Would this Sony television be suitable for a universal chassis?

[konp]

So I've got a beast of a CRT sitting unused in my back room, it still works (apart from a bit of 15khz whine from the flyback) and the picture is very nice. However, it only has Composite and S-Video input. I've been entertaining the idea of throwing it in a cabinet and using it for the "authentic CRT experience" (both of my existing cabs were built around LCDs), but I only want to do that if I'm going to be able to feed it a proper RGB signal.

However, it's a Sony Trinitron flat from the late 90s/early 2000s. I've seen a few things around saying that many of these are unsuitable for use with universal harnesses because Sony got creative with the yoke wiring (6 wires instead of 4?), among other things. But I can't find anything definitive on this model, partially because according to the internet it doesn't exist (more on that later) and partially because what I CAN find is only very vague and non-committal.

So I figured I'd decase the sucker and take a few photos of (as far as I can tell) the yoke wiring.



Here's the harness coming out of the board. It has space for 6 pins, but only 4 of them are occupied - 2 thick, 2 thin. This appears to follow the standard setup for yoke wiring. However, the board labels are... weird. Apparently, from left to right, the wires are "H+ H+ H- V+". Now obviously that can't be right.



Here's a closeup of the wires. As you can see, colour wise they appear to follow a standard as well.



Here's where 3 of the 4 wires end up. This is on the left-hand-side of the TV.



Wire 2 goes here.



Model details.

Now, on to it not existing. The internet stubbornly refused to produce any manuals for the version I have. However, I could easily find them for the KV-XF25M50 and KV-XF25M80 which appear to be basically identical, and they both use the BG-3S chassis, which is the same chassis mine uses (found a picture of the front page of the service manual for mine that corroborated this). Reading through the manual for the M50/M80 (got them from elektrotanya if you wanted to have a look) has only given me a limited amount of insight, because the schematics may as well be Greek to me. I can visually match components, that isn't hard, but the rest of it is gobbledygook.

Obviously this is all moot if the yoke wires don't fall within the correct ohm ranges for the universal chassis, but let's just assume that they will if they're the setup I'm looking for.

-edit-

I just went and compared the neck connector on the C-board to the one on the Weiya universal chassis, and it looks pretty much the same. So that's a plus.

-edit 2-

Figured I'd check the ohms of the vert/hori while I had it open. I got 10 for vert and 2.2 for hori. So smack in the middle of where it needs to be. Oddly enough, the thin cables (1 and 2) have 2 sockets at their ends, not one. So there are 6 pins connected on the A-board. However, there's only 4 wires coming out of the yoke.

Really seems like I should be fine to use a universal chassis with it. Hope that's the case and I'm not counting my chickens.

[lilshawn]

you need to properly measure the yoke INDUCTANCE to properly match a universal chassis to a tube/yoke.

You will need to beg/borrow/steal/buy an LCR meter and give the horizontal/vertical measurements to someone like nieman displays and have them match a chassis to the set you have. the yoke is measured in "henries" and being off by a few millihenries can cause the screen to be distorted to the point where no amount of adjustment tweaking can fix it, or worse blows up as soon as you power it up.

if you call anybody respectable up requesting a universal chassis with ohm measurements they will absolutely tell you the to get an inductance meter and come back with a reading. Anybody who will sell you a chassis based on ohm readings from the yoke is out to make money off you, not get you the proper chassis.

an LCR meter can be purchased off ebay for about 40 or 50 bucks. If you would never ever use it again, perhaps call some repair places and ask if they have one you could borrow for an hour while you measure it.

[konp]

you need to properly measure the yoke INDUCTANCE to properly match a universal chassis to a tube/yoke.

