Fudoh's ode to old display technology

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fernan1234
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Re: Fudoh's ode to old display technology

Post by fernan1234 »

bobrocks95 wrote:Can't find exactly how old it is but it has a fluorescent backlight so sounds pretty old to me. If it does have a fast response time, it's probably because it has a TN panel with horrible viewing angles and very poor contrast. Even with an IPS, VA, or some other variant LCD panel, any LCD tech has improved drastically since then and I don't see how these displays would be worth having at all.
You'd be surprised. These were top of the line LCD displays at the time and for good reason. Pixel response time was very fast to the point where motion blur was hardly a problem, and on top of that as mentioned above they also have BFI which reduces persistence blur that all flat panels have otherwise. Their color is indeed very accurate and they also have a wide viewing angle (not that it matters much unless we're talking about the larger 32'' models).

The only problem is that at this point most are not only very old but also very used, and they are prone to developing aging problems with stuck pixels, backlight bleeding, and such. If you can find one in good performing state for a low price they 100% beat most consumer options available today, at least for SD content.

xeos wrote:The native scan mode sounds interesting, but... Wouldn't that be very similar visually to what the OSSC produces when you use alternating 100% black scanlines for 480i content? In my experience the interlacing artifacts are quite visible in this mode; in essence it's close to the "lace" deinterlacing method because LCDs can't turn a pixel black instantly. Perhaps the LMD-2300 has ultra fast response time to address this?
Yeah it's exactly alternating black lines in between the fields like the OSSC and Retrotink's "CRT simulate" mode can do. The combination of the particular response time speed of these panels makes this effect work very well though, producing a highly CRT-like interlaced picture (also for 1080i). Not the same as a "lace" method though.

Note that this is a feature of the PVM models, and not available on the inferior LMD models.

The interlaced mode only works when native scan is enabled (which presents the picture pixel matched for SD and 720p, or x2 integer scaled for SD). Since the panels are 120Hz, they can do BFI by simply blacking out every other frame.

The BVM LCDs also had all these features and are better monitors. The later OLED models do as well, which are of course vastly superior monitors (and instead of BFI they use a scanning bar which is more effective, and they also lose no brightness from it).
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Tempest_2084
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Re: Fudoh's ode to old display technology

Post by Tempest_2084 »

What's everyone's opinion on the Toshiba CZ27T31? There's an RGB modded one for sale near me with really nice geometry but it the focus/convergence appears off in the corners. It also doesn't have S-Video so its composite only plus the RGB mod. I have some people telling me that I won't notice the blurry corners when playing a game, but from the picture it looks really bad. Not sure if playing with the focus knob would fix that or not. I've been told that Thomson tubes are just like this.
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KPackratt2k
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Re: Fudoh's ode to old display technology

Post by KPackratt2k »

That Toshiba looks exactly like the TV my family used to have before we moved to Seattle.
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bobrocks95
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Re: Fudoh's ode to old display technology

Post by bobrocks95 »

Tempest_2084 wrote:What's everyone's opinion on the Toshiba CZ27T31? There's an RGB modded one for sale near me with really nice geometry but it the focus/convergence appears off in the corners. It also doesn't have S-Video so its composite only plus the RGB mod. I have some people telling me that I won't notice the blurry corners when playing a game, but from the picture it looks really bad. Not sure if playing with the focus knob would fix that or not. I've been told that Thomson tubes are just like this.
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In my experience working on my consumer set, you either get static convergence (center of the screen) perfect, dynamic convergence (edges of the screen) perfect, or have them both equally off. My FV310 has tons of adjustments, but nowhere near what a BVM has available digitally in its service menu. Every setting you can change or knob you can turn or magnet you can move makes one thing or spot look a bit better while another starts looking a bit worse. What's there becomes a game of push and pull, "good enough" sort of calibration where you eventually have to call it and stop fiddling with the thing.

