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 Post subject: Re: Fudoh's ode to old display technology
PostPosted: Sat Oct 09, 2021 10:32 am 


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tongshadow wrote:
Converging by tilting the yoke vertically is useless anyways because there's only one position to get proper parallel (not straight!) horizontal lines.


I found when I had terrible convergence because of a poorly positioned yoke I also had at least a little bit of htrap distortion or so, so maybe you're right. It's probably rare to have a TV with perfect geometry but terrible convergence anyway.

bobrocks95 wrote:
Well, the picture's lovely as long as you only look at the middle of the screen where the static convergence is good lol. Don't think I could do without a high voltage regulator to stop bright colors from blooming at this point.

Wish I could find another since we did bang up the plastic getting it home (32" and heavier than it has any earthly right to be). But I don't think that'll ever happen.


You know they made 40" WEGAs? Must be >150Kg. It seems the truly high-end sets with all those PVM/Monitor like features are all >= 30", but I just can't carry or transport them without special arrangements and could at best fit one of them. I think 25" (is that 27" by US measurements?) is the sweet spot for me since I can just about get my arms around that kind of case.

Good point about the HV regulator. That's just what I mean with my comment one expectations with CRT TVs. Even if you have perfect geometry all it takes is a single bright spot to distort everything around it.

bobrocks95 wrote:
Quote:
I don't really know exactly what type of magnets / material are the right kind etc., I'm just trying things out and play around till the picture looks good :/


I tried what, a piece of a tin can I think once? Absolutely not the right material haha. I did find permalloy like sheets you could buy and cut, I think that'd be the ideal solution.


Josh128 wrote:
I bought some permalloy and cut it, it works.


The strips I've shown were just using permanent magnet tape, which is apparently the wrong material but can still be useful. From what I've read, box cutter blades should be permalloy. I made a few strips out of that but have yet to try them. And yeah, you can buy sheets of permalloy on eBay.

I honestly don't really know what exactly the point of putting a specific non-magnetized piece of metal near the yoke is. Permalloy is 'permeable', so I would assume that unlike lead etc. it lets the magnetic field from yoke go right through it? How would that help? I guess I could see if those strips were blocking/guiding the magnetism from the coils, but what is the point of something that neither has its own magnetism nor affects the existing one? If anybody here could clear that up for me, much appreciated :-)

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 Post subject: Re: Fudoh's ode to old display technology
PostPosted: Sat Oct 09, 2021 12:40 pm 


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Quote:
I honestly don't really know what exactly the point of putting a specific non-magnetized piece of metal near the yoke is. Permalloy is 'permeable', so I would assume that unlike lead etc. it lets the magnetic field from yoke go right through it? How would that help? I guess I could see if those strips were blocking/guiding the magnetism from the coils, but what is the point of something that neither has its own magnetism nor affects the existing one? If anybody here could clear that up for me, much appreciated :-)


Magnetic permeability of a material near a coil changes (increases) the coils inductance. This is the same principle all high efficiency transformers utilize and why they have an iron or ferrous core. These strips affect the magnetic field produced by the DY in the area under the coil in which they are placed. This affects how each cathode ray is deflected in that region of the tube. Permalloys super high permeability makes it effective even in thin strips required to slide under the yoke. That said, expect to be frustrated when using strips-- most of the time, you can only get limited benefits as a strip affects all the cathode rays, not just one. If your red is separated in the top right corner from your blue and green, they will all move when you play with a strip underneath them, which also affects geometry in that corner. By using different depths and angles of the strip, sometimes you CAN get corner convergence a bit better, but its often difficult, frustrating, limited, and not the magic bullet you might be hoping it is.

Also, despite what others have said, tilting the yoke does work for adjusting dynamic convergence, its actually the most effective way to do it when you dont have PVM-like adjustment coils and controls. Thing is, its like an art. Its ULTRA sensitive. You may need to tilt the yoke 1mm up, down, or diagonally to pull a red or blue extruding beam back into the white line where its supposed to be. THEN you have to place the wedge under it then tighten the clamp to hold the yoke there all without anything moving. THEN you have to re-examine other areas of the screen that you werent having a problem with to see if youve introduced a problem. In other words, its not easy. :mrgreen:


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 Post subject: Re: Fudoh's ode to old display technology
PostPosted: Sat Oct 09, 2021 1:42 pm 



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On my Sony PVM I had to remove the anti glare filter because it was damaged. Now I find the brightness to be much higher and the black levels are much worse. Does anyone know if it's possible to use a different anti glare filter from for example a car window?


