24" Widescreen CRT (FW900) From Ebay arrived,Comments.

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This monitor seems to do really well with 5:4 but I have updated to 1366x1024@110Hz and all is good. I am not sure on the YCbCr, is there something I can test? I am running a 1080Ti
I'm sure it does "well" with 5:4, it's just stretched horizontally on CRT's because they're 4:3.

But YCbCr will be in the resolution tab, under "color format"
 

Yuriy83

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The top Eizo & Iiyama CRTs seemed better than any Trinitrons I've seen. Anyone own both an FW900 & either and Eizo or Iiyama? The Iiyama visionm pro 514 is the best I've seen.
I haven't seen Eizo & Iiyama, but FW900 doesn't have the best quality amongst trinitrons to be honest. I like F520 better. FW900 has this weird phosphor / coating compared to other models. F520 and even G500 have better percieved contrast and color saturation in my opinion, while handling reflections better.
 

SH1

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I haven't seen Eizo & Iiyama, but FW900 doesn't have the best quality amongst trinitrons to be honest. I like F520 better. FW900 has this weird phosphor / coating compared to other models. F520 and even G500 have better percieved contrast and color saturation in my opinion, while handling reflections better.
F520 has a proper coating. FW900 has that glued on plastic film. Maybe Sony would have addressed this in a successor, but then it all ended.
 

P1x3L

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I wonder if there are enough enthusiasts online to justify producing the next top-end CRT...
 

Strat_84

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Don't dream too much of that. The expertise on high performance CRTs tubes has probably been lost by now. All factories have been dismantled, and as far as I know the only few CRT tubes that may still be manufactured are low end oscilloscope displays. On the top of that CRT displays require some components with very specific characteristics (horizontal deflection transistor for instance) that have been discontinued as well. It's not just dependant of a single company, the entire production chain is gone.
 

P1x3L

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Don't dream too much of that. The expertise on high performance CRTs tubes has probably been lost by now. All factories have been dismantled, and as far as I know the only few CRT tubes that may still be manufactured are low end oscilloscope displays. On the top of that CRT displays require some components with very specific characteristics (horizontal deflection transistor for instance) that have been discontinued as well. It's not just dependant of a single company, the entire production chain is gone.
There's no way a bunch of the engineers who built Eizo, NEC, Iiyama, and Sony CRTs aren't still alive...
 

Yuriy83

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There's no way a bunch of the engineers who built Eizo, NEC, Iiyama, and Sony CRTs aren't still alive...
That's not the problem. They would have to rebuild many production lines to produce various components. It wasn't profitable for them to maintain in the 2000s, it would be even less profitable to build everything from scratch today. A CRT display today would have to cost a fortune to justify the expenses. Not happening.
 

XoR_

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The top Eizo & Iiyama CRTs seemed better than any Trinitrons I've seen. Anyone own both an FW900 & either and Eizo or Iiyama? The Iiyama visionm pro 514 is the best I've seen.
Color quality of FW900 is pretty mediocre as is contrast. It is due to phosphors they used in this model. Some other Trinitrons I used like IBM P275 and Dell P1110 used much better phosphors/filters and color quality was much better.
Diamondtrons used even better phosphors and also different gun layout giving to better colors/contrast and sharpness respectively.

Actually it is only the larger and widescreen aspect ratio that makes FW900 so desirable. Other than that there are better and much cheaper alternatives available.
 

XoR_

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F520 has a proper coating. FW900 has that glued on plastic film. Maybe Sony would have addressed this in a successor, but then it all ended.
When I had IBM P275 friend of mine bought some older non-flat Trinitron and it used exactly the same phosphor and coating as GDM-FW900 and thus also had inferior color/contrast.
If CRT era was allowed to continue some more then we would definitely have much better displays to choose from today, including Diamondtron offerings. This is so sad :(
 

XoR_

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I wonder if there are enough enthusiasts online to justify producing the next top-end CRT...
Not happening
Besides, right now we are at the brink of OLED explosion and you also need to have wide-gamut and high dynamic range capabilities while CRT are quite dim to begin with and putting even more saturated phosphors would make these displays even dimmer.
Oh, and did I mention "green" or "eko" regulations? CRT consume tons of power and use (considered to be) hazardous materials in their production... on top of that there is fabrication facilities being lost issue.

