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Old 12-27-2011, 09:56 AM
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Test pattern?

I have to do a proper linearity adjustment on my '63 Zenith portable, and was wondering how everyone here does theirs? A television analyst, a DVD with a test pattern, SWAG it, or.....?
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Old 12-27-2011, 10:05 AM
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I bought a home theatre setup DVD, which has color bars, cross hatch, dots, etc.

Feed it into a VCR, and then VCR into TV

I don't trust my ancient unrestored TV analyst to have any better linearity than the ancient TV I'm trying to align.
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Old 12-27-2011, 10:08 AM
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I have a color bar generator for sale.
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Old 12-27-2011, 11:29 AM
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Originally Posted by Kamakiri View Post
I have to do a proper linearity adjustment . . . .
You can get a custom DVD created here and the money goes to a good cause:

http://www.earlytelevision.org/for_sale.html

Jas.
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Old 12-27-2011, 11:59 AM
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Good call, I just ordered one!
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Old 12-27-2011, 12:42 PM
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I tend to use my 1970's SS Heathkit generators.
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Zenith: The quality stays in EVEN after the name falls off!
What I want. --> http://www.videokarma.org/showpost.p...62&postcount=4
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Old 12-27-2011, 04:20 PM
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I always liked this one which I refer to as "Old boring B&W movie about Indians".

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Old 12-28-2011, 07:09 AM
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I always liked this one which I refer to as "Old boring B&W movie about Indians".

This brings up an interesting point. What was the meaning of the numbers in the diagram? While they may be measurements of some kind, one can only imagine that it's actually a points score for a TV based bean bag toss
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Old 12-28-2011, 12:47 PM
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This brings up an interesting point. What was the meaning of the numbers in the diagram? While they may be measurements of some kind, one can only imagine that it's actually a points score for a TV based bean bag toss
Aah, TV Indian bean bag toss a favorite among late night drinking buddies and early risers that owned protelgram projectors.
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Old 12-28-2011, 12:56 PM
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Quote:
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This brings up an interesting point. What was the meaning of the numbers in the diagram? While they may be measurements of some kind, one can only imagine that it's actually a points score for a TV based bean bag toss
I believe that they define the resolution scale in various parts of the "wedges" from 200 to 450 lines in the center and 200 to 350 at the corners

jr
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Old 12-28-2011, 02:28 PM
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Quote:
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I believe that they define the resolution scale in various parts of the "wedges" from 200 to 450 lines in the center and 200 to 350 at the corners

jr
Yes, resolution in "TV Lines per picture height." 330 lines is the most you could get on a broadcast signal with a black and white set (or color set with comb filter). Maybe 270 lines horizontal with a color set with 3.58 MHz trap.
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Old 12-28-2011, 05:37 PM
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Quote:
Originally Posted by jr_tech View Post
I believe that they define the resolution scale in various parts of the "wedges" from 200 to 450 lines in the center and 200 to 350 at the corners
NBC, oddly enough, had a layout of their famed "bullseye" pattern in which they explained what the significance of the wedge calibration dots as positioned on each side of their horizontal and vertical wedges, were:



Alas, I haven't heard, seen or read anything about this variation being seen on the air.

NOTE: 200 TV lines = 2.5 MHz (or "mc," as it was known as of 1947).

Last edited by W.B.; 11-03-2023 at 05:45 PM.
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Old 08-25-2012, 02:22 AM
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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, 66 views)
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Old 10-09-2012, 10:34 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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  #15  
Old 12-20-2015, 09:20 PM
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As I'd noted in earlier posts, the color circular test pattern design (first unveiled in 1965) 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; five stations were confirmed to use it - KYW Channel 3 and WIBF (later WTAF and now WTXF) Channel 29 in Philadelphia, PA; WCMC (now WMGM) Channel 40 in Wildwood, NJ; 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 . . . ?

Last edited by W.B.; 06-05-2021 at 09:42 AM. Reason: KYW use of East Coast TP added, and year first introduced.
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