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 Post subject: Re: Fudoh's ode to old display technology
PostPosted: Sat Oct 09, 2021 6:55 pm 


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I noticed on my flyback there's a SCREEN knob below the Focus. What does that do?


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 Post subject: Re: Fudoh's ode to old display technology
PostPosted: Sat Oct 09, 2021 7:15 pm 


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Increases or decreases screen voltage. ie it will brighten or darken the screen.


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 Post subject: Re: Fudoh's ode to old display technology
PostPosted: Sat Oct 09, 2021 7:55 pm 


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Josh128 wrote:
Increases or decreases screen voltage. ie it will brighten or darken the screen.

Ah ok. I don't need to mess with that then.

Ok I opened my set up today and attempted to adjust the yoke. I only loosened the screw a little (about a turn and a half) so the yoke doesn't move on its own. However all I can really do is rotate the screen, I'm not having much if any affect on the convergence other than making it slightly worse in the lower right corner. Do I need to loosen the screw more to actually move the yoke rather than simply rotating it or do I need to just be a bit more forceful? Part of my problem is I'm not 100% sure where to grab the yoke when I'm adjusting. The plastic ring has a wire around it for the built-in screen rotation adjustment so I'm afraid to grab that for fear of damaging it (although it looks pretty sturdy). I took two pictures of my yoke (see below), where should I grab it to do some serious adjustments?

I think I mentioned it before, but there's a second screw further back behind the convergence rings (you can see it in the second picture), do you think I need to loosen that to move the yoke around?

Spoiler: show
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 Post subject: Re: Fudoh's ode to old display technology
PostPosted: Sat Oct 09, 2021 9:12 pm 


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It looks like just the screw closest to the yoke, the second looks like its for that coil assembly on the neck. What kind of set is that? Also, I didnt see pictures of your problem, did you post a pic of a crosshatch?

Adjusting yoke tilt is for dynamic (non center) convergence after you have already gotten good static (center) convergence from adjusting the rings. The DY is probably "stuck" to the rubber wedges between it and the tube. You need to fully loosen that closest screw and back the yoke off of the wedges. You will then need to remove the wedge that is holding the yoke from tilting in the direction you want to adjust. You will then need to re-insert the wedge, tape it, and tighten the yoke.


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 Post subject: Re: Fudoh's ode to old display technology
PostPosted: Sat Oct 09, 2021 10:23 pm 


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Josh128 wrote:
It looks like just the screw closest to the yoke, the second looks like its for that coil assembly on the neck. What kind of set is that? Also, I didnt see pictures of your problem, did you post a pic of a crosshatch?

Adjusting yoke tilt is for dynamic (non center) convergence after you have already gotten good static (center) convergence from adjusting the rings. The DY is probably "stuck" to the rubber wedges between it and the tube. You need to fully loosen that closest screw and back the yoke off of the wedges. You will then need to remove the wedge that is holding the yoke from tilting in the direction you want to adjust. You will then need to re-insert the wedge, tape it, and tighten the yoke.

It's a KV27-FS100

I posted pictures a few posts back (previous page about a quarter of the way down), here they are again. It's the dynamic convergence that I need to fix. You're probably right in that I need to unstick it from the wedges. Hopefully I don't actually have to remove the wedges though.

Spoiler: show
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 Post subject: Re: Fudoh's ode to old display technology
PostPosted: Sat Oct 09, 2021 11:58 pm 


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Josh128 wrote:
It looks like just the screw closest to the yoke, the second looks like its for that coil assembly on the neck. What kind of set is that? Also, I didnt see pictures of your problem, did you post a pic of a crosshatch?

Adjusting yoke tilt is for dynamic (non center) convergence after you have already gotten good static (center) convergence from adjusting the rings. The DY is probably "stuck" to the rubber wedges between it and the tube. You need to fully loosen that closest screw and back the yoke off of the wedges. You will then need to remove the wedge that is holding the yoke from tilting in the direction you want to adjust. You will then need to re-insert the wedge, tape it, and tighten the yoke.

If I want to fix horizontal sagging on the bottom would I move the yoke left or right?


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 Post subject: Re: Fudoh's ode to old display technology
PostPosted: Sun Oct 10, 2021 2:37 am 


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Yes. Thats how its supposed to work.