Some small production could be done if some millionaire insisted on making this happen but those people usually do not do stuff that would only make them loose their money, they also need to have some profits or at the very least get even. So not going to happen.
 
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Finally managed to get my hands on a FW900 :)
The AG film was destroyed so I had to remove it entirely. I must say the colors on this thing are beautiful. Geometry is perfect. Had some convergence issues but fixed them entirely with the Dcnv procedure in WINDAS and now it's perfect! Gotta love the fact it has 135 zones to adjust compared to 45 as my two F520 and one Dell P1130 have AND the 4 controls instead of 2 (adjust the green beam separetely). It took me 4 days to complete it with warmups up to 10 hours before calibration to make sure it doesn't drift any further and now it's perfect even in the corners or sides of the image!
Unfortunately the monitor has severe focus problems :(
I spent hours and hours trying to fix this but with no luck. Check out the photos. The focus is good and sharp in the center but as you move to the top or the bottom of the image the horizontal lines become more blurry and foggy. Adjusting the two focus pots on the FBT can solve the problem at the top and bottom of the image but at the expense of the center of the screen which is unacceptable.
Curiously, the focus is very good on the sides of the monitor with no thickening of the lines as you go up or down, considering they are furthest apart from the center of the screen. The issue is present only on the top-middle and bottom-middle parts of the screen. So if you were to look at the first horizontal line at the top of the screen, it is very focused on the hard left and hard right of the screen but becomes extremely blurry as you move toward its middle section.
I even played with some dynamic focus parameters found in WINDAS. For the CR1 chassis (F520, Dell P1130, etc) you have HDF_DELAY_LO and HDF_DELAY_HI. On the FW900 you have two awkward ones: H_SIZE_ORIGIN and H_DF_XB3_HI but they only affect the sides of the screen not the top-middle and bottom-middle parts :(
Any suggestions?
 

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P1x3L

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That's not the problem. They would have to rebuild many production lines to produce various components. It wasn't profitable for them to maintain in the 2000s, it would be even less profitable to build everything from scratch today. A CRT display today would have to cost a fortune to justify the expenses. Not happening.
What evidence is there that companies didn't kill the CRT due to it not having the profit margin that the LCD has... Versus Not making enough profit to keep a company running? The LCD killed the CRT, the CRT did not kill himself ;)
 

Strat_84

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Finally managed to get my hands on a FW900 :)
The AG film was destroyed so I had to remove it entirely. I must say the colors on this thing are beautiful. Geometry is perfect. Had some convergence issues but fixed them entirely with the Dcnv procedure in WINDAS and now it's perfect! Gotta love the fact it has 135 zones to adjust compared to 45 as my two F520 and one Dell P1130 have AND the 4 controls instead of 2 (adjust the green beam separetely). It took me 4 days to complete it with warmups up to 10 hours before calibration to make sure it doesn't drift any further and now it's perfect even in the corners or sides of the image!
Unfortunately the monitor has severe focus problems :(
I spent hours and hours trying to fix this but with no luck. Check out the photos. The focus is good and sharp in the center but as you move to the top or the bottom of the image the horizontal lines become more blurry and foggy. Adjusting the two focus pots on the FBT can solve the problem at the top and bottom of the image but at the expense of the center of the screen which is unacceptable.
Curiously, the focus is very good on the sides of the monitor with no thickening of the lines as you go up or down, considering they are furthest apart from the center of the screen. The issue is present only on the top-middle and bottom-middle parts of the screen. So if you were to look at the first horizontal line at the top of the screen, it is very focused on the hard left and hard right of the screen but becomes extremely blurry as you move toward its middle section.
I even played with some dynamic focus parameters found in WINDAS. For the CR1 chassis (F520, Dell P1130, etc) you have HDF_DELAY_LO and HDF_DELAY_HI. On the FW900 you have two awkward ones: H_SIZE_ORIGIN and H_DF_XB3_HI but they only affect the sides of the screen not the top-middle and bottom-middle parts :(
Any suggestions?
You should never have to touch the potentiometers on the flyback, they are always adjusted perfectly from the start and you can only make this worse. In your case there may be a failure somewhere on the D board impacting the horizontal/vertical dynamic focus circuits. The horizontal lines sharp in the center and blurry on the bottom/top are typical of a dynamic focus issue.
 