All that said I've definitely seen worse convergence. The sorts of things I notice bad dynamic convergence on the most is white HUD elements with straight lines near the edges of the screen. Past that it's more a fuzzy look that isn't that noticeable when you aren't actively looking for it.
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Tempest_2084
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Re: Fudoh's ode to old display technology

Post by Tempest_2084 »

bobrocks95 wrote:
Tempest_2084 wrote:What's everyone's opinion on the Toshiba CZ27T31? There's an RGB modded one for sale near me with really nice geometry but it the focus/convergence appears off in the corners. It also doesn't have S-Video so its composite only plus the RGB mod. I have some people telling me that I won't notice the blurry corners when playing a game, but from the picture it looks really bad. Not sure if playing with the focus knob would fix that or not. I've been told that Thomson tubes are just like this.
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In my experience working on my consumer set, you either get static convergence (center of the screen) perfect, dynamic convergence (edges of the screen) perfect, or have them both equally off. My FV310 has tons of adjustments, but nowhere near what a BVM has available digitally in its service menu. Every setting you can change or knob you can turn or magnet you can move makes one thing or spot look a bit better while another starts looking a bit worse. What's there becomes a game of push and pull, "good enough" sort of calibration where you eventually have to call it and stop fiddling with the thing.

All that said I've definitely seen worse convergence. The sorts of things I notice bad dynamic convergence on the most is white HUD elements with straight lines near the edges of the screen. Past that it's more a fuzzy look that isn't that noticeable when you aren't actively looking for it.
I know what you mean. I have a Kv-27fs100 that I've been adjusting on and off for years now and every time I think I have it where I want it something else goes wonky. I'm actually looking at this as a potential replacement for it since my Trinitron has some bad convergence issues on the left and right sides plus it has a weird horizontal linearity issue I've never been able to fix. Maybe if I can make the corners less blurry (at the cost of done sharpness in the center) it might be a decent replacement. Or maybe I should just hold out for something better since I'm not in a hurry. I'd just never heard of this model before and was wondering if it was something decent or not. The lack of S-Video is annoying and makes me wonder if this isn't a lower end set.
cfx
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Re: Fudoh's ode to old display technology

Post by cfx »

Definitely not an upper model, as those had side speakers instead of the small ones on the bottom. Toshiba also tended to make the higher models silver rather than black.
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Re: Fudoh's ode to old display technology

Post by KPackratt2k »

Tempest_2084 wrote:The lack of S-Video is annoying and makes me wonder if this isn't a lower end set.
I guess modding the set to include an S-Video input is a possibility. If you don't want to do this (and I understand if you don't as CRTs can be dangerous to work inside on if you're not experienced enough), then an external S-Video to RGB decoder box should fill that gap.

Assuming this set uses a Toshiba jungle chip (which a lot of Toshiba TVs did prior to being rebranded Orion sets), it may be as simple as injecting Luma into Composite and Chroma into the Chroma input pin of the jungle chip, as I've seen an S-Video mod being done in this manner on another TV that used one of those chips.
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Tempest_2084
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Re: Fudoh's ode to old display technology

Post by Tempest_2084 »

cfx wrote:Definitely not an upper model, as those had side speakers instead of the small ones on the bottom. Toshiba also tended to make the higher models silver rather than black.
Yeah although I'm tempted as he's close and the geometry looks good, I think I might pass on this one. I know people say that you can never get really good convergence and focus in the corners of these 27"+ sets, but I've seen much better than this. Even if adjusting the focus knob fixes the extreme fuzziness in the corners (the diamond shapes are practically blobs in the upper left) I think the convergence issues are a deal breaker. It's hard to tell how bad they are with the fuzziness at the moment but I'm seeing them all along the top and sides.

