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  #1  
Old 12-27-2011, 10:56 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, 11:05 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, 11:08 AM
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I have a color bar generator for sale.
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Old 12-27-2011, 12:29 PM
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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, 12:59 PM
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Good call, I just ordered one!
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Old 12-27-2011, 01:42 PM
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I tend to use my 1970's SS Heathkit generators.
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Old 12-27-2011, 05:20 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, 12:16 AM
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The old round test patterns (Indian head and ones used by local stations) aren't needed much anymore with sets from about the 1980s to now (especially the latter), which is probably why TV stations, the few that that still sign off at one or 2 a.m., anyway, use the color bar test chart, with their call signs, channel numbers and city of license in the black area below the bars, but ahead of the large white square at the extreme right edge of the chart. The round pattern is useful when adjusting image proportions (height, linearity, width) on old sets that have variable controls for such, while the color charts can be put to good use when adjusting the 3.58-MHz color burst phase (or to diagnose color registration problems) on vintage color sets.

Some local TV stations put their call signs and channel number on the Indian head pattern as well. Many years before American and Canadian television went digital (also before I had cable), I remember seeing a pattern from CFPL-TV in London, Ontario with just that information at the top of the pattern. I could also get Windsor's CKLW-TV (now CBET) channel 9 when the conditions were right, but I don't remember ever seeing their location and channel info on their test pattern.

At least one Cleveland TV station (NBC affiliate WKYC on channel 3) used a round test pattern with color segments built right into the pattern. Never saw anything like it; in fact, I think that station was the only Cleveland TV station to use such a unique test pattern. Channel 5 had a standard round pattern, as did channel 8, although 8's pattern also, IIRC, had color segments incorporated into it. Cleveland's PBS channel 25, which first signed on in 1965, had a round b&w pattern, no color bars or segments; however, when Cleveland's first commercial UHF station went on the air in 1968, it used a squarish test pattern with one small color bar chart at the top, IIRC. The station's call letters were placed below that chart, with one letter of the call sign appearing directly over the vertical resolution test wedge.

Channel 19's test signal was simply a color chart, with the station's call sign and location info at the base of the chart -- again, very near the white square at the right edge. An independent station on channel 55 (now an affiliate of The CW) that went on the air in 1985 in the Cleveland area, but was licensed to and was intended to serve an area 30 miles southwest of the city, also used a color chart; somewhere, I have a VHS video tape on which I recorded the station's test signal after the end of a program. The station is WBNX-TV, CW55, Akron-Cleveland, Ohio. To the best of my knowledge and belief, however, they never used a round test pattern; neither, for that matter, did Cleveland's original channel 61, Kaiser Broadcasting WKBF-TV (now WQHS-TV Univision 61). Maybe by this time (late '60s), traditional test patterns had gone out of style?
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Last edited by Jeffhs; 12-28-2011 at 12:21 AM.
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  #9  
Old 12-28-2011, 12:39 AM
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The Leader LCG400 ntsc generator dominates. Nothing comes close. The DVD would be a second choice.
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  #10  
Old 12-28-2011, 12:54 AM
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Here is a post that I made several years ago showing the 2F21 "Monoscope" CRT used to generate the "Indian Head" pattern. RCA would indeed provide custom versions of the pattern with call letters and perhaps other info printed on the target.

http://www.videokarma.org/showpost.p...5&postcount=29

jr
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  #11  
Old 12-28-2011, 01:58 AM
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I use a Leader pattern generator most of the time. It has a small workbench footprint and works great. At other times, for various reasons, I may use the Sencore VA62 video analyzer, or a test pattern DVD, or (when feeling nostalgic and not very scientific) the BK 1077B TV analyst.

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  #12  
Old 12-28-2011, 04:42 AM
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The old round test patterns (Indian head and ones used by local stations) aren't needed much anymore with sets from about the 1980s to now (especially the latter), which is probably why TV stations, the few that that still sign off at one or 2 a.m., anyway, use the color bar test chart, with their call signs, channel numbers and city of license in the black area below the bars, but ahead of the large white square at the extreme right edge of the chart. The round pattern is useful when adjusting image proportions (height, linearity, width) on old sets that have variable controls for such, while the color charts can be put to good use when adjusting the 3.58-MHz color burst phase (or to diagnose color registration problems) on vintage color sets.

Some local TV stations put their call signs and channel number on the Indian head pattern as well. Many years before American and Canadian television went digital (also before I had cable), I remember seeing a pattern from CFPL-TV in London, Ontario with just that information at the top of the pattern. I could also get Windsor's CKLW-TV (now CBET) channel 9 when the conditions were right, but I don't remember ever seeing their location and channel info on their test pattern.

At least one Cleveland TV station (NBC affiliate WKYC on channel 3) used a round test pattern with color segments built right into the pattern. Never saw anything like it; in fact, I think that station was the only Cleveland TV station to use such a unique test pattern. Channel 5 had a standard round pattern, as did channel 8, although 8's pattern also, IIRC, had color segments incorporated into it. Cleveland's PBS channel 25, which first signed on in 1965, had a round b&w pattern, no color bars or segments; however, when Cleveland's first commercial UHF station went on the air in 1968, it used a squarish test pattern with one small color bar chart at the top, IIRC. The station's call letters were placed below that chart, with one letter of the call sign appearing directly over the vertical resolution test wedge.