You will need to beg/borrow/steal/buy an LCR meter and give the horizontal/vertical measurements to someone like nieman displays and have them match a chassis to the set you have. the yoke is measured in "henries" and being off by a few millihenries can cause the screen to be distorted to the point where no amount of adjustment tweaking can fix it, or worse blows up as soon as you power it up.

if you call anybody respectable up requesting a universal chassis with ohm measurements they will absolutely tell you the to get an inductance meter and come back with a reading. Anybody who will sell you a chassis based on ohm readings from the yoke is out to make money off you, not get you the proper chassis.

an LCR meter can be purchased off ebay for about 40 or 50 bucks. If you would never ever use it again, perhaps call some repair places and ask if they have one you could borrow for an hour while you measure it.

Ok so how come no universal chassis I've looked at mentions anything other than making sure the ohms of the yoke wiring are between 6 and 12 for vertical and 1.5 or above for horizontal? The only one that seems to be available these days is the Wei-ya one anyway.

[pbj]

Probably a lot easier to just buy the chassis and cross your fingers than it is to drive all over the damn place trying to borrow a tool.

[konp]

Probably a lot easier to just buy the chassis and cross your fingers than it is to drive all over the damn place trying to borrow a tool.

Actually from the looks of things, the incompatibility might lie with the neck connector itself. It's got 11 pins. Seems the standards are 8, 10 and 12. 11 is sony being creative again, apparently. GG, sony.

So I guess my next question is a) Is there such a thing as a VGA-to-Svideo transcoder at 15khz that will give me the best picture I can get on that input, or b) is it a relatively easy task to hack in an RGB input myself somehow (considering that the TV has to be driven by an RGB signal to the electron guns at some point, theoretically I should be able to just splice in an input at that point).

[lilshawn]

Ok so how come no universal chassis I've looked at mentions anything other than making sure the ohms of the yoke wiring are between 6 and 12 for vertical and 1.5 or above for horizontal? The only one that seems to be available these days is the Wei-ya one anyway.

Because they don't give 2 shits if you plug it on there and it blows up. they got their 100 bucks out of you.

Reading the resistance will get you a chassis that will get you to the right city. Reading the inductance will get you to the ballpark. Tweaking the pots will get you from the parking lot to the home plate. Tweaking pots ain't going to do a lot of good if you are not even in the right city

you will have to have a look at the neck board and see if it's a standard pinout or not. It may be a standard 12 pinout and could just have the heater tied to ground instead of 2 dedicated pins for in and out.

any kind of convertor is going to introduce lag to the picture. apparently it's a problem for some people. Be aware of it.

what are you hooking up to this thing? if you are just running mame, maybe try and find yourself a videocard that has COMPONENT YPbPr aka: "HD" output (if you can find a tv that supports it) there are still tons of tv's out there. you would be much happier with the image of a higher res signal. depending on your application, perhaps a VGA monitor would be best. not only would you benefit from a ready made solution, but your monitor will automatically sync to any resolution you throw at it.

video hierarchy worst to best

coax<composite<s-video<component<DVI/HDMI<VGA

[konp]

Ok so how come no universal chassis I've looked at mentions anything other than making sure the ohms of the yoke wiring are between 6 and 12 for vertical and 1.5 or above for horizontal? The only one that seems to be available these days is the Wei-ya one anyway.

Because they don't give 2 shits if you plug it on there and it blows up. they got their 100 bucks out of you.

Reading the resistance will get you a chassis that will get you to the right city. Reading the inductance will get you to the ballpark. Tweaking the pots will get you from the parking lot to the home plate. Tweaking pots ain't going to do a lot of good if you are not even in the right city

you will have to have a look at the neck board and see if it's a standard pinout or not. It may be a standard 12 pinout and could just have the heater tied to ground instead of 2 dedicated pins for in and out.

any kind of convertor is going to introduce lag to the picture. apparently it's a problem for some people. Be aware of it.

what are you hooking up to this thing? if you are just running mame, maybe try and find yourself a videocard that has COMPONENT YPbPr aka: "HD" output (if you can find a tv that supports it) there are still tons of tv's out there. you would be much happier with the image of a higher res signal. depending on your application, perhaps a VGA monitor would be best. not only would you benefit from a ready made solution, but your monitor will automatically sync to any resolution you throw at it.

video hierarchy worst to best

coax<composite<s-video<component<DVI/HDMI<VGA

I had a look at the backside of the C-board (with the neck connector) and I count 10 solder points. It has 11 pins, 10 solder points. WTF. I triple-counted to be sure - 10. I'm guessing 2 pins are tied to one input then.

