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#61
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![]() Over here in the U.S., on this board, someone said they ran a ATSC digital converter on an old 441 line system (we briefly used 441 lines before our NTSC 525 line standard) set and it does work. I know on my old black and white Sony, the picture is very crisp when I know they are sending an HDTV picture down the pike, usually NBC shows the Olympic trials in high def. I know it isn't true high def, but still, you can see the better picture quality.
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Mom (1938 - 2013) - RIP, I miss you Spunky, (1999 - 2016) - RIP, pretty girl! Rascal, (2007 - 2021) RIP, miss you very much |
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#62
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#63
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Good Day NowhereMan 1966,
Thanks! for your post. You wrote: "I would have loved to see the 819 line standard, it is really high definition". Well, yes and no: i remember seing 875-900 test pattern black/white bars resolved with clear separation on my Grandma's TV in 1959. The French 819 channel (see table below) had a 10.00 MHz video bandwith allocation, but the 4" then 3.5" Image Orthicon camera tubes were not capable of fully using the available bandwith. Also wide video bandwith was(is) expensive to attain in consumer TVs, so only the best really did justice to the system. Still, a live camera picture showing 819 in the late 50s was quite a jaw-dropping experience when compared to 405 (UK) & 441 (vintage French). "I've heard they experimented with color in 819 and IIRC, I think that color system was used for medical schools in their teaching due to the high definition picture but that's what I heard 20 years ago". To my knowledge, Nope! Sorry! Urban Legend. What was used, was a 625 derivation of CBS field-Sequential indeed sold for CCTV filming of operations to med students in hospitals. The Paris Science Museum "The Palace of Discovery" had a color TV demo display showing a field sequential Thomson Vidicon camera on 3 modified RCA 21" monitors + a vertically-mounted 21" RCA color tube showing the various components. The demo ran from 1961-1968. Color TV started here in Oct 1967. Recently (2 years ago) myself and a friend had to privilege to visit the Museum's storage warehouse and took pictures of a complete 1948 CBS system including a color camera + a big + small monitor. This is the last remaining complete CBS system at a single site. see my pictures here on the ETF site: http://www.earlytelevision.org/cnam.html "I know it use a lot of bandwidth but the 819 line picture must have been awesome to look at". RF Channel total width was 14.00 MHz of which 10.00 MHz dedicated to video. "I'm glad at least we have converters to keep our old TV's running for our ATSC standard and your DVB standard. One, I'm too poor to get a new TV, I'm looking for more steady work so the 1982 Zenith model that we've been using for over 25 years will have to do." Keep it running! it's better than all the Chinese junk! "Over here in the U.S., on this board, someone said they ran a ATSC digital converter on an old 441 line system (we briefly used 441 lines before our NTSC 525 line standard) set and it does work. I know on my old black and white Sony, the picture is very crisp when I know they are sending an HDTV picture down the pike, usually NBC shows the Olympic trials in high def. I know it isn't true high def, but still, you can see the better picture quality." I worked 25 years in Broadcast TV. I saw the first 1125/60 analogue pictures at NAB in 1985, then later at a customer's in Paris: TV pioneer David Niles. The pictures were jaw-dropping awesome on a 27" Sony 300 lb, 50K$ CRT Trinitron monitor. You could clearly see the fuzz on the upper lip of a blonde female anchorwoman, filmed 10 feet away. Sorry to say, 1080/i/p is nice but no match for what i saw 23 years ago. I suspect that the camera-fresh signal is OK but that the transmission compression imposed for economic reasons just ruins the signal, what a shame ! Just my 2 cents... HD in Europe: Over here, we have DVB-T (Digital Video Broadcasting-Terrestrial) a pan-European union Digital MPEG-2 625/50 color system. The next step, starting in oct here will be HD DVB-T using MPEG-4 compression, i.e. same RF bandwith, but HD. DVB-S (satellite) is already up & running. UK Sat TV behemoth Sky-TV (8 million subscribers in the UK alone) already has 12 full HD channels running 24/7. What's nice here is that HD channels are full HD 1080i all the time, no "variable geometry" depending on the content (show, movie, sports,advertising, ...) Best Regards jhalphen Paris/France |
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#64
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Wow, so much there, it's tough to cover it all. I know here in the U.S., our ATSC uses MPEG-2 compression. I'd like to see the old analogue 1125 line system, I think it was developed in Japan and was considered to be used here. I'm kind of curious on how sports will look on the HDTV system with compression and all, so far, it seems like it works well on NASCAR (stock car, well used to be) races plus it seems hockey does OK. I'm curious on how it will be when the Olympics come on and when our NFL season starts.
