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

Hey,
after reset in OSD menu, resolutions are working great.
Left : WinDAS Right: my settings in CRU

HIGH setting:

TSBqdFL.png
DVMJIYR.png


MID setting:
KafTo8g.png
c5PB4kP.png


LOW setting:
cYQ6TUw.png
SHfJqRn.png


VESA 1600x1200 setting:
QX65Mgb.png
mlv6PMd.png


I am after geometry adjustments in HIGH mode and I must say that results are very promising, but I need to master my measure workflow. Parallax is killing my eyes.


Also after each turn on / turn off, this unit loses its previous settings, like if I set to 6500K then after restarting it would always go back to 9300K. Brightness and contrast always go back to 50/85. Not really big deal, but little annoying. Seems that someone has clicked MPU in this unit... Hope that going through entire procedure would keep it stable.

thank you spacediver for your kindness! Need to go to sleep for now, tomorrow is gonna be really interesting. I have been thinking about this polarizing foil for almost a year and finally I found glued one that seems to be really high quality and reasonably priced (around $35 per 35cm x 55 cm sheet).
 
I went through and did the calculations for the MID Setting. You're basically correct, but you've made some rounding errors.

Horizontal back porch should be 183 pixels, not 182
And Horizontal front porch should be 23, not 24.

You can also convert more directly by multiplying the H times by the Pixel clock, but the proportional way (which you used) seems to be slightly more accurate (maybe because the listed pixel clock does not show all the significant digits, not sure)

Curious to see how your polarization experiment turns out!
 
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Yeah it was 183 in my calculations as well but I have never encountered odd number in any timings so it made me wonder if I am correct. Would this single pixel make any difference?

Polarization foil has arrived, can't wait till tomorrow.
 
Yeah it was 183 in my calculations as well but I have never encountered odd number in any timings so it made me wonder if I am correct. Would this single pixel make any difference?


I"d be as precise as possbile. I don't know enough about CRTs to answer your question (why odd numbers of pixels aren't often found in the timings, or whether it would make much difference), but what I do know is that when you use the properly calculated values, the other parameters match up more closely.
 
Okay so polarizing foil is ON!

First thoughts:
  • blacks have gotten soooo much better
  • this thing is really really prone to scratching
  • at first encounter I tried to use original glue - result was bad. Really bad TBH. I remember XoR had same problem with huge amount of air bubbles
  • then I took it off and sticked it with water. Had to be very careful not to get any electronics wet, but result is INCREDIBLE. Not a single bubble, it just looks like it was put there in factory
  • it takes off lots of luminance. Without AG it white was 90 cd/m2, now it is 55 cd/m2. WPB to follow.
So to sum up. Im incredibly satisfied but really scratched this sheet of foil, so I'm peeling it off tomorrow and placing new one, this time with protective layer on. After sticking I'm gonna remove protective layer and use as intended. Just quick really cheesy comparison photo:

Sll7haA.jpg


It was just expermiental attachment and other than all these scratches I'm extremely satisfied. So another attempt, calibration and measurements are to follow tomorrow. Hope XoR is about to visit this thread someday as he really misses a lot with all these bubbles.
 
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Wanted to go through WPB just to see it in full glory... but I encountered ABL issue :D(n) damn this thing drove me crazy once and that time I remember that setting G2 tad higher helped, but not tonight. Oh well, gonna fight this tomorrow. Time to party.
 
spacediver did you ever measure the transmittance of the stock ag film?

I remember trying it once with that idea of yours (shining light against a screen with and without AG and measuring luminance of reflection. I'll have to dig up that post and see what results i reported. I remember not getting definitive values.
 
Found it. Here are the posts.

First post
Second post

So, based on my first attempt, looks like around 67% transmittance. When I tried doing the experiment more carefully (in second post), I was unable to get consistent readings.

I never got around to taking those low exposure shots of flashlight reflections though. Still want them?
 
ah totally forgot about that

sure if it's not too much effort


on another topic:
i last did a wpb calibration august 2015. contrast ratio was ~10000:1
during the last few months the black level's drifted such that the contrast ratio is now ~1000:1

is this rate of wear typical?
 
Did you wait several hours before taking the measurement ? Because there's that circuit supposed to compensate a cold tube that increases brightness during maybe the first half an hour; as well as a thermal effect expanding the wires of the mask and making the picture darker after some time running.
 
yea, that's probably coz the guns have to be driven that much harder with your new coating.

I thought about it, but then I realized that I had same problem before. Now I have loaded my first .dat file taken just after I bought my unit with AG on. Luminance is 105 cd/m2, while I couldn't get beyond 65 yesterday. My guess is that sometimes ABL just kicks in for unknown reason. I will try with some other settings.
 