The reason I want to use this screen is because it works well (apart from the flyback being a little noisy - my gf can't hear it but to me it's nails on a chalkboard), the quality of the picture is quite good for a composite/s-video only set, it's 25" so nice and big (I like big TVs...) and it's gathering dust at the moment and I'd rather put it to good use, considering I probably couldn't even give it away.

As for "what", it really depends on what my options are. If it turns out to be compliant with a universal chassis, I'll go that route and ditch the current internals, and build a MAME cabinet around it. If it turns out to be locked to Sony hardware (which admittedly wouldn't surprise me at all, I know what Sony are like with their proprietary ---That which is odiferous and causeth plants to grow---) then I'll go a VGA-to-Svideo transcoder and probably build it... into a MAME cabinet. Or maybe a Stepmania machine, I'd like to have one of those.

And yeah I know about the video heirarchy thing. I got the set when component was only just becoming "a thing" here in Australia, so it only had Svideo. At that point people were still totally happy with composite. Interesting that you rank VGA above DVI/HDMI, why is that? Theoretically would it be better to drive an LCD TV from a computer with the VGA port or the HDMI port? I ask because I have both options on my cabs and would like to hear what you think.

[lilshawn]

although VGA is analog, it's resolutions can go higher than the standard HDMI compliant specs (without going into to 4K.) It's not uncommon for VGA to be 1920x1200 , 3200x1800 or higher... it's really only limited by the construction/quality of the cable and capabilities of the connected monitor.

[konp]

although VGA is analog, it's resolutions can go higher than the standard HDMI compliant specs (without going into to 4K.) It's not uncommon for VGA to be 1920x1200 , 3200x1800 or higher... it's really only limited by the construction/quality of the cable and capabilities of the connected monitor.

I seeeee.

Well, since both of my screen have a max res of 1080p, HDMI is still probably a better choice for me.

[lilshawn]

exactly, there is no sense trying to feed a signal it doesn't natively support. All you end up doing is doubling some pixels and having unevenly grainy pictures or on the flip side wit a smaller resolution... halving pixels and losing information.

try feeding your LCD some mame, i have a feeling you'd be surprised at how it looks...with some creative bezel work, a big 30" flatscreen can look pretty damn good.

if you are really partial to CRT... There are some video convertor options out there, but it could be expensive... there could be something half decent that can hook up to your monitor and still look okay, and NOT break your budget. (connect to s-video etc.)

[konp]

exactly, there is no sense trying to feed a signal it doesn't natively support. All you end up doing is doubling some pixels and having unevenly grainy pictures or on the flip side wit a smaller resolution... halving pixels and losing information.

try feeding your LCD some mame, i have a feeling you'd be surprised at how it looks...with some creative bezel work, a big 30" flatscreen can look pretty damn good.

if you are really partial to CRT... There are some video convertor options out there, but it could be expensive... there could be something half decent that can hook up to your monitor and still look okay, and NOT break your budget. (connect to s-video etc.)

Oh I've already got two cabinets with LCDs in them, once's a 24" 16:10 LG monitor and the other is a 32" Sony LCD television (this one is still in-progress, I'm building it as a semi-dedicated cab for the newest mortal kombat game). And you're right, with the correct settings they look great. I have them set up for HLSL scanlines and I'm very happy with the result.