HDTV, I noticed a little more "blocking" from weak signals in the summer but we do have trees in the backyard and we have been having storms with a lot of wind lately. I've seen an article from the early 1950's about the comparison between the 405 line British and 819 line French standards showing a grumpy British guy watching a terrible picture while a happy French guy was watching a great picture. Well, let's face it, the 405 system was developed in the mid-1930's, the 819 line was developed during and just after World War II. I think during World War II the Germans and the Vichy French developed a 1050 line system too. I haven't had much experience in seeing 720 or 1080 line HD pictures although on my old sets, I can tell they are of higher quality. I have three DTV boxes, my aunt didn't need her second one so she gave it to me. I have one hooked up to a 1982 Zenith console, 25 inch, the picture is good as the day we got it over 25 years ago although when the picture tube was tested in 1999, it was showing its age a little. Well, it does take a minute to warm up where it used to take 15 seconds, but it is still good and I'm willing to put up with that. I think because we keep the brightness down, our tubes last a lot longer, Mom hates it when a TV picture is too bright or the contrast is way up too high plus she likes the consoles as I do. The Zenith does show her age a little from time to time so when she acts up, we have a 1998 19 inch BPC TV, also a Zenith ready to go and we give the old one a rest. My other setup is an ATSC box driving a Commodore 1702 computer monitor, my room TV and in the computer room, an ATSC box hooked up to a 1964? Sony B&W set. I can't get used to TV's being flat pictures, I like the old consoles.
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Mom (1938 - 2013) - RIP, I miss you Spunky, (1999 - 2016) - RIP, pretty girl! Rascal, (2007 - 2021) RIP, miss you very much |
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#65
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I can tell you right now that compression artifacts are noticable on 1080i and 720p HD channels, including sports.
I watch these channels on a 19" computer monitor running at 1024x768. The quality is comparable to, or maybe even a bit better then DVD, however, when I look for them, I find the compression artifacts. They're not terrible, but they can be seen, even on my monitor. An 1125 line analog system?! Hot damn would I like to see that! |
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#66
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Imagine if you will; you take an 8x8 block of pixels, scan them and compute a couple of numbers, thenn the receiver gets to reconstruct that block. Oversimplification if you will but that roughly covers what MPEG2 is doing. Then it is playing with your ears trying to send 5.1 sound when all you wanted was stereo.
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![]() Some people are like Slinkies, not really good for anything. They do bring a smile to your face when you push them down the stairs. |
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#67
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#68
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BTW, welcome aboard!
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Mom (1938 - 2013) - RIP, I miss you Spunky, (1999 - 2016) - RIP, pretty girl! Rascal, (2007 - 2021) RIP, miss you very much |
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#69
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was true, but you say more HR DIEMEN Spanish closed the plant where product line transformer for tv set (EHT) and PTC (for the purity of crt) are no longer manufactured, to say nothing of spare parts for the vcr. we are forced to fit from something very biggest of us,
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#70
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About 5 years ago, a local TV repair shop, with a Zenith TV sign bearing the shop's name, was destroyed in a building fire. seems a plumber fixing a pipe (soldering it with a blow torch) inadvertently torched the place. Building was totaled, and was rebuilt. The TV repair shop owner must have taken the insurance money and decided that it wasn't worth the trouble to re-open. Probably he wasn't making enough money running it.
Place had a few 80's and 90's TV sets displayed in the front window. Was going to pay the place a visit, but never got around to it when it was open...
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#71
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JHalphen, when you say you get obsolete ICs from China do they actualy work? I am desperate for an OKI MSM58141RS and cant find one anywhere.
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![]() Some people are like Slinkies, not really good for anything. They do bring a smile to your face when you push them down the stairs. |
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#72
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I don't think Diemen did a smart move to discontinue their flyback production, since there are still A LOT of CRT sets in regular use here in europe, and the digital switchover won't happen before 2012
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#73
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Last edited by andy; 12-07-2021 at 05:04 PM. |
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#74
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Well, they probably still have trainloads of NOS flybacks left in their warehouses!
I recently got 6 large boxes full of NOS flybacks for tube-based Italian B/W sets for free from a local repair shop! |
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#75
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