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  #31  
Old 07-26-2012, 12:53 PM
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Cleveland's WKYC-TV (NBC affiliate) had a color-wedge test pattern in the '60s-'70s that showed its city of license in the same place the NC station's did. The Cleveland station's pattern also showed, briefly (for only a short time, IIRC), the old NBC "snake" logo in one corner, with the city of license appearing elsewhere on the pattern; I forget where.

Local TV stations and networks still use a color bar test chart, with the ID or the words "please stand by" in the center of it, when there are technical problems (in fact, a channel that no longer transmits an analog signal on the cable system here shows only a color test chart on that channel, with no ID or anything else), but the circular and box-shaped test patterns (the latter appearing on at least two UHF TV stations in Cleveland and likely in other cities, when US and Canadian TV stations still signed off for the night and on again the next morning) have gone the way of analog NTSC TV and reel-to-reel video tape recorders.
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  #32  
Old 07-26-2012, 10:10 PM
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The subject of patterns is one of the most fun because they are both entertaining, weird, and useful. There is a whole slew of unusual patterns on Laserdisc test discs and not all are static. Like TV patterns, many of those are made for using a scope to check signals in the equipment and not for monitor candy.

Over the years I have collected a few commercial pattern generators and have gotten rid of the Heathkits and such for the most part. I use a Tektronix 1400 series or Leitch DTG-1010 generator in the lab, or a portable Sony DSG-10 hand-held in the house if I am lazy (but it is missing the blue filter card, believe that is what goes in the slot). Sometimes I use a home made monochrome multiburst generator. I didn't build it but it came from an unidentified TV station's basement. I suppose an engineer built it up, perhaps before color as it is all transistors no IC, and it makes no color burst so it was likely intended to tweak up high resolution monochrome studio monitors. It's all perf-boards and hand wired with DYMO strips for labeling. A holy relic I have kept to honor the work of the unknown builder. I also have a couple of B&K flying spot scanners and those are nice because an approximately 4" negative film can be put in, and one could make one's own pattern that way but I have not done it because I don't have any experience with film and printing on transparency sheets has not yielded very good results. (those B&K manuals are on bunkerofdoom.com)

If there is a good sharp image of the Indian head pattern, I'd sure like to see it, seriously have a copy to digitize.

In Dallas, it's not easy to find a test pattern and most of the TV stations never seem to go off the air.

Instead they put on these awful droning or screaming, and lying infomercials all night, and even those sometimes have commercials in them. Who are the many brainwashed viewers hurrying to call and get that weight loss and mens' function pills combo, with the hair tonic thrown in? But wait, if you order in the next 10 minutes we'll throw in these love pills for the wife ! Now due to high call volumes, we're overwhelmed and only people with last names from A-J can call now, all others must call tomorrow! I guarantee that makes the K-Z cattle virtually leap to the phones!
I pity those TV-holics that work days and have only those things to watch.

Don't even have the decency to show old movies and play the National Anthem at some point each 24 hours. I miss that. I imagine they would play the Anthem if someone would buy the airtime. here's a plan. pay it for a couple months, then end the contract. people will call in angry about it being stopped. Would they dare to say they had to be -paid- to do it?
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Last edited by Opcom; 07-26-2012 at 10:13 PM.
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  #33  
Old 07-28-2012, 11:23 AM
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One of the TV camera collectors not often seen on VK sells them on his website, apparently saved from a dumpster by a worker who was demolishing the building they were in...

http://pharis-video.com/p5013.htm

No affiliation here, but I do have Delaware Native tribe ancestors from NJ. Wondered if one wandered into the RCA building one day...