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 Post subject: Re: Fudoh's ode to old display technology
PostPosted: Sun Oct 10, 2021 7:33 pm 


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So I was moving the yoke around to fix the geometry and the two wedges holding it in place fell out. Now I have this issue:

Spoiler: show
Image


I know where the one goes, it was right in the center on the top of the yoke and I have a picture of where it was. The second one however was on the upper right of the yoke (from the back about 2 o' clock) but that's all I really know. It doesn't seem to want to stay in anywhere now. Is my CRT screwed now or can this color distortion be fixed. I imagine this has something to do with the yoke being too far forward or backwards but I can't seem to figure it out. I just knew I was going to screw something up...

Help!

I also saw that there was a plug that wasn't plugged in. No idea if it was ever plugged in or not, I can't see anything obvious that it would go to. It's the one with the gray wires and one yellow wire on the left side of the first picture. The closest marking on the board says To V Board.

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 Post subject: Re: Fudoh's ode to old display technology
PostPosted: Sun Oct 10, 2021 7:57 pm 


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AH HA! I see it! It's on the neckboard! Maybe this is what's causing my problems? Which way does it go in? Yellow wire on top or bottom?

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 Post subject: Re: Fudoh's ode to old display technology
PostPosted: Sun Oct 10, 2021 8:19 pm 



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Tempest_2084 wrote:
I imagine this has something to do with the yoke being too far forward or backwards but I can't seem to figure it out.

Yea thats it, just a standard purity issue.


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 Post subject: Re: Fudoh's ode to old display technology
PostPosted: Sun Oct 10, 2021 8:30 pm 


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tongshadow wrote:
Tempest_2084 wrote:
I imagine this has something to do with the yoke being too far forward or backwards but I can't seem to figure it out.

Yea thats it, just a standard purity issue.


I think it's more than a standard purity issue, but like I said there's a cable that popped out the neck board that I'm trying to figure out how it goes in. Maybe that's causing some of the problems?


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 Post subject: Re: Fudoh's ode to old display technology
PostPosted: Sun Oct 10, 2021 9:13 pm 



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I have never worked on Sony TVs before but theres generally only 1 cable that goes to the neck of a CRT: the RGB output connection cable, which also can have pins for the heater voltage and 200V or so to drive the cathodes. On fancier sets there's also a cable for the velocity modulation circuit and another separate 3/4 pin cable for the VM coil itself (attached to the necktube itself). Disconnecting the latter shouldnt result in purity issues, and some even say it improves the picture, but it's a Sony and they use unique designs not seen anywhere else, like 2 separate boards on the tube's neck.


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 Post subject: Re: Fudoh's ode to old display technology
PostPosted: Sun Oct 10, 2021 9:49 pm 


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Got the cable back in (yellow on the bottom), but I think the set is hosed. No amount of adjusting the yoke is fixing the colors on the edges of the screen (or having any effect actually). I'm not sure what I'm doing wrong!


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 Post subject: Re: Fudoh's ode to old display technology
PostPosted: Sun Oct 10, 2021 10:07 pm 


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So this is where I'm at right now. I fixed the major color issue I was having (I just had to push the yoke forward until it popped into a groove or something), but as you can see I need to tweak the geometry and there's still some color purity issues on the left side. Which way do I move the yoke to fix that?

Spoiler: show
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 Post subject: Re: Fudoh's ode to old display technology
PostPosted: Sun Oct 10, 2021 11:11 pm 


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Its hard to say which way you need to move it. But it looks like you've definitely improved the lower dynamic convergence quite a bit over your original pictures here.

You likely are very close and just need to adjust the tilt by a single degree or fractions of a degree. Sometimes you can accomplish this type of fine adjustment by slowly sliding a wedge in, the thickness changes on the wedge will do the tilting for you. But it looks like you are definitely on the right track.


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 Post subject: Re: Fudoh's ode to old display technology
PostPosted: Mon Oct 11, 2021 12:30 am 


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Josh128 wrote:
Its hard to say which way you need to move it. But it looks like you've definitely improved the lower dynamic convergence quite a bit over your original pictures here.

You likely are very close and just need to adjust the tilt by a single degree or fractions of a degree. Sometimes you can accomplish this type of fine adjustment by slowly sliding a wedge in, the thickness changes on the wedge will do the tilting for you. But it looks like you are definitely on the right track.

That's a good idea. Right now I have no wedges in there at all. Currently I have the color on the left side of the screen fixed but when I move the yoke it tends to go back to being yellow. I have fixed the lower right corner but there's still done convergence issues on the bottom horizontal line.

