CRT Fetish Thread

Dochartaigh

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Tempest, generally speaking if something isn't symmetrically flawed (as in the left AND right side, or top AND bottom, or top left AND top right etc.) some caps could be going bad, or a magnet or convergence strip needs to be tweaked to fix something like that. Yours also has that weird bleed on the right-most edge where the horizontal lines are bleeding outside of the bounds of the grid - that's usually caps as well (or at least that fixed one of mine like that).

I would also adjust your grid like the below image. You want a little bit of the red going off the viewable area of the screen - that's the overscan area. Mine is even shifted to the right a little bit which gives me the best image for a variety of 240p systems (Genesis in particular likes to go to the right a little bit, so when it's adjusted like that my NES, TG16, SNES, Genesis, Saturn, and PS1 all display decently on the same monitor). This can also help hide some of the funky stuff that commonly goes on the outside edges which you normally wouldn't see on a consumer TV with similar built-in overscan adjustments.

kor0Zr3.jpg
 

Tempest

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Which system were you using as your baseline system for the grid? I was using my snes.
 

Dochartaigh

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Which system were you using as your baseline system for the grid? I was using my snes.

I always use SNES as well, then run the 240p test suite for NES and Genesis too (have it for DC and Wii too but that's usually for 480p). It's usually then good for every 240p system I own with pretty good overscan for all those systems.
 

Tempest

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Tempest, generally speaking if something isn't symmetrically flawed (as in the left AND right side, or top AND bottom, or top left AND top right etc.) some caps could be going bad, or a magnet or convergence strip needs to be tweaked to fix something like that. Yours also has that weird bleed on the right-most edge where the horizontal lines are bleeding outside of the bounds of the grid - that's usually caps as well (or at least that fixed one of mine like that).

I would also adjust your grid like the below image. You want a little bit of the red going off the viewable area of the screen - that's the overscan area. Mine is even shifted to the right a little bit which gives me the best image for a variety of 240p systems (Genesis in particular likes to go to the right a little bit, so when it's adjusted like that my NES, TG16, SNES, Genesis, Saturn, and PS1 all display decently on the same monitor). This can also help hide some of the funky stuff that commonly goes on the outside edges which you normally wouldn't see on a consumer TV with similar built-in overscan adjustments.

You think it could be the caps? The TV is from 2006, that seems a little early for caps to start failing. If it's the magnets or strips on the sides there's no way I'm fiddling with that as you can really do some damage if you don't know what you're doing. I think some of the blurriness on the sides is just due to the tube, these slimfit models are notorious for crappy convergence on the sides of the image. Then again, unless there's tiny text there you really don't notice it.

So which systems display a little to the right or underscan more than others (assuming we're using the SNES as the base system)? I have just about every system from the NES on up hooked up via RGB so I'm curious as to how I should adjust things to get the best positioning in general for all systems. The Neo Geo is a lost cause because the sides are so wide, unless I want to severely underscan all the other systems. Since you also have many different systems hooked up to your TV, can you share your thoughts on the positioning/sizing and or any thing else I should know?

NES
SMS
SNES
Genesis/32X
TurboDuo
N64
Xbox
PSX
PS2
Saturn
Dreamcast
Neo Geo
 

wyo

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Here are two shots of the Neo Geo. As you can see the cross hatch test is way off on the sides but there's also a weird distortion in the vertical lines on the top row. Not sure what that indicates

That indicates...you are using a CRT ;)
 

GohanX

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I've had Neo systems that didn't sync quite right do all kinds of funky things a the top of the screen, but it didn't look exactly like that.

Also, caps being a problem in 2006ish sets isn't unusual. Wega TVs in particular from that time period usually need caps. The inside of a CRT isn't exactly the most hospitable environment.
 

Tempest

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Huh I never would have guessed. Well I don't think I'll be recapping this beast myself and sending it out is out of the question so I'll just deal.
 

NEgO MANIAC

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Finally received my RGB cables and it looks great on the PVM. The only complaint that I have are light blue horizontal lines on the screen. They are only visible during dark color images. Plus my brightness adjustment isn’t very reactive. My guess is to adjust the flyback or possibly a cap kit. Any thoughts?
 
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GohanX

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Huh I never would have guessed. Well I don't think I'll be recapping this beast myself and sending it out is out of the question so I'll just deal.
I'm in that boat too with my Wega. I'm not gonna recap it, and there aren't any local shops that can do the work anymore so I'll just live with it.
 

Tempest

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I'm in that boat too with my Wega. I'm not gonna recap it, and there aren't any local shops that can do the work anymore so I'll just live with it.

That's the thing, no one does TV repair anymore. At least not CRT TVs. Depending on where the caps are and if they're on an easily removed board, I suppose you could send it out but I'm guessing they're on a high voltage board or something major. Either way, messing around in the back of a 27" CRT is a good way to get zapped if you don't know what you're doing.
 