I guess my hunt continues. Thanks for the input everyone. If someone has a nice 27" curved TV with component or RGB mod in SE Michigan area that they want to sell or trade, shoot me a PM.
Derf
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Re: Fudoh's ode to old display technology

Post by Derf »

wwse wrote:Hello everybody
I am searching for BVM A14F5U service manual. If you has it please contact me in pm.
Thank you
Posted this morning by Onehunatacos:

https://www.consolemods.org/wiki/CRT:BVM-A14F5U
Ikaruga11
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Re: Fudoh's ode to old display technology

Post by Ikaruga11 »

Is the Extron DVI-RGB 200 or the HD Fury X4/X3 better for converting HDMI to VGA in regards to picture quality (accuracy, color, sharpness, lack of noise, etc.) and display lag? Can't decide between the two. I'm going to use the MiSTer FPGA with Direct Video at 240p, along with other consoles that do 240p/480i, 480p, 720p and 1080i.
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Re: Fudoh's ode to old display technology

Post by wwse »

Derf wrote:
wwse wrote:Hello everybody
I am searching for BVM A14F5U service manual. If you has it please contact me in pm.
Thank you
Posted this morning by Onehunatacos:

https://www.consolemods.org/wiki/CRT:BVM-A14F5U
Thank you!
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wwse
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Re: Fudoh's ode to old display technology

Post by wwse »

Does Sony BVM D24E1WE have a protective layer on the screen?
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kitty666cats
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Re: Fudoh's ode to old display technology

Post by kitty666cats »

Ikaruga11 wrote: Wed May 03, 2023 9:21 pm Is the Extron DVI-RGB 200 or the HD Fury X4/X3 better for converting HDMI to VGA in regards to picture quality (accuracy, color, sharpness, lack of noise, etc.) and display lag? Can't decide between the two. I'm going to use the MiSTer FPGA with Direct Video at 240p, along with other consoles that do 240p/480i, 480p, 720p and 1080i.

After extensive testing with an Oscilloscope, extensively staring at the screens of his pro monitors with a magnifying glass & testing the color voltages of video levels (at what the proper voltages should be per intensity of each color level) , Kuro Houou has determined the HDFury 3 is the most accurate DAC.

Some people on this board have claimed to see some ghosting on theirs, but it may be possible that they were using older revisions. Everyone in this CRT-dedicated Discord I use find the HDFury 3 to be by FAR the best HDMI to VGA as far as color accuracy goes. However, they are pretty damn expensive... you can find them on eBay used for decent prices every now and then, but even those listings are often $50+. I've heard the Extron DVI-RGB units are also a pretty solid choice, and can definitely found for way cheaper.

TBH, you probably wouldn't see a particularly large difference between those two if you have a VERY discerning eye. I adore my HDFury 3, but the Extron one won't definitely won't dissatisfy you. The only thing is, I'm not certain about the Extron one supporting 240p/480i. Probably does? But I haven't seen anyone verify for certain. That one clearly outputs RGBS composite sync, but the HDFury also will as long as you have the MiSTer output configured for RGBS :)


Here's an in-depth comparison between many, many DACs, their varying types of chipsets used, and the quality of their video output/black crush/detail integrity etc:

https://docs.google.com/document/d/1Fz3 ... 2nlbp9r33g

Hopefully you're satisfied with whichever choice you make!
kamiboy
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Re: Fudoh's ode to old display technology

Post by kamiboy »

Can someone who actually knows this for a fact tell me what kinds of image quality problems are typically caused by a CRT with out of spec capacitors? Not looking for speculations and hearsay, I got enough of that from googling.

The thing is I have a PVM 2730, and I am not exactly too thrilled about the image quality. I used to have more mint unit of the North American model 2530, and though it was over 10 years ago I could swear I was much more impressed by the image quality on that one. Either that is rose tinted glasses doing its magic or the one I currently got is not living up to its potential.

From what I can gather the number of TV lines on the PVM 2730 should be roughly equivalent to a 20L2. Now, I do own a 14L2 which to my eyes has the best CRT image quality I have personally witnessed, it is just beautiful. The two things the 14L2 has going against it is the tiny size, and the fact that unlike the PVM 2XX0 series, their chassis are an eyesore, so I don't want them out in the open. The PVM 2730 on the other hand is just an aesthetically attractive model.

