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  #76  
Old 04-19-2015, 09:47 AM
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Quote:
Originally Posted by Electronic M View Post
That blush of color in the lower multi-burst pattern shows the color circuits reacting to what should be a monochrome signal. It would be interesting to know the frequency at which this is occurring. It could be alignment issues or it could be a design limitation of the set lacking a comb/notch filter.
I'd like to help you with that, but it could be a while until I get my hand on the required equipment to do so.
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  #77  
Old 04-19-2015, 12:18 PM
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I tried, various setup of brightness/contrast , and it is true that higher contrast (lower brightness) seems to help a bit, but the worst offender here is the "color" ajusting. I can get the color where it's not blooming that much anymore...but the picture gets very dull (not much colors).

Could it be that, a mix of cheap RF modulation and macrovision fed to a television that wasn't desing to receive and process that kind of signal could "degrade" the picture like that? How do you guys with roundy go about to get the very best image on your sets?

Oh and BTW, I am still not getting any snow when the TV receive no signal, only a white uniform picture. Could it give a clue to what's wrong?

Thanks!
Lack of snow with no signal is completely separate from your color issues - I'm only going to talk about color setup:

You say that lower brightness "seems to help" but from your pictures the "brightness" (or "black level," not "contrast" or "picture") is too low already. You should see uniform steps in the gray scale with only the darkest one being black. Secondly, your complaints about color being washed out tell me that you are looking subjectively for uncalibrated overly saturated color. To get (approximately) calibrated color, you first need to get the gray scale correct, then view the color bars through a blue filter and adjust hue (tint) and saturation (color) to get all the blue-containing colors to have the same amount of blue (looking the same through the blue filter) as shown on this page:
http://www.spearsandmunsil.com/portf...r/#prettyPhoto

My guess from your comments is that you will not like this accurate setup, but at least it gives you a known starting point for adjusting towards your preference.
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  #78  
Old 04-19-2015, 12:37 PM
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A few things.
Looking at you pix if its accurate its a little purple.
Try adding just a little green.
The pattern looks pretty good. The bottom bar is for
resolution & looks normal. If the set had a comb filter
the blue wouldnt be as bad & you would see more
lines to the right of it ( the high freqs for detail ).
The CRT looks just a tad weak. You cant always go
by the checker for that. I never harmed anything
with the clean & balance so maybe try that.
The Hitachi probably has a comb filter, most mid to high
end sets had them by the mid 80's. Thats much of the
reason for better small white lettering.

BTW Did we cover the HV control on this yet ??

73 Zeno
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  #79  
Old 04-19-2015, 02:23 PM
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Quote:
Originally Posted by Dreamsbeard View Post
I'd like to help you with that, but it could be a while until I get my hand on the required equipment to do so.
You don't need equipment (although some equipment can do that)...Just a DVD with a multiburst pattern that bothers to label the frequency of the burst bars on the pattern. If that pattern just had some labels it would tell me a lot about what is happening.
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  #80  
Old 04-19-2015, 06:40 PM
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Quote:
Originally Posted by Electronic M View Post
You don't need equipment (although some equipment can do that)...Just a DVD with a multiburst pattern that bothers to label the frequency of the burst bars on the pattern. If that pattern just had some labels it would tell me a lot about what is happening.
No need for labels or further tests - it is at the color subcarrier frequency, just as it should be. You can also see the notch in the luma response in the monochrome picture.
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  #81  
Old 04-23-2015, 04:57 PM
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Quote:
Originally Posted by old_tv_nut View Post
Lack of snow with no signal is completely separate from your color issues - I'm only going to talk about color setup:

You say that lower brightness "seems to help" but from your pictures the "brightness" (or "black level," not "contrast" or "picture") is too low already. You should see uniform steps in the gray scale with only the darkest one being black. Secondly, your complaints about color being washed out tell me that you are looking subjectively for uncalibrated overly saturated color. To get (approximately) calibrated color, you first need to get the gray scale correct, then view the color bars through a blue filter and adjust hue (tint) and saturation (color) to get all the blue-containing colors to have the same amount of blue (looking the same through the blue filter) as shown on this page:
http://www.spearsandmunsil.com/portf...r/#prettyPhoto

My guess from your comments is that you will not like this accurate setup, but at least it gives you a known starting point for adjusting towards your preference.
You are right, I do adjust everything by eye, but do not worry I know oversaturation when I see it. I adjust everything to get the most natural looking picture (NOT what you can see in department store where every TV are on torch mode with cartoonish colors). That being said, the reference picture you saw where at the low brightness and contrast setting for convergence adjustement, and are not the setting I use to "test" the TV normaly.

Last edited by Dreamsbeard; 04-23-2015 at 05:02 PM.
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  #82  
Old 04-23-2015, 05:01 PM
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Quote:
Originally Posted by zeno View Post
A few things.
Looking at you pix if its accurate its a little purple.
Try adding just a little green.
The pattern looks pretty good. The bottom bar is for
resolution & looks normal. If the set had a comb filter
the blue wouldnt be as bad & you would see more
lines to the right of it ( the high freqs for detail ).
The CRT looks just a tad weak. You cant always go
by the checker for that. I never harmed anything
with the clean & balance so maybe try that.
The Hitachi probably has a comb filter, most mid to high
end sets had them by the mid 80's. Thats much of the
reason for better small white lettering.

BTW Did we cover the HV control on this yet ??

73 Zeno
We did, but I don't have a high voltage probe as of now. What could be the symptomes of a badly adjusted HV?
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  #83  
Old 04-23-2015, 05:45 PM
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Quote:
Originally Posted by Dreamsbeard View Post
You are right, I do adjust everything by eye, but do not worry I know oversaturation when I see it. I adjust everything to get the most natural looking picture (NOT what you can see in department store where every TV are on torch mode with cartoonish colors). That being said, the reference picture you saw where at the low brightness and contrast setting for convergence adjustement, and are not the setting I use to "test" the TV normaly.
Aha - thanks for clarifying.
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  #84  
Old 04-23-2015, 07:02 PM
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If the set has a HV adjust control they got bad spots.
IIRC it was on the right side of chassis & covered with
a metal cover.
If bad the width on right side would come in about 1/2 inch & there
is usually a bar in the pix at the side. Moving the control
a tiny bit makes it pop in.

73 Zeno
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