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ChuChu Flamingo

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What causes this problem? From reading up replacing caps in the deflection circuit/power supply would fix this. This is a 32 inch JVC. My Commodore 1702 does this as well. I plan to recap that anyhow. It does it on the left side as well.

qVTbKFY.jpg




I plan to replace all the electrolytic capacitors in here since it needs it. The thing was caked in aids dust and also has weird sync jitter on 240p kinda like pulsing/video noise. I've seen this sync jitter before on other tvs. I assume perhaps some capacitor is out of spec.

Also bleeds blue if contrast is too high. White balance adjustment is kinda pointless to do if I plan on replacing the caps first.

A shame the service manual doesn't list them so I'll have to manually write them down

That's the thing, no one does TV repair anymore. At least not CRT TVs. Depending on where the caps are and if they're on an easily removed board, I suppose you could send it out but I'm guessing they're on a high voltage board or something major. Either way, messing around in the back of a 27" CRT is a good way to get zapped if you don't know what you're doing.

It is relatively safe to be working on a crt and take the board out as long as you discharge the monitor. Also be mindful of the psu capacitors. I open ever CRT I get and blow them out with compressed air. These JVCs get real nasty especially around the anode cup. The silicon grease they use turns black and gets filled with dirt. I always wipe that off the tube and anode cup.
 
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Tempest

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It is relatively safe to be working on a crt and take the board out as long as you discharge the monitor. Also be mindful of the psu capacitors. I open ever CRT I get and blow them out with compressed air. These JVCs get real nasty especially around the anode cup. The silicon grease they use turns black and gets filled with dirt. I always wipe that off the tube and anode cup.
You're braver than I am. Even knowing how to discharge a CRT (never actually did it though) I'd be nervous touching anything near the anode cup.
 

ChuChu Flamingo

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Contrary to belief the part that actually shocks you isn't that rubber anode cup, but the tube itself iirc. Not saying you don't need to be mindful of the flyback cable as it is directly connected to it.

Even more so on old monitors where High Voltage+time+heat have compromised the rubber insulating shielding. Micro cracks can form on there potentially setting yourself up to get shocked if you touch it without discharging. Very bad if you touch it while its on since you'll become ground.

https://en.wikipedia.org/wiki/Dielectric_absorption

The above phenomenon is why you can still get a shock if you don't discharge the tube multiple times. You'll often here of people saying their tubes recharged and they got a minor shock. Usually discharging one time is sufficient but I've seen a few tubes build up a charge again. In any case a lot of mid 90's crts and above auto discharge anyway via a bleed in resistor but only fools rely on that.
 
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GohanX

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I got bit by a monitor once. I couldn't tell you exactly what I hit, I don't remember clearly on account of being electrocuted at the time. I was young and dumb.
 

Tempest

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I got bit by a monitor once. I couldn't tell you exactly what I hit, I don't remember clearly on account of being electrocuted at the time. I was young and dumb.

I had a friend who was blindly reaching behind an arcade monitor in order to fix something while it was on and had it arc on his wedding ring. He was ok in the end but he never touched a live monitor again. I've done similarly stupid things like adjust a Compact Mac monitor while it was on to straighten it, but I was really careful and wasn't wearing my ring. :)
 

GohanX

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I think I was 14 at the time and had no concept of the fact that what I was doing was dangerous. I mostly just remember that I couldn't walk straight for a few hours, the shock messed up my motor control. Funny thing is I gave the tv to a friend who got a local shop to fix it for $30. Jerk.
 

Dochartaigh

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You think it could be the caps? The TV is from 2006, that seems a little early for caps to start failing. If it's the magnets or strips on the sides there's no way I'm fiddling with that as you can really do some damage if you don't know what you're doing. I think some of the blurriness on the sides is just due to the tube, these slimfit models are notorious for crappy convergence on the sides of the image. Then again, unless there's tiny text there you really don't notice it.

So which systems display a little to the right or underscan more than others (assuming we're using the SNES as the base system)? I have just about every system from the NES on up hooked up via RGB so I'm curious as to how I should adjust things to get the best positioning in general for all systems. The Neo Geo is a lost cause because the sides are so wide, unless I want to severely underscan all the other systems. Since you also have many different systems hooked up to your TV, can you share your thoughts on the positioning/sizing and or any thing else I should know?


enfXKKI.jpg


See on the right side how there's little red bumps where the horizontal red bar ends? Then see on the left side how there's a small indentation there in the same areas? That's usually caused by caps, usually in the deflection area (only fixed one like this, so my experience is limited - could very well be an easier tweak maybe a pro can chime in about). It might go away as it warms up, but will usually always return. 2006 isn't too early for caps to go bad, especially if they used cheap ones, or if the TV was left on 24/7 for the last decade+, or if the room it was in was usually pretty hot, etc. etc. etc.

