Fudoh's ode to old display technology

[Jademalo]

It's the one from retrogamingcables.co.uk for mega drive 2.
I'm not entirely sure what to do about this, because I'm not even sure where the issue is coming from, or if it's even an issue. I can only describe it as the lines not being entirely stable, the image seems to be synced fairly well.

I don't think that's normal. I tried three consoles (snes, ps and sat) with scart cables and none of them had this problem (the image is completely solid and stable). It might be worth contacting retrogamingcables to let them know of this issue. By the way I notice there's a setting that asks for region in the setup menu, did you put pal (if you're using a pal system)?

Oh no, I didn't find that one. Where exactly was it?
I know that I don't have a 21D, 24N or 25P, so that option might not be applicable. It's really strange though, it's extremely subtle but it's just not entirely steady. I'm struggling to google for advice too since it's difficult to describe.

[Taiyaki]

Oh no, I didn't find that one. Where exactly was it?
I know that I don't have a 21D, 24N or 25P, so that option might not be applicable. It's really strange though, it's extremely subtle but it's just not entirely steady. I'm struggling to google for advice too since it's difficult to describe.

Sorry I can't find it anymore. I remember for sure that it is there because I remember choosing NTSC 7.5 or something and in the selection there was PAL. Once I chose that and RGB from the selection (originally said YUV and I selected that and chose component and then RGB and it made the image perfect). I would continue looking but it's so late here I'll have to search again tomorrow. I hope you get this solved.

[Jademalo]

Oh no, I didn't find that one. Where exactly was it?
I know that I don't have a 21D, 24N or 25P, so that option might not be applicable. It's really strange though, it's extremely subtle but it's just not entirely steady. I'm struggling to google for advice too since it's difficult to describe.

Sorry I can't find it anymore. I remember for sure that it is there because I remember choosing NTSC 7.5 or something and in the selection there was PAL. Once I chose that and RGB from the selection (originally said YUV and I selected that and chose component and then RGB and it made the image perfect). I would continue looking but it's so late here I'll have to search again tomorrow. I hope you get this solved.

Yeah, that's input select. I only have YUV and RGB since I don't have an NTSC/PAL decoder board.
The more I'm trying to fix this though, the more I'm wondering if it's a trick of the eye. I'm extremely confused, lol.

EDIT: After a bit more testing today, it definitely seems to lessen when the Monitor warms up a bit. Which begs the question, does anyone else get it when powering the monitor on from cold?

[Taiyaki]

You're right the PAL option seems to be for the Composite setting.

I'll receive my scart for Genesis shortly so I'll let you know if I have a similar shimmering.

Spent tons of time trying to deal with geometry. Convergence settings are plentiful and that's great. But geometry seems to be lacking. I can't get a good calibration with just H pin and H key. I thought there's a V pin normally too.

[Jademalo]

Sweet, thanks. It definitely seems to be at it's worst on a cold start, if you load up something like Sonic 2 then it's incredibly apparent along the blue lines at the top.

Has anyone got a solid guide to the convergence settings on this thing? I'm fairly close I think, but I'm not entirely sure regarding every setting. I have a feeling that if I understood them a bit better I might be able to lessen this shimmering.

[Fudoh]

Has anyone got a solid guide to the convergence settings on this thing?

convergence might take a little time, but it's easy. Just call up a grid pattern and adjust every single item in the menu. You'll immediately see which area of the screen is affected and just set each of them in a way that no colored seams are visible next to the white grid lines.

[Jademalo]

convergence might take a little time, but it's easy. Just call up a grid pattern and adjust every single item in the menu. You'll immediately see which area of the screen is affected and just set each of them in a way that no colored seams are visible next to the white grid lines.

Alright, cool. Are there any 240p test patterns or are they all interlaced? My eyes get tired if I'm close to it when it's interlacing.

[Fudoh]

The test patterns are all interlaced. Artemio's 240p test suite for DC, MD und MCD does include 240p patterns.

[Jademalo]

Oh sweet, thanks for telling me about that. I'm planning on picking up a mega everdrive fairly soon, so that should be highly useful.

[Taiyaki]

Does the Mega Everdrive also have the test suite?

EDIT:

Thanks to Fudoh's advice of calling up Pro Sony support center I was able to get the code necessary to enter the service menu of the BVM20-G1U. This might work for other BVM's that don't have full geometry options in the "alignment" menu.

To access go to Maintenance and put in code 53415 (it will only show 4 stars but actually will work). In the third option there you can find all the missing geometry settings that are found on the F line and probably some other BVM's.

[Jademalo]

I got lucky and managed to guess the passwords to my 20F1E, 9999 and 1111 =p

[Taiyaki]

You're right mine worked with 1111 too (not 9999 though).