As such I am starting to wonder whether I could do anything to bring the image quality of the 2730 closer to the L2. Perhaps the difference is due to the 2730 being more worn, or perhaps that the 2730 is an older generation PVM and despite the advertised TV lines it simply just cannot measure up to an L2. The third option is that perhaps the 2730 has some caps that are going out of specs which is why it is not as sharp as it could be.

In particular the L2 has more vibrant colours, but more importantly more defined scanlines than the 2730. The lack of scanline definition makes the 2730 look more blurry to my eyes, which I don't care so much for. It doesn't look like what I associate with a good trinitron set. So, can anyone confirm that out of spec capacitors could cause a blurrier image on such a CRT? Or do such issues just manifest in bad geometry, I read conflicted reports.

The 2730 is not exactly easy to work on and I am not keen on rolling up the old sleeves to do a partial, or gods forbid, a full recap unless I am certain it could potentially net me the results I am looking for.
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Re: Fudoh's ode to old display technology

Post by SuperSpongo »

Have you tried adjusting the focus?
If a monitor is blurry, my first guess would not be old caps, to be honest. More like worn tube, as you also said that the L2's picture is more vibrant and it has more pronounced scanlines.
I don't suppose you have access to a tube tester / rejuvenator?
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Re: Fudoh's ode to old display technology

Post by kamiboy »

A worn tube is one scenario I did consider, and might very well be the case since I have no information on the history of this tube, the TV is what, 25 years old, so it would be a small miracle if it is not worn. If it is worn though, then fiddling with focus is not going to do anything, that adjustment is not something that is likely to veer off on its own in a way that can be dialed back, right?

So, it is either worn tube, which cannot really be done anything about, or it could be capacitors, if those can cause such issues, which I could do something about.

In regards to the dark art of CRT rejuvenation, from what I have seen of people playing around with it, it seems overall not to be worth the effort, if a tube is so worn that it has come to that, it might just as well be binned.
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Josh128
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Re: Fudoh's ode to old display technology

Post by Josh128 »

I dont know for certain, but to my understanding, a "worn CRT" can mean a few different things:

1.) The cathodes/guns are worn, and dont emit as many electrons when fired as they did when new, resulting in a dimmer image.

2.) The screen phosphors are worn, and that results in either a dimmer image and/or faded/distorted colors.

3.) A combination of the above.

Neither of the above should technically result in a blurrier image / less focus, I believe. If so, I dont understand the mechanism of why that could be. More likely it should be due to issues with the screen and G2 voltages for vertical sharpness and the video amplfier circuitry for horizontal focus/ smearing. Vertical deflection "jitter" could also be a culprit.

Im currently looking to recap the neckboard on my XS955 because it doesnt look as sharp as I think it should be, mainly on a horizontal axis, so Im hoping its something with the turning on and off of the RGB guns, which is handled by the RGB drive amplifiers.
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vol.2
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Re: Fudoh's ode to old display technology

Post by vol.2 »

Josh128 wrote: Thu Jan 11, 2024 5:22 pm Neither of the above should technically result in a blurrier image / less focus, I believe. If so, I dont understand the mechanism of why that could be.
Yes they do. Especially if the Phosphors are broken down chemically, but also if the cathode isn't emitting as strongly. What happens is that the normal voltage you use for screen brightness isn't enough, so in order to get a viewable image, you have to crank the voltage up, and the higher voltage blows out the image. You can think about the phosphors as having an optimal voltage level to be "excited" to emit their color

If ideal focus occurs at a dimmer setting, chances are it's the tube. In order to determine this, you have to setup the TV properly first. It is old, so things have drifted. In a pitch black room, turn the contrast (picture) all the way up and then set the brightness at the halfway point. Then adjust the screen pot until your raster just barely goes pitch black, or is right on the edge of it. Then turn the contrast back to the halfway point

At this point, you might want to color balance the set as it has probably drifted as well, and you can usually get more headroom out of a balanced set

