English) /analog (Amaerican) television technology since 1963. From days of valve projection single channel receivers to todays flat screen LED (not LCD) displays. (Have 42" Panasonic LED TV.). I`m a bit of a "techie" in many fields...Plus .. I`m retired, makes me a good candidate to spend this winter exercising the dying "grey cells", (and the failing eyes),  to add the refs. and my knowledge to this fine article.Francis E Williams (talk) 21:19, 23 November 2010 (UTC)
thread_title: Citations / References / External links

message: I have at last stopped being a "Techie" based editor with this article. I now think the article should focus more on the differences in image processing aspects of analog transmissions, rather than the technological changes that have taken place with the hardware. Some historical hardware detail has to be included of course, to make the article more complete, more accurate, and informative to the technical reader. Should this be the way forward with this article, if so what do you think? I quote this rather observant editors comment, "after a few years of accretion someone has to go through and bubble-sort everything to put it into some logical sequence".Francis E Williams (talk) 22:00, 25 November 2010 (UTC)
replies: text: Yes, mostly.  About hardware.  Hardware to the extent that it informs how the analog video signal format came to be.  Limitations and expense of receiver hardware had a huge effect on the engineering choices of the analog signal format particulars. Ohgddfp (talk) 00:50, 3 May 2014 (UTC)
thread_title: Article layout and readable continuity

message: Can there be a section discussing the problems with red over-saturation in NTSC video? I know that intense red is not handled well, and can lead to smearing/bleeding of the red across the scan line. There is probably a technical explanation for it, but I am not enough of an expert to talk about it. DMahalko (talk) 18:32, 22 December 2010 (UTC)
replies: text: In some scenes with red lettering, for example, red can seem to bleed.  But this is rare.  Red bleeding in general always happens if the receiver saturation knob is set incorrectly high, which is probably where this picture quality complaint comes from. Ohgddfp (talk) 16:58, 27 April 2014 (UTC)
thread_title:  Red over-saturation / bleeding? 

message: This article contradicts the article on Digital television transition. The latter article states that the Netherlands was the first country in Europe to switch to digital television, but this article states that it was 
Luxembourg. ACEOREVIVED (talk) 00:30, 24 February 2012 (UTC)
thread_title: A contradiction

message: In the section, "Color video signal extraction", I would like to see a change to the paragraph that begins with "Instead, the RGB signals are converted into YUV form, where the Y signal represents ...".   The new version I believe clears up some details by using well documented technical facts.  Here's the new version: Ohgddfp (talk) 16:22, 27 April 2014 (UTC)
thread_title:  Color video signal extraction - Edit 

message: About "The carrier is never shut off altogether; this is to ensure that intercarrier sound demodulation can still occur.":  This is a fallacy.  The reality is that not allowing the carrier to go below 15 or 25 percent for the white reference (minimum picture carrier) was being pushed back in 1941 and even earlier.  The Intercarrier sound recovery technique was invented in 1944/1945.  There is an 1948 patent on intercarrier sound.  But this fallacy goes even further.  You don't need an on-air continuous picture carrier to use the intercarrier sound recovery technique.  Let's say reference white was standardized at zero percent carrier.  In a movie about a snow storm, you will have a frequency spectrum that includes the carrier and sidebands.  If inside the receiver the picture carrier is narrow-band filtered to less than 30 Hz, the flywheel effect of the filter would produce a continuous picture carrier at the filter output from the intermittent picture carrier received over the air.  The new continuous picture carrier would then be applied to effect the intercarrier operation, producing a clean 4.5 MHz sound IF.  To fix this in the article, I would simply remove the sentence. Ohgddfp (talk) 21:56, 27 April 2014 (UTC)
thread_title:  Structure of a video signal - Intercarrier - Edit 