Last edited by Einar72; 07-28-2012 at 11:26 AM.
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  #34  
Old 07-28-2012, 04:51 PM
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Television here in northeastern Ohio is also non-stop, with no Cleveland station signing off for any reason except technical problems. I used to get up a five a. m. just to watch the test patterns from the three (at the time, '60s-'70s and until all TV here went full-time) network affiliates before they signed on. It was also interesting to watch after the local stations had signed off; occasionally I'd see a test pattern from a distant station, usually on channel 3 or 5. I live in the Great Lakes region near Michigan and southwestern Ontario, and I would sometimes see actual programming from station WNEM-TV in Saginaw on channel 5 after Cleveland's ABC affiliate had called it quits for the night. I'd also see programs, and occasionally a test pattern, from channel 12 in Erie, Pennsylvania, channel 10 in London, Ontario, channels 11 and 13 in Toledo, Ohio, channels 2, 4 and 7 from Detroit, and a host of UHF station patterns as well.

I wonder about those late-night infomercials too. Not that they bother me (I often stay up late at night and will usually watch a DVD if there is nothing to interest me on standard broadcast TV), but I do think they waste the stations' RF and DC power, not to mention raising the question in my mind of who actually watches these things at the unearthly hours at which they air. The TV networks and local stations are trying to gain early-morning viewers by airing newscasts at 4:30 a. m., but sometimes I wonder who is actually up watching TV at that hour; five or six a.m. makes more sense to me. The only people I can think of who might watch those 4:30 newscasts would be those who begin their work day unusually early, say at five or six in the morning.

I have heard that some infomercials, known as "paid" programs or advertisements, can and do actually generate revenue for TV stations whether or not anyone watches them. I cannot for the life of me see how that is possible. These things cannot, to my way of thinking, raise one red cent if no one is watching. One of these days I'd like to find out just how paid programs/advertisements work to a TV station's advantage, and whether they are really worth the time and money the stations spend to put them on at hours when most folks are sound asleep.
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Last edited by Jeffhs; 07-28-2012 at 10:12 PM.
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  #35  
Old 08-25-2012, 03:22 AM
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cbenham cbenham is offline
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Quote:
Originally Posted by Celt View Post
I always liked this one which I refer to as "Old boring B&W movie about Indians".
Here's my favorite test pattern...
Cliff
Attached Images
File Type: jpg CBS Color Test Pattern .jpg (49.4 KB, 48 views)
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  #36  
Old 10-09-2012, 11:34 PM
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Google "TV Test Pattern" in their "images" area. There are a ton of them available as jpeg's. If you want to actually use one to set up your old video equipment look for a Micca Digital Media Player at Amazon.com http://www.amazon.com/Micca-MPlay-Di...keywords=micca or eleswhere. You can save the test pattern on a regular SD memory card, and the Micca player will turn it into composite video. The good news is the player is less than $30. I have one on my work bench and have a variety of test patterns and color bars stored on it. I love it.
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  #37  
Old 12-20-2015, 10:20 PM
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As I'd noted in earlier posts, the color circular test pattern design originally had two variations, coded by region as per the order of a diagonal black/white wedge at the bottom of the outer lower right quadrant. TP's with this layout:



were for stations east of the Mississippi with 'W' calls; three stations were confirmed to use it - WIBF (later WTAF and now WTXF) Channel 29 in Philadelphia, PA; WFLD Channel 32 in Chicago, IL; and WNDT (now WNET) Channel 13 in Newark, NJ / New York City (the last actually confirmed to be color). And as laid out here:



was for west of the Mississippi with 'K' calls. Only one station, to date, has been confirmed to use it, and then with a B&W print: KAET (Channel 8) in Phoenix, AZ.

My question is, how many "old-timers" on this forum remember either layout, and who else would've used either prior to the wedges at bottom right being eliminated? Certainly those stations weren't the only ones . . . ?
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  #38  
Old 02-18-2016, 10:29 PM
centralradio centralradio is offline
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Wow .I remember the days of the late night test patterns.Thanks Telecruiser for the info on the video playback device .I've been looking for something like that for years.
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  #39  
Old 02-19-2016, 09:47 AM
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CoogarXR CoogarXR is offline
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I have a small SD-Card/CF video player (it's about the size of a cassette tape case). I have an SD card with movies on it for long-run testing, and I have an SD card with test pattern JPGs (it does a slideshow). It has composite+audio and VGA outputs. It's pretty handy, and tiny on the bench.