In any case, once you have the brightness set, throw up a white box on a black background pattern, and adjust the contrast as high it will go before the white box starts to grow in size. That's the point at which the image is blowing out. You can then throw up a focus pattern and adjust the focus pot for maximum focus, then do the white box and contrast again and repeat at least one more time

by the end of that, you should know if the tube is having issues. It's not necessarily a death sentence though, you can often "clean" a tubes cathodes with a rejuve device. If the tube gets gunk on the cathodes, it will inhibit electron emission and give you the symptoms of a very old/tired tube. Generally speaking, only sets that were really left on all day for decades are actually worn out. Although it's very possible a TV station set was left on 24-7 for 10 years straight

It's not completely impossible for caps to out of spec, especially in the power supply area that could have an effect on all of this stuff, but it's not something that I've personally seen a lot of, or heard a lot about on forums.
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Re: Fudoh's ode to old display technology

Post by xeos »

kamiboy wrote: Thu Jan 11, 2024 7:42 am In particular the L2 has more vibrant colours, but more importantly more defined scanlines than the 2730. The lack of scanline definition makes the 2730 look more blurry to my eyes, which I don't care so much for. It doesn't look like what I associate with a good trinitron set. So, can anyone confirm that out of spec capacitors could cause a blurrier image on such a CRT? Or do such issues just manifest in bad geometry, I read conflicted reports.
Sure sounds like convergence to me (aka geometry). IDK but I would assume that's completely unrelated to caps.

What I've noticed with older sets that have seen a lot of use is the grays become black (aka black crush) ruining all shadow detail. But I only acquire consumer sets, maybe the pro equipment handles this better.
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Re: Fudoh's ode to old display technology

Post by vol.2 »

xeos wrote: Thu Jan 11, 2024 7:42 pm What I've noticed with older sets that have seen a lot of use is the grays become black
Only if the contrast can't be raised any higher due to loss of focus.

The exact appearance of focus issues and convergence issues are different. Focus problem is a properly converged but "fuzzy" picture. Convergence issues can result in fuzziness, but you typically see a problem with lines not overlapping properly when you look at a crosshatch pattern. That's easy enough to rule out

Geometry isn't the same as convergence, although they have an effect on each other. Geometry controls are going to effect the shape of the image overall. Convergence effects how the lines overlap each other. It's the difference between how the 3 guns are adjusted in relationship to each other VS the way that all 3 of them are adjusted together to properly hit the tube at the right spots
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Re: Fudoh's ode to old display technology

Post by xeos »

vol.2 wrote: Thu Jan 11, 2024 8:25 pm
xeos wrote: Thu Jan 11, 2024 7:42 pm What I've noticed with older sets that have seen a lot of use is the grays become black
Only if the contrast can't be raised any higher due to loss of focus.
Fair point about the convergence and geometry being separate (though in fairness geometry problems usually cause convergence issues). But I don't agree with this claim. Raising the contrast often makes black crush worse. Perhaps we are using the term differently. I'm talking about the bottom 10-15% of the luminance curve being mapped to black. Reducing the contrast sometimes helps, actually. But usually nothing helps much, including messing around with the hidden configuration menu that some late model Sony consumer TVs have. I've discarded 3-4 CRTs because of this issue in the last decade. Discarded as in passed on to somebody else less obsessive about good image quality, that is.
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Re: Fudoh's ode to old display technology

Post by vol.2 »

xeos wrote: Thu Jan 11, 2024 9:15 pmBut I don't agree with this claim. Raising the contrast often makes black crush worse. Perhaps we are using the term differently. I'm talking about the bottom 10-15% of the luminance curve being mapped to black. Reducing the contrast sometimes helps, actually. But usually nothing helps much, including messing around with the hidden configuration menu that some late model Sony consumer TVs have. I've discarded 3-4 CRTs because of this issue in the last decade. Discarded as in passed on to somebody else less obsessive about good image quality, that is.
On an LCD monitor, the "contrast" actually effects image contrast, or the difference between the darkest part of the screen and the brightest part of the screen. On a CRT "contrast" does not do that at all, but is the white point of the image. Basically it raises the intensity of the image as drawn.