Since I have it mostly there I'll tighten down the screw more and the move it very slightly until I dial it in.

It doesn't show in this picture but I'm having some linearity issues with the left side of the screen. The squares on the left are smaller (thinner) than the other squares. How do I fix that?


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 Post subject: Re: Fudoh's ode to old display technology
PostPosted: Mon Oct 11, 2021 8:13 am 


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Josh128 wrote:
Magnetic permeability of a material near a coil changes (increases) the coils inductance. This is the same principle all high efficiency transformers utilize and why they have an iron or ferrous core. These strips affect the magnetic field produced by the DY in the area under the coil in which they are placed. This affects how each cathode ray is deflected in that region of the tube. Permalloys super high permeability makes it effective even in thin strips required to slide under the yoke. That said, expect to be frustrated when using strips-- most of the time, you can only get limited benefits as a strip affects all the cathode rays, not just one. If your red is separated in the top right corner from your blue and green, they will all move when you play with a strip underneath them, which also affects geometry in that corner. By using different depths and angles of the strip, sometimes you CAN get corner convergence a bit better, but its often difficult, frustrating, limited, and not the magic bullet you might be hoping it is.


That's a great explanation, thanks!

I agree that it's a total PITA. This weekend I was trying to fix a corner that has red separated vertically and I just couldn't get it any better. Either I fix red and have blue bulging out or I have everything in alignment but now the entire corner is dragged upwards :/

I've made some more strips:

Image

both the permanent magnets and the permalloy ones from box cutter blades work fine and have useful effects.

Josh128 wrote:
Also, despite what others have said, tilting the yoke does work for adjusting dynamic convergence, its actually the most effective way to do it when you dont have PVM-like adjustment coils and controls. Thing is, its like an art. Its ULTRA sensitive. You may need to tilt the yoke 1mm up, down, or diagonally to pull a red or blue extruding beam back into the white line where its supposed to be. THEN you have to place the wedge under it then tighten the clamp to hold the yoke there all without anything moving. THEN you have to re-examine other areas of the screen that you werent having a problem with to see if youve introduced a problem. In other words, its not easy. :mrgreen:


My experience as well, it's very finicky. On newer Sony TVs there are dynamic convergence controls & coils on the top of the yoke and then there's also these magnet pieces that slide into the side. Even very old PVMs have these.

Touching the yoke is a PITA...

H6rdc0re wrote:
On my Sony PVM I had to remove the anti glare filter because it was damaged. Now I find the brightness to be much higher and the black levels are much worse. Does anyone know if it's possible to use a different anti glare filter from for example a car window?


Hm, can't get things looking proper with just the usual contrast/brightness controls? Might have to exercise some more light control in the room, but I haven't noticed any other adverse effects :/

Tempest_2084 wrote:
...


Those color issues were the purity issues I told you about, happens when you move the yoke too much forwards/backwards. You should really take pictures BEFORE you do stuff to your TV so you know where cables etc. were. Also did you read the service manual like I suggested? You have plenty of controls on your yoke and I think you got Y splitter magnet or whatever it was called, there's lot of useful things to be tweaked there!


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 Post subject: Re: Fudoh's ode to old display technology
PostPosted: Mon Oct 11, 2021 8:31 am 


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Advice needed - Can a TV degauss my magnet? :shock:

I had this Sony for a while, great condition, never really put it into rotation because of the very common corner of total fuckedness:

Image

It's actual worse than it looks. It's not just the corner, the entire upper-right part of the screen sags down and it's super noticeable when scrolling or when a straight line/box etc. is on the screen.

I originally tried to fix it by placing a small ferrite bar magnet close to the yoke. I was able to fix the sag of the horizontal lines but introduced all kinds of other issues like a curl of vertical lines near the top and a bow on the right screen edge.

This weekend I thought I give it another shot and removed all magnets, yoke strips etc. and see if I can fix it for good. After some hours of messing around and experimenting I figured out placing a stronger magnet further away from the yoke did a better job. It gently moved everything up a little without introducing too many other issues. Stuff close to the yoke is good for affecting a single small spot like a bit of a corner, further seems to be better for my issue. Here:

Image

(ignore some of the white tape, just added temporarily to mark location etc.)

After all that work geometry and convergence were looking decent:

Image
Image

Massive improvement and good enough for an FD Trinitron.