My geometry isn't going so well. I have the part between center and bottom that is streched outwards and have no idea how to fix it (pin seems to affect from center on so it only carries on the problem). Spent 4 hours at least so far on geometry and I'm wondering at times if I haven't made it worse. lol

Unlike the F model I have no center pin and corner pin, instead I have U cor pin (upper part) and L cor pin (lower part) and a H bow and H center bow settings.

[Jademalo]

You're right mine worked with 1111 too (not 9999 though).

I found two password things, one was maintenence mode and one was the password section in set up. The set up one was 9999, the maintenence was 1111. Thank god the person who had this monitor before me didn't change them, it would have been an absolute nightmare and a half to try and find those out.

[Taiyaki]

Have you managed to get good geometry?

EDIT:
Geometry settings are lacking in Vertical options, I find the vertical bars aren't straight and are curved on the edges and the bottom which is what is giving me that mirror warped effect picture in 2d scrolling games. I've spent at least 5 hours today, pretty much all my free time on it and could not achieve good geometry. Real bummer.

[Jademalo]

Mine is so-so, haven't had a real attempt at it yet since I've been both busy and buying lots of nice equiptment =p

[Taiyaki]

Turns out I'm wrong, Fudoh corrected me, vertical options aren't there because the display's horizontal lines are fixed and can't be changed, so apparently it's all about the vertical lines. I had to stop trying earlier because the warping during in game testing was giving me a headache. Will try again later.

By the way did you ever figure out the problem with the Megadrive Scart cable? Do you run it on a modded MD?

[Traveller]

Just got home with my Sony PVM-20M4A, looks great. It was apparently only used in an OB truck, so hasn't been run constantly for years and years. At the moment I have a PAL N64 plugged in through S-Video.

Only thing is I want to centre the image slightly, it seems that it is pushed slightly to the right. There might be other adjustments I should do, but it seems good already. I don't have any external test pattern generator or anything and am pretty new to adjusting these monitors, any advice is appreciated.

[Mad Grab]

Looking at BVM's, what is considered average to low operation time for the age of these CRT's.
Around 50000h? Or should I look for something lower.

***********EDIT**************

OK read the first 28 pages....wow!
Will finish the rest later. Looks like 50000h is average:)

[Jademalo]

Good god, someone please save me from 20F1E calibration.

I have absolutely no idea how to do this.
I've got convergence pretty close, except for the bottom left corner vertically. Since there are only 3 vert options I've got no idea how to fix that, but the rest of it is pretty solid.

My big issue though is geometry. I can get three corners perfect, and one is out. Every. Single. Time. But then, I don't even know what I'm looking for. The top line hugs the top, but the bottom line is more real-world straight but compared to the bezel is curved. I don't even have a clue what linearity does except for mess everything up, let alone linearity balance. H Pin balance doesn't seem to do anything either.

Does anyone have sort of a.. guide of what to look for to actually calibrate it to a solid image? Six hours of staring at an interlaced grid have given me a headache, and I've literally got no idea what I'm doing. Some options affect the image in really bizzare ways, and I've got no idea what they should actually be aiming towards and what should be compensated with what. How exactly do you guys go about calibrating one of these?
Below is a list of the ones that are totally confusing me as to their purpose.

H PIN BAL - Seemingly does nothing.
H CENTER PIN - Weirdly skews the bottom of the image
H MID PIN - Absolutely no idea
H KEY BAL - Sort of twists it a bit? I don't know.
H LIN - No idea
H LIN BAL - No idea


I'm literally losing my mind, it was six hours and I swear I'm right back where I started. My biggest issue is that one corner will be "out" and then norhing works. I can have one side dead straight down and the other one is straight until the middle then violently curves off into space. Trying to correct it always throws something else out just slightly. If I knew what I was actually looking for and what was classed as "correct," I could probably get something close then tweak it to perfect. My problem is that I don't even know if it's close.

Another problem I'm having is a sort of... bulge(?) on the right hand side of the screen when something is scrolling. Nothing I seem to do affects it, but it's like it's compensating badly for glass or something. I'm assuming this is something that can be corrected, but I have absolutely zero idea of where to begin.

[Taiyaki]

You seem to be having the same difficulty I have.

H Lin changes the distance between the lines left and right of the picture, so this is useful if things are too wide in the center or too wide on both sides. H lin bal changes the balance from left to right but be careful because it also moves the center I believe.

I don't think I have H pin Bal on my 20G1U so I'm not sure. H Mid pin warps the middle I believe. It's a useful one that might be required to solve the corner problem you have.