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You should never have to touch the potentiometers on the flyback, they are always adjusted perfectly from the start and you can only make this worse. In your case there may be a failure somewhere on the D board impacting the horizontal/vertical dynamic focus circuits. The horizontal lines sharp in the center and blurry on the bottom/top are typical of a dynamic focus issue.
Focus does drift due to moisture and temperature variations. I've seen it on one too many CRTs. More to that, not all of them are perfectly calibrated at the factory. Anyway, that is not an issue, I'm quite skilled at refocusing them, I've done it hundreds of times and I use a magnifing lens ;)
Now, you say is a D-board issue? The thing is the two windas parameters I mentioned earlier do work in making a difference but not the one I need AND I've seen this exact issue on a Samsung 19" 997MB monitor that was pretty used up. Changing the ENTIRE mainboard from a new one did nothing to correct this. Ofcourse I tried refocusing but with no succes. This FW900 is also beat-up and I got it for free so I'm trying to exhaust all possibilities before getting rid of it.
 

Strat_84

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Focus does drift due to moisture and temperature variations. I've seen it on one too many CRTs. More to that, not all of them are perfectly calibrated at the factory. Anyway, that is not an issue, I'm quite skilled at refocusing them, I've done it hundreds of times and I use a magnifing lens ;)
Now, you say is a D-board issue? The thing is the two windas parameters I mentioned earlier do work in making a difference but not the one I need AND I've seen this exact issue on a Samsung 19" 997MB monitor that was pretty used up. Changing the ENTIRE mainboard from a new one did nothing to correct this. Ofcourse I tried refocusing but with no succes. This FW900 is also beat-up and I got it for free so I'm trying to exhaust all possibilities before getting rid of it.
Well, the problem looks very much like something wrong with the dynamic focus. It's hard to be more specific without checking the monitor. ;)
But the failures possibilities I can think of are the following:
- the most obvious, something failed directly in the dynamic focus circuits (D board then). In such case it would be more likely to have a problem on vertical or horizontal focus though, not both.
- something wrong with one or several lines of the power supply (G board) which then affects the circuits controlling focus.
- something wrong with the control circuitry generating the signals for dynamic focus (N board)
- a failure of some components in the vicinity of the flyback or the flyback itself (D board again).

I can't say anything about the Samsung as I don't know that model and I can't find a service manual. I don't know either what kind of circuitry is on the mainboard.
 
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Well, the problem looks very much like something wrong with the dynamic focus. It's hard to be more specific without checking the monitor. ;)
But the failures possibilities I can think of are the following:
- the most obvious, something failed directly in the dynamic focus circuits (D board then). In such case it would be more likely to have a problem on vertical or horizontal focus though, not both.
- something wrong with one or several lines of the power supply (G board) which then affects the circuits controlling focus.
- something wrong with the control circuitry generating the signals for dynamic focus (N board)
- a failure of some components in the vicinity of the flyback or the flyback itself (D board again).

I can't say anything about the Samsung as I don't know that model and I can't find a service manual. I don't know either what kind of circuitry is on the mainboard.
I was trying to point out that the tube itself might be worn out. I'm the third user and the second user got it refurbished as far as I know. Due to aging, the cathodes's surface that emits electrons increases because the central part loses emission material thus the focal point becomes a larger spot. The monitor can't maintain an uniform focus across the screen. In a way the monitor loses "resolution".
Now, if you look at the pictures, the problem affects ONLY the horizontal lines NOT the vertical ones.
The FBT looks ok in my opinion. Both pots glide smoothly without any jumps and I can set the focus perfectly top and bottom but doing so sacrifices the center.
 