On a CRT the "brightness" is the black point; turning it up will have the effect of raising the brightness of the whole raster. There is always going to be a "correct" spot to adjust the brightness to, as it will start to make the screen glow grey if you turn it up too high

The "crush" you experience happens because, when the tube ages and gets dimmer, you lose dynamic range between the black point and the white point. You can't "get it back" by raising the contrast, but you should be able to adjust where the crush happens, ie by raising the brightness to an unacceptable level, you should be able to trade black crush for white crush at the top
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Re: Fudoh's ode to old display technology

Post by Josh128 »

vol.2 wrote: Thu Jan 11, 2024 7:12 pm
Josh128 wrote: Thu Jan 11, 2024 5:22 pm Neither of the above should technically result in a blurrier image / less focus, I believe. If so, I dont understand the mechanism of why that could be.
Yes they do. Especially if the Phosphors are broken down chemically, but also if the cathode isn't emitting as strongly. What happens is that the normal voltage you use for screen brightness isn't enough, so in order to get a viewable image, you have to crank the voltage up, and the higher voltage blows out the image. You can think about the phosphors as having an optimal voltage level to be "excited" to emit their color

If ideal focus occurs at a dimmer setting, chances are it's the tube. In order to determine this, you have to setup the TV properly first. It is old, so things have drifted. In a pitch black room, turn the contrast (picture) all the way up and then set the brightness at the halfway point. Then adjust the screen pot until your raster just barely goes pitch black, or is right on the edge of it. Then turn the contrast back to the halfway point

At this point, you might want to color balance the set as it has probably drifted as well, and you can usually get more headroom out of a balanced set

In any case, once you have the brightness set, throw up a white box on a black background pattern, and adjust the contrast as high it will go before the white box starts to grow in size. That's the point at which the image is blowing out. You can then throw up a focus pattern and adjust the focus pot for maximum focus, then do the white box and contrast again and repeat at least one more time

by the end of that, you should know if the tube is having issues. It's not necessarily a death sentence though, you can often "clean" a tubes cathodes with a rejuve device. If the tube gets gunk on the cathodes, it will inhibit electron emission and give you the symptoms of a very old/tired tube. Generally speaking, only sets that were really left on all day for decades are actually worn out. Although it's very possible a TV station set was left on 24-7 for 10 years straight

It's not completely impossible for caps to out of spec, especially in the power supply area that could have an effect on all of this stuff, but it's not something that I've personally seen a lot of, or heard a lot about on forums.
Ive gone through a similar sequence on my XS955 already, and variations of LukeEvansSimons sharpness "hack". I dont necessarily think theres anything wrong with the phosphors as I dont see any evidence of burn in or discoloration whatsoever, but its possible the guns could use a rejuv. There is definitely a slow vertical jitter though, and from what Ive gathered that can usually be remedied by recapping the deflection section. I do suspect that the set sat in some old couples house and just stayed on for eternity while they smoked cigarettes in the same room, as it was the nastiest piece of electronics Ive ever witnessed when I opened it up. No way that kind of smoke residue and tar makes it in there in just a couple of years.

But, brightness definitely seems limited vs what I would expect it to be, and turning up brightness / picture too much colors begin to bleed to the right, reds first, in particular. I dont know, I might just be expecting too much. This was supposed to be the ultimate CRT in my mind...

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Re: Fudoh's ode to old display technology

Post by vol.2 »

Josh128 wrote: Thu Jan 11, 2024 11:07 pm There is definitely a slow vertical jitter though, and from what Ive gathered that can usually be remedied by recapping the deflection section.
Yes, that would indicate the vertical section might need attention. It could also just need to have all of the pots cleaned and lubed or both. Especially if you suspect it sat in a smoking house, the tar can get inside the set and gunk up any non sealed pots and switches.