message: The very first paragraph has a problematic phrase: "... one in which the information to be transmitted, the brightness and colors of the points in the image and the sound waves of the audio signal are represented by continuous variations of some aspect of the signal; ...".  The problem is that the exact same thing can be said of 8VSB digital television.  On the air, the DTV signal is a continuous-time signal.  But one might say that the DTV signal represents a discrete-time list of values streamed over the air, which it does, and so the continuous-time on-air signal and the discrete-time digital signal inside the digital receiver both represent the same information.  But that doesn't distinguish analog from digital either, because any real analog signal also represents a discrete time list of values, where both discrete-time analog and continuous-time analog represent the exact same information.  To find out what exactly that discrete time list of analog values are, just sample the continuous analog signal.  The result is analog (not digital) samples.
So what makes an analog signal analog?  At any given point in time, an analog signal can take on any one of an infinite number of possible values.
So the sense of the word "continuous" as used in the opening paragraph to mean continuous-time, does not distinguish analog from digital.  Rather, it is "continuous" in a very different sense that makes the difference.  And that requires a different explanation.  The value of each analog sample is continuously variable, meaning that its value is taken from a continuous range of possible values.  That means an analog sample can take on any one of an infinite number of possible values, or the possible value of a single given analog sample is infinitely or continuously variable.  In contrast, a digital sample can be any one of only a limited number of possible values.  
So here is the recommended fix:
Analog (or analogue) television is the analog transmission that involves the broadcasting of encoded analog audio and analog video signal:[1] one in which the information to be transmitted, the brightness and colors of the points in the image and the sound waves of the audio signal are represented by some aspect of the signal; its amplitude, frequency or phase, the values of which, at a given point in time, is any one of an infinite number of possible values. Ohgddfp (talk) 02:28, 29 April 2014 (UTC)
replies: text: Analog doesn't have to do with continuous/discreteness, but with analogness, as in analogy. In the case of video, some property such as voltage, current, density, magnetic field strength, frequency, or probably others, changes in relation to the luminance in the source. Because we live in a quantum world, most of those are actually not continuous, but that isn't important. (Voltage is quantized by the charge on the electron and capacitance of the system.  V=q/C) Consider a text display that is black and white, but no gray. It is discrete, but in an analog system sent as a voltage with two possible values. In the digital case, it is numbers that are transmitted, not voltages or currents. Gah4 (talk) 15:17, 25 March 2020 (UTC)
thread_title:  Analog - what is it? 

message: Wide screen 16:9 aspect ratio CRT-based receivers were available for a while for reception of digital television signals.   So flyback power supply design, which is specific to CRT-based receivers, applies equally to analog and digital.  Since the title of this article is "Analog Television", the reader expects information that is unique to analog.  This section is so long that a link to flyback power supply design by far makes the most sense. I'm planning to move it to the appropriate article. Ohgddfp (talk) 02:22, 30 April 2014 (UTC)
thread_title:  CRT flyback power supply design and operation principles - Doesn't belong here 

message: There is --- maybe in all the english Wikipedia articles ?  --- a confusion between the system of transmission and the color coding.
The official systems of transmission are named : A, B, C, D, E, F, G, H, I, K, K1, L, M and N.  These systems determine the Number of lines, Channel width, Vision bandwidth, vision/sound separation, etc.
The colour coding which may be used of those systems are NTSC, SECAM and PAL.
So, I'm sorry for Wikipedia but this is the official situation.
--AXRL (talk) 14:25, 9 May 2014 (UTC)
thread_title:  CONFUSION BETWEEN "TV SYSTEM" and "COLOR SYSTEM" ! 

message: Just finished skimming the article and I agree that it should remain as a summary of the different types of transmission and reception systems which were in use. That being said, the words Television and TV generally refer to the receiver in American English. Renaming the article to Analog (Analogue) Television Systems would inform both American and Commonwealth English readers that this is a general overview article with links to more in-depth articles.Divercth (talk) 21:35, 29 January 2015 (UTC)
replies: text: This is not supported by WP:TITLE (where parenthetical disambig is allowed after the main title, but not within) nor WP:ENGVAR. It would make for an awkward title. We don't follow this practice for any other articles I'm aware of, like Analog recording, Analog computer, Analog synthesizer, etc. There's already a redirect - "Analogue Television" redirects here. And the redirected term "Analogue television" is bolded in the lede. This is in accordance with WP:ENGVAR. Jeh (talk) 22:20, 29 January 2015 (UTC)
thread_title:  Rename article to Analog (Analogue) Television Systems 

message: The article says: Thus with analog, a moderately weak signal becomes snowy and subject to interference. In contrast, a moderately weak digital television (DTV) signal and a very strong digital signal transmit equal picture quality.  Depending on the definition of moderately, this is true. The problem is that moderately weak might be below the ability to decode, in which case you get nothing, or, more usual, flashing on and off, as it does, and then does not, have a decodable signal. With analog, it gets weaker and snowier. This is well known, and part of come FCC rules, as there are places that had a strong enough analog signal, but too weak in digital. Gah4 (talk) 21:35, 20 May 2020 (UTC)
replies: text: I have improved this. ~Kvng (talk) 13:56, 23 May 2020 (UTC)
thread_title:  moderately? 

message: Quote from article "Horizontal and Vertical Hold controls were rarely used in CRT-based computer monitors", This is patently wrong. Most monitors from a CBM PET to a TRS-80 model 4 to a DEC VT420 to a IBM 5153 monitor, all have both sync controls. Some accessible without removing the case, some only as maintenance controls, but they still had them.  — Preceding unsigned comment added by 192.149.117.67 (talk) 04:44, 31 July 2020 (UTC)
thread_title:  Computer CRTs 

message: The article says: amplitude, phase and frequency.  For US NTSC, video is amplitude and phase, but audio is frequency (FM). That wouldn't be so bad, but the link is to phase and frequency as one article. I believe some system(s) use FM for video, though. Can we have separate links for phase and frequency? Gah4 (talk) 20:51, 6 April 2023 (UTC)
thread_title:  [[amplitude]], [[instantaneous phase and frequency|phase and frequency]]