Strat_84

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I was trying to point out that the tube itself might be worn out. I'm the third user and the second user got it refurbished as far as I know. Due to aging, the cathodes's surface that emits electrons increases because the central part loses emission material thus the focal point becomes a larger spot. The monitor can't maintain an uniform focus across the screen. In a way the monitor loses "resolution".
Now, if you look at the pictures, the problem affects ONLY the horizontal lines NOT the vertical ones.
The FBT looks ok in my opinion. Both pots glide smoothly without any jumps and I can set the focus perfectly top and bottom but doing so sacrifices the center.
Except if it were a tube issue you'd have the same focus issue on the entire display area. So no.

If I look at the pictures it seems both lines are affected, but these aren't very good pictures. You have the screen in front of you, if you tell me the problem is only with the horizontal lines then you have your answer. The problem is either with the vertical dynamic focus section of the circuit on the D board, the +15V / -15V lines or the N board.

edit: ahaha, mistake. :p
Looking back at the schematics the vertical dynamic focus is a circuit actually separated from the vertical deflection. That kind of signal goes to the flyback.
 
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SH1

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When I had IBM P275 friend of mine bought some older non-flat Trinitron and it used exactly the same phosphor and coating as GDM-FW900 and thus also had inferior color/contrast.
If CRT era was allowed to continue some more then we would definitely have much better displays to choose from today, including Diamondtron offerings. This is so sad :(
I've found the picture quality of the FW900 to be great. Not quite that of the F520, where the thing I most noticed is the latter display's superior uniformity in luminance across the screen.

Blacks definitely suffered with the antireflective film removed. Still liking the Kantek filter.

Very sad indeed that CRT production ended without a proper successor in terms of raw PQ. OLED first sign of such a successor hopefully.
 
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Except if it were a tube issue you'd have the same focus issue on the entire display area. So no.

If I look at the pictures it seems both lines are affected, but these aren't very good pictures. You have the screen in front of you, if you tell me the problem is only with the horizontal lines then you have your answer. The problem is either with the vertical dynamic focus section of the circuit on the D board, the +15V / -15V lines or the N board.

edit: ahaha, mistake. :p
Looking back at the schematics the vertical dynamic focus is a circuit actually separated from the vertical deflection. That kind of signal goes to the flyback.
Thank you Strat, I'll investigate. It looks like I have a new project/hobby on my hands :)
I hope I can find quality spare parts such as capacitors or transistors if I decide to delve deeper into this. :)
 

Strat_84

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You'll have absolutely no problem finding a replacement for basic components like resistors, capacitors, diodes. It becomes really tricky only with integrated circuits (often discontinued and specific) and some old transistors/mosfets that have no recent equivalent.
 

kohan69

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Thanks, I'm glad to share this. :)

My screen didn't have much of an issue except old age, and its previous owner being a retard calling himself "electronician" and messing with the inside. He desoldered perfectly working memory chips for weird reasons (maybe to try saving the data ?), and broke a few lines in the flat cables linking the boards in the dismantling process. That led to the display contracting itself vertically. The G2 voltage was also completely messed up but this is pretty common.
It took a long time before I found the cable issue and I had already made a full recap for electrolytics, and many film and ceramic capacitors. Some replacements weren't really necessary, but I intended to restore that screen as completely as possible anyway, and to investigate the boards to find if some limited improvements were possible while I was on it.

One obvious detail I forgot to mention about the replacement of C919, you'd be replacing a leaky crappy worn out capacitor with a quality new one, that means a white point balance procedure with Windas is mandatory after the replacement.

Also, you should check the boards for bad solders, there are often some. In your case, according to your description I'd rather think about some capacitor issue on a voltage line. Maybe noise related to horizontal deflection or vertical deflection, or both, is making its way back on these lines and reaching areas it shouldn't. But it's only a guess, you'd need an oscilloscope to check this. ;)
I have access to an oscilloscope. Would be neat to diagnose it properly!
 