But the vertical tends to run fairly hot in most sets, so any electrolytics close to the V output IC will often dry out from the heat. Should be easy to just swap out those (what is probably 3-6) caps and see if it goes away.
But, brightness definitely seems limited vs what I would expect it to be, and turning up brightness / picture too much colors begin to bleed to the right, reds first, in particular. I dont know, I might just be expecting too much.
The sharpness mod, IIRC is basically just getting the beam to focus tighter. I suppose there might be some headroom to gain by increasing the amount of focus voltage you have at your disposal, but I've never tried it before. If you're not seeing any difference (ability to crank the contrast up without blooming), then I guess not in your case?

If you're interested in the rejuve process, check this out.
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Re: Fudoh's ode to old display technology

Post by kamiboy »

Perhaps I am expecting too much from a 2730/2530 though. I should mention that when I bought this I also threw in a 2130 from the same seller in the bargain and to my eyes the picture quality on it is in the same ballpark.

Has anyone had the chance of viewing an L2 and 2X30 in similar condition side by side to compare their image quality? Perhaps TVL being close on paper is not an accurate representation of how close the image quality on the two can be expected to be and the 2X30 series is just a step down from the L2 series.

I know the L2 has superior deflection circuits that lend themselves to better geometry overall, perhaps this also means the image quality is sharper overall with more defined scanlines.
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Re: Fudoh's ode to old display technology

Post by vol.2 »

It's kind of hard to know just based on how bright you think it looks. I usually hook up a colorometer like an Xrite from the early 2000s and just test the white point. If you max out the white point and it's still dim (like significantly under 100 nits) then you know you have a brightness issue. If it happily goes to ~80-100 nits then it's fine and you're just forgetting how dim CRTs are compared to the latest and greatest ultra-hyper-led-oled panel
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Re: Fudoh's ode to old display technology

Post by SuperSpongo »

kamiboy wrote: Thu Jan 11, 2024 3:55 pm So, it is either worn tube, which cannot really be done anything about
This model in particular did not have that special of a tube installed (A64JKJ10X). It can be found in a couple of consumer models as well. I recently learned that the 2130 and 2730 were even advertised as prosumer sets in Sony stores and catalogues back in the day in Germany:
https://www.hifi-archiv.info/Sony/1988-89/ page 42

So a tube swap is not out of the question as opposed to, say, a 2950.
That being said, a tube swap on this set sounds like a nightmare, being as crammed as it is :D
kamiboy
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Re: Fudoh's ode to old display technology

Post by kamiboy »

Hmmmm... Interesting. I guess my ultimate CRT would be whatever tube is in the L2 series in the enclosure of the 2X30 series. However, even if that was possible, it is not really anything I want to mess with, if it even is possible.

Not to mention that the L2 series only goes up to 20", and the difference in size between a 20" and a 25" is quite palpable, I feel 25" is in the sweet spot for a CRT, but 20" is just a tad too small. Perhaps I will keep an eye out for a 20" L2 in the future. I have some ideas as so how to do something about the ugly exterior of that otherwise magnificent series.
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vol.2
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Re: Fudoh's ode to old display technology

Post by vol.2 »

SuperSpongo wrote: Mon Jan 15, 2024 8:42 am
This model in particular did not have that special of a tube installed (A64JKJ10X). It can be found in a couple of consumer models as well. I recently learned that the 2130 and 2730 were even advertised as prosumer sets in Sony stores and catalogues back in the day in Germany:
The whole 2XXX line's tubes can be found in the XBR sets of the 90s IIRC.
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Re: Fudoh's ode to old display technology

Post by SuperSpongo »

Well, like I said, not the 2950. Can't speak for the US market but in Europe, only one consumer set was fitted with that tube and even that model was quickly revised and the tube was replaced in the process.
But I would not consider the 2950 to be part of the same lineup as the 2130 (2030), 2730 (2530) and 3230 anyways.
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