There are 2 ABL related values for the screen, check them. I found that for some obscure reason, if everything isn't matching exactly, these two drop to low levels during the WPB procedure and limit the maximum brightness. Then you have to repeat the WPB again and again to rise these values to normal levels.
 
What do you mean? When I check FAIL_INFO, everything states "NORMAL". Do you suggest to go through WPB few times in a row and that's it?
I mean ABL_SHUTDW_LMT and the next value, must be ABL_CONTRAST_LMT or something like that. These are settings you can see in the same place as the G2, but much lower in the list when you open a .dat file with Help ->Expert.

In a normal state ABL_SHUTDW_LMT should be around 220-230 and the other value a bit below 200. If you find them much lower than that, it's the reason why you have a low brightness.

I had to perform the WPB procedure 7 or 8 times to go back from values around 60-80 to the normal ones. And you can't set them manually as they are set automatically by Windas according to other settings.
 
You were right : at first time I was able to achieve around 65cd/m2, at second 85 cd/m2. I was able to set 6500K and 5000K nominal luminance at second attempt, so I guess at third even 9300K will be fine.
 
ah totally forgot about that

sure if it's not too much effort

K, I won't have time until Monday evening at the earliest, but I will do this.

on another topic:
i last did a wpb calibration august 2015. contrast ratio was ~10000:1
during the last few months the black level's drifted such that the contrast ratio is now ~1000:1

is this rate of wear typical?

yep, black level drifts pretty fast on these tubes, in my experience. I can't remember the last time I did a WPB on mine, but it was at least a year ago. I'll measure my black level (and peak) later today and let you know what mine is
 
You were right : at first time I was able to achieve around 65cd/m2, at second 85 cd/m2. I was able to set 6500K and 5000K nominal luminance at second attempt, so I guess at third even 9300K will be fine.

Check what the ABL values are currently because you may need more passes than that. You might be able to reach the luminance targets, but you may still have the limits triggered. This will make the brightness of the screen vary depending on if it is displaying a full white picture or half black/half white for example.
 
Okay so polarizing foil is ON!

First thoughts:
  • blacks have gotten soooo much better
  • this thing is really really prone to scratching
  • at first encounter I tried to use original glue - result was bad. Really bad TBH. I remember XoR had same problem with huge amount of air bubbles
  • then I took it off and sticked it with water. Had to be very careful not to get any electronics wet, but result is INCREDIBLE. Not a single bubble, it just looks like it was put there in factory
  • it takes off lots of luminance. Without AG it white was 90 cd/m2, now it is 55 cd/m2. WPB to follow.
So to sum up. Im incredibly satisfied but really scratched this sheet of foil, so I'm peeling it off tomorrow and placing new one, this time with protective layer on. After sticking I'm gonna remove protective layer and use as intended. Just quick really cheesy comparison photo:

Sll7haA.jpg


It was just expermiental attachment and other than all these scratches I'm extremely satisfied. So another attempt, calibration and measurements are to follow tomorrow. Hope XoR is about to visit this thread someday as he really misses a lot with all these bubbles.




igsux3, a couple of questions:

1. exactly what type of coating you used and were did you get it? i used a polarized security film which was the closest thing similar to the original one i found where i live.

2. how much reflective your new coaing is comparing to the original older, and also compared with no coating screen,? in your pictures seems some reflectiveness but hard to notice exactly how much.

3. are you having issues with electrostatic with your new coating so dust and other things keep attaching to the coating? if so, how are you dealing with it?

4. i contracted someone experienced with polarized films installations for cars but it was impossible to him to install the film with no bubbles at all, even after 2 attemps, 2 attemp was much better with few small bubbles remaining, maybe due to environment contamination, he used watter and shampo the same way the do for cars window, as illustrated in the photos, he first cleaned the uncoated screen with the tool shown in the picture spraying water on the screen first , then spryed a lot of shampoo to both the uncoated screen and on the side of the film with addesive glue exposed, and mixed with water (forgot to take pictures of that part) and started to attach the film to the screen, then removed the remaining bubbles with some kind of "sponge" as shown in the second picture.
so igsux3, you said you were able to install your coating with no remaining bubbles at all and sticked it with water, can i know how exactly you did? what tools did you use, did you do it on and specific cleaned enviroment?

thanks for sharing ;)

1.jpg
 
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Okay so polarizing foil is ON!