Strat_84

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You should rather send him a private message (you need enough posts on the forum for that if I remember well, maybe 10 ?).

But don't be too optimistic, Uncle Vito hasn't shown up for nearly 2 years, it's likely he sold everything he had and went out of business.
 
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You'll have absolutely no problem finding a replacement for basic components like resistors, capacitors, diodes. It becomes really tricky only with integrated circuits (often discontinued and specific) and some old transistors/mosfets that have no recent equivalent.
I opened up the FW900 and checked the voltage lines from the G board (power supply board). I monitored the voltages for an hour:
+15V = 15.13V stable
-15V = -15.10V stable
+5V = 5.00V stable
+12V = 12.01V stable
+220V = varies between 218V and 220V
+80V = 77.5V stable !!!!!

All capacitors in the monitor look ok (no bulging or swelling). I'll dig the +80V line further.
 
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Strat_84

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I opened up the FW900 and checked the voltage lines from the G board (power supply board). I monitored the voltages for an hour:
+15V = 15.13V stable
-15V = -15.10V stable
+5V = 5.00V stable
+12V = 12.01V stable
+220V = varies between 218V and 220V
+80V = 77.5V stable !!!!!

All capacitors in the monitor look ok (no bulging or swelling). I'll dig the +80V line further.
Did you check that with a multimeter or an oscilloscope ?
12V -> keep in mind there is another LDO to provide some 12V from the 15V line on the D board. The 12V you're measuring on the G board is only the "general" 12V line, not the one used on the D board.
The 80V line being a bit low is probably normal (that's actually only about -3%). I don't remember to have seen it reaching 80V, rather 78-79V, and it tends to drop with high contrast/brightness settings.
The +15V/-15V lines may be a bit weird on contrary, I'm surprised to see them that high. I dug in my notes and on GDM-5410s it was in the 14.5-14.8V range. I can't find such measurement for the FW900.

A voltage a bit higher than expected could mean some circuitry supposed to draw power on that line doesn't. And the vertical dynamic focus circuit draws some 15V, that would be consistent with your symptoms, you should definitively check that. A dozen of components are involved, you can find the area in the service manual, D board schematics diagram, bottom left, from the "VDF" signal.
 

christpunchers

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Checked up all the posts from 2019. Seems like there’s much renewed interest in CRTs as of late. Amazing!

I think Vito has retired since 2018. We exchanged a few messages last year. He’s trying to get into some new business. When I’m less busy, I’ll try to entice him on one last attempt to find me the most exquisite FW900 in triple A+ condition to add to my collection of 4 FW900s! He has sources, I’m sure!

Question 1:

So I’m still playing with the Sunix DPU3000 adapter since I got it over a year ago. No major issues. But occasionally it will do its blinking, jittering thing when I use 2304 x 1440 @ 80hz. Doesn’t happen in prime mode (1920 x 1200 @ 84hz — yes 84hz or any even number refresh rate seems to resolve all artifacts). Is there now a better adapter with less problems than the Sunix? Or are we still confirming?

Question 2:

I want to add an AR film to two FW900s without the original AG films. Any recommendations? I talked to Strat84 in the past but he doesn’t think there’s a perfect solution.

I’m not looking for any perfect solution. Just something that can make blacks darker. I’ve found AG-less FW900s to be always more gray even when properly calibrated.

I don’t care about running the tubes a harder or static dust. I’ve read posts on polarizers and car films, etc. Can anyone with experience recommend something I can buy online? Price is not an issue. Just as long as I can cut it size or it comes in custom sizing and gives better blacks without screwing up the image.
 

SH1

[H]ard|Gawd
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Yeah, wow...here's another one:
.

I need to find out more about question 1 myself. For the 2nd question, I'm still very happy with the Kantek solution described earlier. (It's a relatively thick piece of plastic though, needs to be almost touching the screen to minimize distortion, and requires debezelling the way I mounted it.)
 

christpunchers

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Yeah, wow...here's another one:
.