For the sizing of the monitor for multiple systems, best I can give you is that screenshot I posted last time, and to have the 240p test suite available for as many systems as possible (and having a switch to quickly flip back and forth from multiple consoles really helps too - use my touchscreen Extron Crosspoint to do this). You'll NEVER, EVER get it perfect for all consoles FYI.




What causes this problem? From reading up replacing caps in the deflection circuit/power supply would fix this. This is a 32 inch JVC. My Commodore 1702 does this as well. I plan to recap that anyhow. It does it on the left side as well.

Funny how you posted that - I think it's a similar problem to the above, just a little worse. Yours is actually closer to how mine looked before I fixed it.

Also wanted to add that bad sync itself (and the monitor being just fine) can also do funky things like that, although I'm sure you've ruled that out (and it's usually near the top only).
 
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Tempest

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You'll NEVER, EVER get it perfect for all consoles FYI.
Yeah I've learned that over the years. I guess I should try and find something that works for everything even if I have to sacrifice some screen real estate to do so. Is there a list of console resolutions somewhere? From my experience the SNES seems to have the largest overscan area and the Genesis seems to have the smallest (barring the Neo Geo and it's weird horizontal resolution). So if I size the grid for SNES everything else should fit and not be chopped off (other than the Neo). I can try your shift right trick too.

I should let the TV warm up a bit and see if those go away. It was only on for a few minutes when I took those pictures. If not, well it's not too bad and we tend to forget that all CRTs back in the day usually had some sort of issue or another and we just dealt with it. Heck I can remember not being able to see the top inch or so of the screen when playing my Atari 400 until the TV warmed up. Suddenly it was like "Oh there's my score". :)
 

Dochartaigh

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Yeah I've learned that over the years. I guess I should try and find something that works for everything even if I have to sacrifice some screen real estate to do so. Is there a list of console resolutions somewhere? From my experience the SNES seems to have the largest overscan area and the Genesis seems to have the smallest (barring the Neo Geo and it's weird horizontal resolution). So if I size the grid for SNES everything else should fit and not be chopped off (other than the Neo). I can try your shift right trick too.

I just googled each and searched through the wikis. From my not super accurate spreadsheet I have: NES/SNES 256x224p, Genesis 320x240p mostly, Saturn 224p-ish, PS1/N64 seems to have both 224 and 240p. 5th gen (even PS2) seems to have a larger mix, launch screens and some FMV's can be 480i (even some game menus/maps), then the rest will be around 224/240p. The FirebrandX FM/OSSC profiles are good to take a look at too - he'll commonly make two profiles for a certain system to hit the majority of games (Genesis is a good example of this). Really confusing TBH. Like I said, I just kinda eyeball it with a bunch of 240p suite test grids, then eyeball again for the consoles I don't have the test suite for. No real science, and a lot of 'good enough' educated guesswork.
 

ChuChu Flamingo

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Like if you look up close to a 240p picture it has this weird pulsing. Kinda like a ~ is going through it. The severity of it ranges depending upon the tv (not all have it). S-video, component, doesn't matter. It is kinda like OSD flicker.

The worst one I have a 2005 JVC tv that has like 2500 hours. The model is a 27A45 and it actually keeps track of the hours its been on. Barely used imo and is in mint condition cosmetically. You can see it from a mile away. My Nanao MS9 has it ever so slightly but I honestly don't even notice it. That thing could definitely use a recap given how many hours its been on.

Im pretty sure something is out of spec, likely a capacitor. Just curious what can specifically cause this cause recapping a whole board you don't really learn anything.
 
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Dochartaigh

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Like if you look up close to a 240p picture it has this weird pulsing. Kinda like a ~ is going through it. The severity of it ranges depending upon the tv (not all have it). S-video, component, doesn't matter. It is kinda like OSD flicker.

~~~~~

Im pretty sure something is out of spec, likely a capacitor. Just curious what can specifically cause this cause recapping a whole board you don't really learn anything.

I know exactly what you mean with that flicker (have a video somewhere even). If my memory serves BVM-20F1U's have this problem on occasion, again, recapping the deflection board seems to be the solution. Sadly, I'm not at the technical level to know exactly which ones I just do them all the couple times I've did it (and it's a bitch without a ~$200+ solder sucker let me tell you...). Did the power boards twice as well just in case.
 

NEgO MANIAC

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Well, I got inside and the flyback didn't have any adjustment knobs. Is that normal for these? I guess I'll have to live with the lines.

Finally received my RGB cables and it looks great on the PVM. The only complaint that I have are light blue horizontal lines on the screen. They are only visible during dark color images. Plus my brightness adjustment isn’t very reactive. My guess is to adjust the flyback or possibly a cap kit. Any thoughts?
 

GohanX

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I used to have a 27" tv that I think used the same tubes as those lines of Magnavoxes. The svideo on it was amazing, even my newer "better" tvs didn't do svideo as well.
 
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