I also have a SD card with a single solid white image. It's good for flushing screen burn-in on plasma TVs.
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  #40  
Old 06-16-2016, 10:28 PM
W.B. W.B. is offline
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Quote:
Originally Posted by old_tv_nut View Post
OK, this is a very old concept, but here goes:

There are 525 total lines, but only 483 active lines due to vertical blanking. Let's just call it 480 for rough calculation (which also matches a common computer image format).
Because the lines sample the picture vertically (just like the rows of pixels in a digital picture), they cannot provide a full 480 lines of resolution for ordinary pictures - they could only do that if the picture details happened to line up exactly with the line structure. The ratio of practical viewable resolution is called the "Kell factor" after Ray Kell, who published the original research in 1934. There is an additional factor due to interlace causing interline flicker - how strong this is depends on the observer and the amount of detail contrast in the image. The first NTSC (1941) adopted an over-all factor of 0.7 for the achievable resolution compared to the number of active lines. Along with this they specified a combination of baseband video signal bandwidth (4.2 MHz) and active scan lines (486) that would give equal resolution per picture height vertically and horizontally, and also fit in a 6 MHz channel using vestigial sideband modulation and including a sound carrier. 480x0.7 = ~330, the accepted usable resolution - your mileage may vary, and there have been a lot of useless arguments over the years as to whether the useful vertical resolution number is exactly correct.

A few of the active lines were later devoted to other things like test signals, data, and closed captions, leaving 483 containing picture.
A video transfer firm that deals with 2" quad transfers, has shown some screengrabs in full D1 720 x 486 frame - and only 484 lines were actually used, with the top two lines (lines 21 and 283) unused, and those being used consisting of 22 - 263 and 284 - 525. Apparently, 483 was in the analogue realm in that sense, and thus by digital frame grabs one can see by each "half-line," 484 lines in essence.
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  #41  
Old 07-26-2016, 01:49 AM
centralradio centralradio is offline
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Quote:
Originally Posted by CoogarXR View Post
I have a small SD-Card/CF video player (it's about the size of a cassette tape case). I have an SD card with movies on it for long-run testing, and I have an SD card with test pattern JPGs (it does a slideshow). It has composite+audio and VGA outputs. It's pretty handy, and tiny on the bench.

I also have a SD card with a single solid white image. It's good for flushing screen burn-in on plasma TVs.
Not to skew this topic off course .Whats the name of the SD-Card/CF video player you are using.I've been looking for one for a while now.Thanks.
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  #42  
Old 07-26-2016, 10:42 PM
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In the early days it was a VHS tape I recorded a test pattern to using a VGA to composite adapter.
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  #43  
Old 07-27-2016, 08:21 AM
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CoogarXR CoogarXR is offline
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Quote:
Originally Posted by centralradio View Post
Not to skew this topic off course .Whats the name of the SD-Card/CF video player you are using.I've been looking for one for a while now.Thanks.
My work area is under construction right now, all my equipment is buried, lol. But I know I have two of them, one is a no-name chinese unit, it has a remote and everything. The other one is white, it has a brand name, but I can't remember for the life of me what it is...

I looked on ebay and google, of course I can't find a picture of one like mine. But if you search for "sd cf media player" there are a ton of options out there. Some have HDMI. I wish mine did, I might have to upgrade!
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  #44  
Old 07-28-2016, 01:19 AM
centralradio centralradio is offline
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Quote:
Originally Posted by CoogarXR View Post
My work area is under construction right now, all my equipment is buried, lol. But I know I have two of them, one is a no-name chinese unit, it has a remote and everything. The other one is white, it has a brand name, but I can't remember for the life of me what it is...

I looked on ebay and google, of course I can't find a picture of one like mine. But if you search for "sd cf media player" there are a ton of options out there. Some have HDMI. I wish mine did, I might have to upgrade!
Thanks .I will google it out.
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