I need to find out more about question 1 myself. For the 2nd question, I'm still very happy with the Kantek solution described earlier. (It's a relatively thick piece of plastic though, needs to be almost touching the screen to minimize distortion, and requires debezelling the way I mounted it.)
When the Kantek filter is kept very close to the glass, is there any distortion at all?
 

SH1

[H]ard|Gawd
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When the Kantek filter is kept very close to the glass, is there any distortion at all?
A slight echo in the lower part of the screen if looking down on something, e.g., text against a black background, through the thickness of the piece of acrylic.

A disadvantage of using an old school filter instead of a film, but overall I'm very pleased.
 

christpunchers

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A slight echo in the lower part of the screen if looking down on something, e.g., text against a black background, through the thickness of the piece of acrylic.

A disadvantage of using an old school filter instead of a film, but overall I'm very pleased.
I see. If you were to try a film with adhesive, which one would it be? Willing to buy one as a test.
 

SH1

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Only other one I purchased was the linear polarizing film discussed earlier, which I think comes in a version with adhesive or maybe you'd need to add your own. Just seemed too dark for me. Liked how the tint of the Kantek is between the original and the polarizing film.
 
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Did you check that with a multimeter or an oscilloscope ?
12V -> keep in mind there is another LDO to provide some 12V from the 15V line on the D board. The 12V you're measuring on the G board is only the "general" 12V line, not the one used on the D board.
The 80V line being a bit low is probably normal (that's actually only about -3%). I don't remember to have seen it reaching 80V, rather 78-79V, and it tends to drop with high contrast/brightness settings.
The +15V/-15V lines may be a bit weird on contrary, I'm surprised to see them that high. I dug in my notes and on GDM-5410s it was in the 14.5-14.8V range. I can't find such measurement for the FW900.

A voltage a bit higher than expected could mean some circuitry supposed to draw power on that line doesn't. And the vertical dynamic focus circuit draws some 15V, that would be consistent with your symptoms, you should definitively check that. A dozen of components are involved, you can find the area in the service manual, D board schematics diagram, bottom left, from the "VDF" signal.
Hi Strat!
I'm at a loss here. I took out and measured the capacitance of every cap on the D board and all of them are within specs (I use quite an expensive professional multimeter).
Out of curiosity, what caps do you usually replace on the D board?
Regarding the +15V/-15V theory I don't agree. I think the G board is working perfectly as the voltages vary between 15.18V on a complete black screen to 15.00V on a complete white screen.
All this leaves me with one culprit, the FBT itself (see pic).
Is it wise to replace it with one from a 4:3 monitor such as the F520? If not, where can I find one, or better yet, the entire D board?
Thanks!
 

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Strat_84

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Hi Strat!
I'm at a loss here. I took out and measured the capacitance of every cap on the D board and all of them are within specs (I use quite an expensive professional multimeter).
Out of curiosity, what caps do you usually replace on the D board?
Regarding the +15V/-15V theory I don't agree. I think the G board is working perfectly as the voltages vary between 15.18V on a complete black screen to 15.00V on a complete white screen.
All this leaves me with one culprit, the FBT itself (see pic).
Is it wise to replace it with one from a 4:3 monitor such as the F520? If not, where can I find one, or better yet, the entire D board?
Thanks!
Your issue isn't necessarily a capacitor issue. And you'd need to desolder them for proper mesurement, I doubt you did that right ? No multimeter can reliably measure both capacitance and ESR in circuit, at least half of the time the capacitor measured is in parallel with several others, or other components between the line and the ground, and the value barely means anything.

I pointed out the area you should check regarding your symptoms, did you do that ? It could be as stupid as a bad solder somewhere there.

About -15/+15V line, you didn't understand what I mean, read again. I didn't say the G board has an issue.

Nope, everytime there's an issue with a CRT it's not the FBT having a problem (I'm tired of reading that again and again, really :censored: ). And no, using a FBT from another model than the correct one is a very bad idea, there's no datasheet for these and no way to know how similar they could be.
 