I then closed up the TV and gave it another go. To my great surprise, things were looking bad again. I opened up the TV, thinking I had accidentally dislodged something or the speakers in the back housing were causing issues etc. No luck, nothing had moved a millimeter and things still looked broken :/

Then it dawned on me that while adjusting the set I turned it on and off a couple of times to enter or leave the service menu, but if you do that quickly the degausser never fires. But it definitively had after turning it off for a while when reassembling it. If you look at the placement of my magnet, it's quite high and inside one of the two loops of the degaussing coil. I also noticed that when placing another new magnet directly where the installed one is my geometry mostly moves back to where it's supposed to be. Hm.

Do you think my theory of the TV degaussing my correction magnet is plausible? Can I just not place magnets that far away from the yoke, in the upper/lower area where the two coils on this set are placed?


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 Post subject: Re: Fudoh's ode to old display technology
PostPosted: Mon Oct 11, 2021 11:12 am 


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Depending on the makeup of the magnet its possible, but more likely is the scenario that you moved/rotated the TV after closing it up, causing a purity issue from the earths magnetic field.


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 Post subject: Re: Fudoh's ode to old display technology
PostPosted: Mon Oct 11, 2021 11:26 am 


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Josh128 wrote:
Depending on the makeup of the magnet its possible


Ferrite bar magnets?

If I add another magnet or two I can get things back to how they looked like before the degaussing happened, but then I guess those would just be degaussed as well.

I also quickly tried to just take the magnets off, now I have another issue. Seems like overnight the tube has taken magnetism from the correction magnets and I now have a big dent and some severe purity issues in that spot. If the sets build in degausser can't take care of this I think I need to buy an external degaussing coil. Oh boy.

Josh128 wrote:
, but more likely is the scenario that you moved/rotated the TV after closing it up, causing a purity issue from the earths magnetic field.


I think we can safely exclude that as the issue. I didn't move/rotate it any significant way during testing and reassembling and moving / rotating it a bit on the work table doesn't change anything, certainly nothing quite so big and confined to a single corner. The earth's magnet field might rotate the picture or maybe cause purity issues, but it does not cause anything like that.


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 Post subject: Re: Fudoh's ode to old display technology
PostPosted: Mon Oct 11, 2021 11:53 am 


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ASDR wrote:
I also quickly tried to just take the magnets off, now I have another issue. Seems like overnight the tube has taken magnetism from the correction magnets and I now have a big dent and some severe purity issues in that spot. If the sets build in degausser can't take care of this I think I need to buy an external degaussing coil. Oh boy.


Ouch. This is why I'm afraid to play with any magnets on my set other than those weak convergence strips. I hope there's no permanent damage because your geometry looks great. What pattern did you use to adjust it? I'm currently using the red/white grid, but people are telling me that I need an all white grid because the red hides convergence issues (and given my past convergence issues I agree).


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 Post subject: Re: Fudoh's ode to old display technology
PostPosted: Mon Oct 11, 2021 12:04 pm 



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Yes, purity magnets should be placed in the area where the internal magnetic shield (that gets degaussed like the mask) is not present (i.e. not too far away from the yoke) or their effect will vanish after degaussing.

https://i.imgur.com/TEbP6ba.jpg

Here's a view of a CRT innards showing the shield and its square cutout:

https://i.imgur.com/VedNx7k.jpg


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 Post subject: Re: Fudoh's ode to old display technology
PostPosted: Mon Oct 11, 2021 9:46 pm 



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ASDR wrote:
Hm, can't get things looking proper with just the usual contrast/brightness controls? Might have to exercise some more light control in the room, but I haven't noticed any other adverse effects :/


In a fully dark room I'm finding the black levels disappointing to be honest. In a room with the lights on it's even worse. On some of my CRT PC monitors the black levels are great. Could it be the SMTPE phosphors having worse black levels than P22 phosphors? Or could it be a wrong G2 voltage? Please note I have two PVM-20L4s both having the same disappointing black levels. I highly doubt G2 voltage is set wrong on both. Also both PVMs have low hours (less than 5.000).

I really hope an alternative anti glare filter could improve black levels but nobody seems to know what anti glare filter would be the best choice if any.


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 Post subject: Re: Fudoh's ode to old display technology
PostPosted: Mon Oct 11, 2021 10:06 pm 



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H6rdc0re wrote:
In a fully dark room I'm finding the black levels disappointing to be honest. In a room with the lights on it's even worse. On some of my CRT PC monitors the black levels are great.