First thoughts:
  • blacks have gotten soooo much better
  • this thing is really really prone to scratching
  • at first encounter I tried to use original glue - result was bad. Really bad TBH. I remember XoR had same problem with huge amount of air bubbles
  • then I took it off and sticked it with water. Had to be very careful not to get any electronics wet, but result is INCREDIBLE. Not a single bubble, it just looks like it was put there in factory
  • it takes off lots of luminance. Without AG it white was 90 cd/m2, now it is 55 cd/m2. WPB to follow.
So to sum up. Im incredibly satisfied but really scratched this sheet of foil, so I'm peeling it off tomorrow and placing new one, this time with protective layer on. After sticking I'm gonna remove protective layer and use as intended. Just quick really cheesy comparison photo:

Sll7haAl.jpg


It was just expermiental attachment and other than all these scratches I'm extremely satisfied. So another attempt, calibration and measurements are to follow tomorrow. Hope XoR is about to visit this thread someday as he really misses a lot with all these bubbles.
AWESOME!
I miss out on FW900 in general because now I am stick to Dell P1110 and FW900 is waiting for better times.
Quality-wise this Dell have imho far better coating from factory than FW900, though not as good as FW900 with polarizer, especially reflection-wise.

What is maximum luminance you can get from your FW900 before sharpness start to decline sharply (at the end of contrast range)?

Generally I will try to stick to CRT's until something like Dell UltraSharp UP3017Q is in my price-range :confused:
 
As far as I understood it was a displayport adapter actually, but yes, still very interested about this too.
 
Edit2: Whew GOT IT ! , was having trouble figuring out how to get the a board off. White plastic cup pulls off the back ! :D

I'm having problems removing it. Anyone know whether it's save to just pull really hard on it?

For reference, here are some images.

8xq5vs.png


A closeup of the white plastic cup:

egd4jo.png
 
hah, sometimes fortune does favour the bold. Carefully ramped up force did the trick.

Now I just gotta figure out the tube number of the FW900 so I can use the Sencore CR70 on it!

14uert1.png
 
Got it.

6iabs2.png


Only problem is, it's not listed in the CR70 manual. Might have to refer to schematics to figure out the proper settings.

upload_2016-12-15_19-23-31.png
 
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Ok here's a puzzle. Looks like this tube is not listed in the manual because the manual's older. So in order to figure out which pin belongs to which parameter, I need to use the schematics in the service manual.

In the Sencore CR70 manual it gives the sort of schematic you should be looking for. There are 7 pins for the relevant values. F1 and F2 refer to filament voltages.

upload_2016-12-15_19-49-40.png


Now in the FW900 service manual, we have this. I think the pin numbers are 1-9 going clockwise, so G2 would be pin 2. The problem is, there are three G1's. I'm assuming H1 and H2 refer to F1 and F2 (filament and heater are interchangeable I think).

upload_2016-12-15_19-53-5.png
 
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This schematic from the service manual makes it clearer. There are 3 G1s, perhaps each corresponding to a different gun. If so, need to figure out which G1 corresponds to which gun.

upload_2016-12-15_20-22-17.png
 
All G1s are connected to the ground so, unless you're connecting to only a single gun at a time, I don't think it really matters to know which G1 pin goes where.
 
I am connecting to a single gun at once. I noticed when I tried pin 3, it didn't work, but pin 6 did. Didn't try pin 11.

I've learned a lot since my last post. Lots more work to do. Will post if I learn anything.
 
Just wanted to chime in and tell you that I appreciate your discoveries, even if it feels like I'm a bit in over my head with CRT servicing at this point, and to keep at it with the learnings.

This information will surely come in handy when it's time to revive my FW900. At the very least, I figure I should test the tube itself on top of replacing whatever blew up inside - if I can even source replacement parts, that is.
 
Just wanted to chime in and tell you that I appreciate your discoveries, even if it feels like I'm a bit in over my head with CRT servicing at this point, and to keep at it with the learnings.

This information will surely come in handy when it's time to revive my FW900. At the very least, I figure I should test the tube itself on top of replacing whatever blew up inside - if I can even source replacement parts, that is.

hopefully I can learn enough to help others here. There are still a couple things I need to figure out :)
 
I think I finally found the last faulty component about my 21" without red and then with an heavy red tint: the RGB amplifier FA4301 (Hitachi). There must be a short or a dead internal diode between the 80V input and the red output.

Problem: it's outdated and no longer produced. I found some references on Chinese websites but it would be very likely to not be the right component or a counterfeit.

The most reliable option to get one seems this distributor in the US: www.sierraic.com . Ever heard of them ? Or any other idea ?
 
I've got a Nokia Multigraph 445Xpro up for grabs in Jersey City, NJ -- if you can come get it, it's yours. Nice monitor, heavy, it'll do 1920x1440 at a nice refresh rate (of course, see the previous 100 or so pages of this post for details on that) -- it's been on the floor for about 3 months and hasn't been powered on since, but it worked when it got disconnected. And hey, you can't beat the price on it! (Free) (if you can read this, it's still around -- I'll edit/delete when it goes)
 
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