Channel 19's test signal was simply a color chart, with the station's call sign and location info at the base of the chart -- again, very near the white square at the right edge. An independent station on channel 55 (now an affiliate of The CW) that went on the air in 1985 in the Cleveland area, but was licensed to and was intended to serve an area 30 miles southwest of the city, also used a color chart; somewhere, I have a VHS video tape on which I recorded the station's test signal after the end of a program. The station is WBNX-TV, CW55, Akron-Cleveland, Ohio. To the best of my knowledge and belief, however, they never used a round test pattern; neither, for that matter, did Cleveland's original channel 61, Kaiser Broadcasting WKBF-TV (now WQHS-TV Univision 61). Maybe by this time (late '60s), traditional test patterns had gone out of style?
The circular color test pattern used by WKYC beginning around 1968 or at the latest 1970 (prior to then, they used the customary B&W NBC bullseye) was used by many different TV stations across the country, but mostly in the eastern half of the continental U.S.; very few in the western half used it. Other stations using this pattern (with a few alterations over the years) included:
- WIBF (Channel 29, later WTAF and now WTXF), Philadelphia, PA
- WNDT (Channel 13, now WNET), Newark, NJ/New York City*
- WNJU (Channel 47), Linden/Newark, NJ*
- WFLD (Channel 32), Chicago
- WLS (Channel 7), Chicago (the famed "Sears Tower/Circular Polarization" layout)
- WHBF (Channel 4), Rock Island, IL
- WNJT (Channel 52), Trenton, NJ
- WTVS (Channel 56), Detroit
- WMUR (Channel 9), Manchester, NH
- WAPA (Channel 4), San Juan, PR*
- WOR-TV (Channel 9), New York*
- WETA (Channel 26), Washington, DC
- WYTV (Channel 33), Youngstown, OH
- WOUB (Channel 20), Athens, OH / WOUC (Channel 44), Cambridge, OH (both stations on one pattern)
- WLVI (Channel 56), Cambridge/Boston
- WTTG (Channel 5), Washington, DC*
- WKBS (Channel 48), Burlington/Philadelphia*
- WSMW (Channel 27, now WUNI), Worcester, MA
- KGO (Channel 7), San Francisco*
* custom layout with station logos included
and a few had that pattern in varying black-and-white form, such as:
- KAET (Channel 8), Phoenix
- WQED (Channel 13), Pittsburgh*
- WMAH (Channel 19), Biloxi, MS and WMAW (Channel 14), Meridian, MS
- YSR-TV (Canal 2), El Salvador
(I was also informed that WRGB Channel 6 in Schenectady, NY, also used it, but have not seen any examples.)
By the late 1970's, that particular color TP design was turned upside-down; as such it was used by WRC-TV (Channel 4), Washington, DC, and the stations of South Dakota Public Television (including KUSD Channel 2 in Vermillion). I.I.N.M., it was also used in that upside-down form by KHET (Channel 11), Honolulu / KMEB (Channel 10), Wailuku, in Hawaii.

Here are two particular variations:



(Would anyone know which other stations across the country would've used this overall pattern, in either form?)

After c.1979-80, there was a redesign of the pattern with a completely different set of colors:



which, in this form, was used by the following stations (again, a partial list):
- WABC (Channel 7), New York*
- WPIX (Channel 11), New York
- WKBW (Channel 7), Buffalo, NY
- WTVE (Channel 51), Reading, PA
- WTTG*
- WOUB/WOUC
- WCGV (Channel 24), Milwaukee
- WSBK (Channel 38), Boston
- WOLF (Channel 38), Scranton, PA
- WNEV (Channel 7 - formerly WNAC, now WHDH), Boston
- WTTE (Channel 28), Columbus, OH
- WICZ (Channel 40), Binghamton, NY
- WVAH (Channel 23 - now on Channel 11), Charleston/Huntington, WV
As with the earlier pattern, two Mississippi public TV stations - WMAH, plus WMAV (Channel 18) in Oxford-University - aired this pattern in a form of black-and-white which apparently entailed running only the red channel across the other two (green and blue) channels. And again, can anyone advise which other stations would have used this?

The selfsame NBC bullseye test pattern that was used as the basis for this color pattern, was also adapted by their New York outlet WNBC (Channel 4) for a completely different color test pattern that was used beginning in 1975 and well into the late 1980's/early '90's:



WVIZ had used a color adaptation of the 1956 RETMA/EIA resolution chart; which was also in use for some two decades at WUAB (Channel 43).

And the Indian head was not the only pattern from RCA for use on monoscopes; they also had a lined bullseye test pattern which was also in use by a number of stations in the U.S. and Canada (another station in the latter country being Hamilton's CHCH Channel 11), as seen below:



(Some stations used both Indian and RCA bullseye, namely KRLD Channel 4, now KDFW, in Dallas.)

This pattern (albeit without the particular wedges on the top right and bottom left sides) was also altered with a few other elements by the stations of Crosley/Avco Broadcasting beginning in the late 1950's and in use at their TV stations (verified as at WLWT Channel 5, Cincinnati; WLWD Channel 2, now WDTN, Dayton; and WLWI Channel 13, now WTHR, Indianapolis).

And who could forget the test pattern of CBS-owned and -affiliated stations, whose layout has been compared by DX'ers to an archery target:


Last edited by W.B.; 11-06-2015 at 02:20 PM. Reason: Addition of new stations (WIBF, WETA, WOLF) and moving WQED to B&W list
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  #13  
Old 12-28-2011, 08:06 AM
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I remember the color test pattern on WKBW. Oddly enough, it came on about a half hour before the station signed on the air in the morning. Before that, it was the typical color bars. I always thought, man, those TV repairmen that have to get their sets aligned sure do have to get up early in the morning!
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  #14  
Old 12-28-2011, 08:09 AM
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Quote:
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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, 01:47 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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