That's almost certainly because any PC CRT you've used has dark anti-glare coating or film, since they were made for typical use in bright-lit work spaces. PVMs and such in turn were for light-controlled if not blacked-out rooms in mind, but it is true that even in those conditions the non-tinted tubes don't do great when it comes to contrast.

I don't know of any anti-glare filter you can buy that would be satisfactory. Everything I found when I looked into it had a shiny finish and added even more reflection, and although it did bring black levels down it did so at the cost of brightness loss that is difficult to compensate.


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 Post subject: Re: Fudoh's ode to old display technology
PostPosted: Mon Oct 11, 2021 11:01 pm 


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Someone in another forum suggested that I could adjust the three dials on the yoke to adjust the convergence. Does anyone know what these dials do exactly? They're marked VR1, VR2, and VR3.


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 Post subject: Re: Fudoh's ode to old display technology
PostPosted: Tue Oct 12, 2021 2:44 am 


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H6rdc0re wrote:
ASDR wrote:
Hm, can't get things looking proper with just the usual contrast/brightness controls? Might have to exercise some more light control in the room, but I haven't noticed any other adverse effects :/


In a fully dark room I'm finding the black levels disappointing to be honest. In a room with the lights on it's even worse. On some of my CRT PC monitors the black levels are great. Could it be the SMTPE phosphors having worse black levels than P22 phosphors? Or could it be a wrong G2 voltage? Please note I have two PVM-20L4s both having the same disappointing black levels. I highly doubt G2 voltage is set wrong on both. Also both PVMs have low hours (less than 5.000).

I really hope an alternative anti glare filter could improve black levels but nobody seems to know what anti glare filter would be the best choice if any.

just turn down the screen voltage, ez pz


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 Post subject: Re: Fudoh's ode to old display technology
PostPosted: Tue Oct 12, 2021 11:08 am 


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Tempest_2084 wrote:
Ouch. This is why I'm afraid to play with any magnets on my set other than those weak convergence strips. I hope there's no permanent damage because your geometry looks great. What pattern did you use to adjust it? I'm currently using the red/white grid, but people are telling me that I need an all white grid because the red hides convergence issues (and given my past convergence issues I agree).


It all worked out, don't be discouraged :-)

You need like all the patterns. The red grid of course has the issue that it hides red convergence issues. I find the fine grid is really good to adjust convergence and fine corner geometry and make sure the edges line up, but I also can't see 'larger scale' distortion on it. Basically, on the usual red grid you can make sure linearity is great and that overall there's no wobblyness, but it's very course so you can't see minor errors close to the edge or whatever falls between the grid lines. The linearity screen where you can add a grid and dots is also another great one. Basically, adjust stuff and look at 3-5 different screens. I have it all the time that I think I got a setting or magnet just right and then it looks like total crap on another pattern.

MKL wrote:
Yes, purity magnets should be placed in the area where the internal magnetic shield (that gets degaussed like the mask) is not present (i.e. not too far away from the yoke) or their effect will vanish after degaussing.

https://i.imgur.com/TEbP6ba.jpg

Here's a view of a CRT innards showing the shield and its square cutout:

https://i.imgur.com/VedNx7k.jpg


Perfect, just the info I needed.

H6rdc0re wrote:
In a fully dark room I'm finding the black levels disappointing to be honest. In a room with the lights on it's even worse. On some of my CRT PC monitors the black levels are great.


Hm, I have to admit that I only ever had to remove the screen/foil from a PC CRT and my PVMs either never had them or had them already removed, so I'm not sure. On my PC CRT it was no big deal, quick readjust and light control. But like others have said, PVMs often have these very grey screens, they were clearly made for professional environments with ambient light control.

Tempest_2084 wrote:
Someone in another forum suggested that I could adjust the three dials on the yoke to adjust the convergence. Does anyone know what these dials do exactly? They're marked VR1, VR2, and VR3.


I'm always yelling about them! :-) And the service manual! It should tell you what these do, probably TLV, YCH and HTRAP (there's a picture explaining what these are in basically every service manual). The service manual also has schematics that'll tell you where unplugged cables are supposed to go, it'll say something like 'To DY' or 'To D board'.

Tempest_2084 wrote:
Josh128 wrote:
Increases or decreases screen voltage. ie it will brighten or darken the screen.

Ah ok. I don't need to mess with that then.


Maybe. If G2/Screen is set wrong this can also cause issues like visible retrace lines and just below that some kind of effect that looks like focus is wrong. I'd give it a quick adjust.


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