I have a problem on the left side and not the right of bulging (maybe we have a similar problem?) in my case it's the extreme left everyone is extra wide and then the picture looses in width before going back to normal close to the center, everything on the right is perfect. Nothing affects that issue. Result is if the moon scrolls through the screen it goes oval for a bit before going fat and leaving the screen. I made a thread about that but haven't taken video yet to show the problem. No one was able to advise on how to fix this.

[Fudoh]

If I find the time, I could try to do a little "how to get geometry & convergence right" tutorial sometime.

[Jademalo]

If I find the time, I could try to do a little "how to get geometry & convergence right" tutorial sometime.

Oh man, I would seriously appreciate something like that right now.
I spent another couple of hours on it, after getting the 240p test suite to work through my wii I got linearity seemingly better, but I still have the "bump" on the left hand side of the image, as if it's rolling over a finger or something about a fifth of the way in. I'm a little concerned because I have absolutely no idea what I should be trying to do to sort it. Even then though, I don't know when I should be modifying very linearity to pull the circle up, or h linearity to squash the sides in to get it circular. A guide from someone who knows what they're doing would be massively appreciated.

I have a problem on the left side and not the right of bulging (maybe we have a similar problem?) in my case it's the extreme left everyone is extra wide and then the picture looses in width before going back to normal close to the center, everything on the right is perfect. Nothing affects that issue. Result is if the moon scrolls through the screen it goes oval for a bit before going fat and leaving the screen. I made a thread about that but haven't taken video yet to show the problem. No one was able to advise on how to fix this.

That's kind of similar to what I have! Except mine is a lot more subtle. It's only really noticable for me on certain scrolling things, the most apparent was ALttP when I was in Kakariko. The very left edge is fine, but then as it goes in it goes over a little bump for about 10% of the screen, then past that everything is fine.
What's strange is that it doesn't show itsself on grids.


On another note, I seem to have messed up the image size on the underscan/normal 4:3 presets, and I'm not sure how to get it back to normal. I thought it was maybe to extend it so the red squares aren't visible on the test suite, but vertically there isn't enough extension. I have absolutely no idea now what the proportions between the two should be.

[Taiyaki]

The issue on my end covers about 25-30% of the screen and I know what you mean that it feels like a bump. It's because the width is messed up. Also I agree it's very hard to see with a grid. The best way to see it is to look at those color patterns which have wider and more defined lines since they change color, that's where it's clearest as you'll see one of the color bars being smaller or bigger.

A calibration guide from Fudoh would surely be most useful to most of us with little experience calibrating.

[BubbaMc]

Turns out I'm wrong, Fudoh corrected me, vertical options aren't there because the display's horizontal lines are fixed and can't be changed

I'm having the same issue, the horizontal lines towards the bottom of the screen aren't perfectly straight. It's bugging me a bit. Just wondering if there's anything that could be done about this, possibly placing magnets on the back of the tube? Fudoh?

[Taiyaki]

I'm starting to wonder if the problem might not be internal, maybe some capacitors or some other problem on the board.

[jedman]

I'm interested in getting a sony BVM-20F1,

I've read a lot of this thread and other details but i'm still not sure what the differences are between the BVM-A20 and the D20 are.

And am I right in thinking that the D and A will accept a 15khz 240p signal right up to 30khz 720p?

So I could use this monitor from SNES up to PS2?

I've come across a BVM-A20 and a D20 but they are the same price, although it looks like the A doesn't have the analog input BKM-68X and I cant find anywhere to get this that doesn't cost more than the monitor itself.

Also they come with no power supply or control unit, but I've found the control unit available elswhere.

Could someone advise me on what exactly I need and what the best option would be to go for.

Many thanks

[Fudoh]

BVM-20E/F/G = 15khz only
BVM-D and BVM-A = multisync for 15khz (240p/480i), 31khz (480p), 47khz (720p and 1080i)

As you noticed yourself, the D units come with an analogue input board by default, while the A doesn't.

[jedman]

Ok cool

are there any advantages to the BVM-A other than being newer so I guess potentially less used unit?

Do you know where I could get the analogue input board from for cheap? only one I could find was this which is a lot more than the monitor itself.

http://www.proav.co.uk/Sony-BKM-68X-Inp ... 17138.aspx

Also what power supply do I need for the BVM? the ones ive seen don't come with one.

Thanks

[Fudoh]

I would just go with "D" unit instead. You don't need a power supply, just a standard 3-prong power cable.

[Traveller]

I was playing around more with my PVM this morning, I have adjusted it to fix the output for a PAL N64, it all seems pretty good.

Just a question though. Can someone explain simply how I should set the H-Frequency and Video Phase options? At the moment I have used both to center the picture. Does the frequency not matter too much as long as the image appears stable?

Thanks.

H-Freq - 128
Video Phase - 85 (I think around there)