The reason I'm wanting to get use out of the CRT is because it still works, and does so very well. Sure, it's a little dusty, it's aging technology, and it's got that 15khz flyback whine that seems ubiquitous with CRTs, but it was a damn good TV when it was current tech, and it would look good as an arcade display. I figure it's not going to cost me any extra to use it (as in, I don't have to buy a new screen) and it'd be nice to have one cabinet with a CRT in it, because I grew up with CRT cabs and it would be very nostalgic.

[lilshawn]

grab yourself one of these off ebay... http://elongshine.com/27

it's a VGA to s-video/composite converter. you may have satisfactory results. I bought one to hook my laptop to the DVD screen in the van for the kids to watch videos. i think i paid $1.12 plus $12 shipping or something ridiculous like that. don't get suckered into buying this... http://dx.com/p/vga-to-s-video-and-3rca-f-cable-9813#.UusW4z1dXh4 there is no possible way it would work unless you videocard specifically supported this mode of operation.

[konp]

grab yourself one of these off ebay... http://elongshine.com/27

it's a VGA to s-video/composite converter. you may have satisfactory results. I bought one to hook my laptop to the DVD screen in the van for the kids to watch videos. i think i paid $1.12 plus $12 shipping or something ridiculous like that. don't get suckered into buying this... http://dx.com/p/vga-to-s-video-and-3rca-f-cable-9813#.UusW4z1dXh4 there is no possible way it would work unless you videocard specifically supported this mode of operation.

Was actually looking at something like this. I've seen it recommended in a few places. It has an Svideo out and does the transcoding itself so that the TV doesn't have to do any additional processing.

[lilshawn]

that is more or less the same thing i posted, but without a plastic box.

[vandale]

grab yourself one of these off ebay... http://elongshine.com/27

it's a VGA to s-video/composite converter. you may have satisfactory results. I bought one to hook my laptop to the DVD screen in the van for the kids to watch videos. i think i paid $1.12 plus $12 shipping or something ridiculous like that. don't get suckered into buying this... http://dx.com/p/vga-to-s-video-and-3rca-f-cable-9813#.UusW4z1dXh4 there is no possible way it would work unless you videocard specifically supported this mode of operation.

Was actually looking at something like this. I've seen it recommended in a few places. It has an Svideo out and does the transcoding itself so that the TV doesn't have to do any additional processing.

cheaper and probably arrive faster from here:
http://www.arcadespareparts.com/arcade_parts/video_converter/vga_rgb_cga_video_converter/12215.html

they arrive in New Zealand in 2 days on standard shipping so probably the same in the states

[konp]

grab yourself one of these off ebay... http://elongshine.com/27

it's a VGA to s-video/composite converter. you may have satisfactory results. I bought one to hook my laptop to the DVD screen in the van for the kids to watch videos. i think i paid $1.12 plus $12 shipping or something ridiculous like that. don't get suckered into buying this... http://dx.com/p/vga-to-s-video-and-3rca-f-cable-9813#.UusW4z1dXh4 there is no possible way it would work unless you videocard specifically supported this mode of operation.

Was actually looking at something like this. I've seen it recommended in a few places. It has an Svideo out and does the transcoding itself so that the TV doesn't have to do any additional processing.

cheaper and probably arrive faster from here:
http://www.arcadespareparts.com/arcade_parts/video_converter/vga_rgb_cga_video_converter/12215.html

they arrive in New Zealand in 2 days on standard shipping so probably the same in the states

I'm in Australia so it'd probably take around the same amount of time. Maybe a day or two more because Aus Post sucks.

What would be involved in engineering in an RGB input to this television? I mean, I can locate the RGB out (that feeds the tube guns) on the schematics, and I'm not an idiot, so surely it'd be possible to hack in an RGB feed to the TV.

I know plenty of you have done it, but I understand that it's a little different each time depending on what TV you use. So provided I could locate the necessary outputs to splice into, and the necessary voltage level for the signals, surely it wouldn't be too complicated?