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Your issue isn't necessarily a capacitor issue. And you'd need to desolder them for proper mesurement, I doubt you did that right ? No multimeter can reliably measure both capacitance and ESR in circuit, at least half of the time the capacitor measured is in parallel with several others, or other components between the line and the ground, and the value barely means anything.

I pointed out the area you should check regarding your symptoms, did you do that ? It could be as stupid as a bad solder somewhere there.

About -15/+15V line, you didn't understand what I mean, read again. I didn't say the G board has an issue.

Nope, everytime there's an issue with a CRT it's not the FBT having a problem (I'm tired of reading that again and again, really :censored: ). And no, using a FBT from another model than the correct one is a very bad idea, there's no datasheet for these and no way to know how similar they could be.
Read my post again.
I desoldered EVERY capacitor, measured it and resoldered again. It took 3 days. Ofcourse I re-did all solder points. That's the first thing I did about a month ago when I got the monitor.
I also measured some resistors (after desoldering them ofcourse) but not all of them. They're ok. The ones that go bad usually change color.
Regarding the +15V and -15V, as I clearly said, the voltage varies with what I'm doing with the monitor. If the screen is black the voltage is high; if the screen is white the voltage drops. This is normal behavior. Everything is ok there.
You haven't answered my questions:
1. What caps do you usually replace on the D board.
2. Do you have an idea where I can find an FW900 FBT or D board?
Thanks!
 

Strat_84

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1°) Well, the point is, given the hassle of desoldering the capacitors, and the relatively low cost, it's not an usual practice to desolder all of them just to check them, especially if there isn't some clue pointing out a capacitor failure. Either this is a "smart" check based on some clue you have, or all are desoldered to be replaced at once.
Unless there is one identified clear failure, it doesn't make sense to replace one (electrolytic) capacitor and not another. Eventually the older one will show aging problems one day when the newer one will still be perfectly fine.

2°) You're asking for a miracle, and I'm no magician. That kind of spare part is long gone, and if you ever have the luck to find some, the price will be prohibitive (plus the risk of defect if it's a used one). But anyway, a FBT failure can be suspected only if the symptoms match and every other possible cause has been ruled out. Your symptoms rather point out different parts, and this doesn't seem to have been extensively checked so ...

In the area I pointed out, there are some resistors to check (no need to desolder unless the reading is really suspicious, what you're looking for are shorts, resistors cut off, or a massive resistance variation that doesn't make sense given the schematics). That alone may point toward some of the other components in the vicinity, then there is a couple of diodes, one ceramic capacitor (make sure it's not shorted to the ground, but if it is, the fusible resistor just before will probably be cut off), a couple of transistors (idealy desolder and check with a component tester, compare values with the datasheet. But some raw checking can be done with a multimeter in diode mode, maybe in circuit).
Now, if that area is good, then check the continuity of the flat cable bringing the VDF signal to the D board, the track may be broken. If the flat cable is OK then things become complicated, you'd need an oscilloscope to make sure there's a "VDF" signal input to the D board. If the "VDF" signal is there, and there's still a matching signal input to the FBT, then it could be a FBT issue. If there's no VDF signal you'd have go down the track to the N board, and then start again the checking work until you find what's wrong.

edit: another possible failure to investigate before having to use an oscilloscope, the 400V line on the D board. If it's down then no signal will reach the FBT.
 
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christpunchers

Limp Gawd
Joined
Dec 26, 2006
Messages
489
For those who watch movies using their CRT: I’m using MadVR with JRiver as the player.

Using 16-235 color setting in MadVR produces great visuals in most HD+ rips that I have. But the annoying thing is that for some rips, the black bars are more gray than black.

If I adjust the blacks to be below 16 or try 0-255 colors, the black bars are black, but the image itself is black crushed.

My FW900 is well calibrated, the blacks are very inky. So it’s not a monitor problem at all.

Is there any tricks in MadVR or otherwise that can get black bars to be black without touching the image itself?
 
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