99 problems and all relate to CRT use.

[relo]

I'm currently trying to design my first MAME arcade, but I've ran into some issues with using a CRT (in my case a Sony trinitron KV-25R2D).

1. I've read that you could damage using an 31Khz input on a TV, and using soft 15K to display it proper. But before booting that software (automatically) how can I protect my TV or shouldn't I worry about it?
2. I'm looking into making it a rotating screen (as I like shooters), is there a tested and well documented way to rotate a CRT?
3. If I can rotate it, would I degauss it after rotation?
4. If I can rotate it, how much extra room would I need to do that?
5. Apart from vertical shooters is there anything else worth a rotating screen for?
6. I've read having vertical/rotating CRT could be a fire hazard, how could I protect against that, if that is true?
7. Can vertical games look half decent on a CRT with just software rotating them, instead of a full monitor rotation?

I think that is all right now, Thanks in advance for the help.

[twistedsymphony]

I'm currently trying to design my first MAME arcade, but I've ran into some issues with using a CRT (in my case a Sony trinitron KV-25R2D).

Most of your problems stem from the fact that you're using a TV instead of an arcade monitor...

I consider myself president of the LCD haters club but seriously I would use an LCD over a CRT TV. I really hope this screen supports 240P over RGB scart otherwise it's only real benefit is for a tube swap on a real arcade monitor IMO.

Arcade monitors have a nice big metal frame with nice big mounting tabs that make them easy to mount and IMO are a necessity if you want to rotate the screen. Instead of a thick metal bracket you're working with a blob-like plastic shell that's not designed to be mounted never mind turned sideways.

1. I've read that you could damage using an 31Khz input on a TV, and using soft 15K to display it proper. But before booting that software (automatically) how can I protect my TV or shouldn't I worry about it?

yes you can damage it... the electronics can't handle a signal that far out of range and sometimes they cook themselves trying to interpret it.

you'll need something like a JPAC or the Ultimarc VGA adapter to block out of range refresh rates... otherwise you'll need to turn the screen and your PC on separately or rig up a custom solution such that your PC turns on your screen once the video is in range.

2. I'm looking into making it a rotating screen (as I like shooters), is there a tested and well documented way to rotate a CRT?

there are a number of screen rotating projects I don't think there is a "best method" a lot of it depends on the screen and your cab layout... I don't think I've ever seen one that uses a TV though, that's a huge extra bit of difficulty.

3. If I can rotate it, would I degauss it after rotation?

if you want... I wouldn't think it would be necessary every time though. Usually degausing needs to occur when the monitor is moved in relation to the magnetic poles of the earth... I could be wrong but I don't think rotating it vertically would effect it much.

4. If I can rotate it, how much extra room would I need to do that?

this depends on your mechanism but at absolute minimum the width and heigh of your monitor area would have to accommodate the largest diagonal dimension of your monitor... probably a few inches more to accommodate whatever you've designed to hold the monitor (this would be quite large trying to hold a plastic encased TV as opposed to a metal framed arcade monitor.

5. Apart from vertical shooters is there anything else worth a rotating screen for?

lots and lots of classic games use vertical monitors... Pac-Man, Donkey Kong, etc.

6. I've read having vertical/rotating CRT could be a fire hazard, how could I protect against that, if that is true?

I've never heard of this... as long as everything is secured properly I don't see why it would be anymore of a fire hazard than a non-rotating monitor.

7. Can vertical games look half decent on a CRT with just software rotating them, instead of a full monitor rotation?

at 15K resolution it would probably look really bad... you'd be cutting your already low resolution in half.... if you were running a 31K capable arcade monitor and didn't mind dealing with not using the whole screen it'd be fine.

[Yeltsew7]

I'm currently trying to design my first MAME arcade, but I've ran into some issues with using a CRT (in my case a Sony trinitron KV-25R2D).

Unless this had RGB SCART or Component YPbPr inputs, you're not going to get  anything worth using on it.

1. I've read that you could damage using an 31Khz input on a TV, and using soft 15K to display it proper. But before booting that software (automatically) how can I protect my TV or shouldn't I worry about it?

DO NOT USE SOFT15KHZ.  Use GroovyMame and CRT_Emudriver.  The only reason to use soft15k would be if you need to use an nvidia card or use Windows 7, and it is working for Windows 7 nicely I think.  Also, an ATi card is like $20, it's not much trouble, is it?

5. Apart from vertical shooters is there anything else worth a rotating screen for?

There's not much use in rotating a 25" screen, when you display vertical games on it with the black bars in the side, they are about 19", I think, which is what they ran on for the most part.

6. I've read having vertical/rotating CRT could be a fire hazard, how could I protect against that, if that is true?

See above.

7. Can vertical games look half decent on a CRT with just software rotating them, instead of a full monitor rotation?

Depends, with YPbPr they can look sort of nice, better than any LCD, but they would be at 480i to display the whole game squashed in the middle.

[relo]

I live in europe, so I have heavenly RGB SCART on every CRT and can do 480i, so software rotation is probably a better option. And GroovyMame and CRT_Emudriver is probably better.

Now I'll only need a way to protect my TV from 31k before that is booted, right?.

[Yeltsew7]

Oh, forgot to mention that.  Most modern TVs have some kind of protection, and as long as you don't leave it in 31khz for too long, it should be fine.

[rCadeGaming]

1. I've read that you could damage using an 31Khz input on a TV, and using soft 15K to display it proper. But before booting that software (automatically) how can I protect my TV or shouldn't I worry about it

+1 on Yeltsew's advice on GroovyMAME and CRT_Emudriver.

From my experience, TV's are more likely to be safe with out of range signals than arcade monitors.  The Trinitrons I've tested haven't had any problem with it, they'll display garbage on screen, but aren't damaged. 

This is by no means a guarantee that it will be safe on your TV though.  The safest thing to do is wait until Windows has booted and the output is 15kHz before turning the TV on.  I'm planning on using a PLC to turn mine on that is triggered once my front-end loads.  There are also simple computer-controlled relays available.  A really simple solution is to use separate speakers and wait for the Windows start-up sound before turning on the TV.

2. I'm looking into making it a rotating screen (as I like shooters), is there a tested and well documented way to rotate a CRT?

I've thought about a rotating CRT cabinet, but I'm concerned about the stability of the geometry.  Once a CRT is calibrated really nicely it's best not to move it.  Moving it in relation to the poles of the earth and other magnetic fields has an effect; I think that would include just rotating it.  You'd have to test whether it's noticeable with your TV. 

The bulk of a mechanism that can safely rotate such a heavy display is also a concern, as twistedsympony also mentioned.  This isn't to say it hasn't been done though.  Here's a well-executed example in progress:

http://forum.arcadecontrols.com/index.php/topic,131026.0.html

That's the first I can think of, but not the only one; search around.

3. If I can rotate it, would I degauss it after rotation?

Yeah, that'd be helpful.  If your set has an internal degaussing coil on the back of the tube, you might be able to wire up a switch to activate it on demand.

5. Apart from vertical shooters is there anything else worth a rotating screen for?

Are there other vertical games worth playing?  Yeah, lots.  All the classics from the early era like Yeltsew mentioned.  Contra also comes to mind.

6. I've read having vertical/rotating CRT could be a fire hazard, how could I protect against that, if that is true?

A fire hazard?  Never heard of that one 

7. Can vertical games look half decent on a CRT with just software rotating them, instead of a full monitor rotation?

Playing vertical games on a horizontal monitor is known as yoko orientation or yoko-tate in the shmup community.  There is a good deal of talk about it in this board.  You should check out the thread on TV's in my signature.  Long-story short, yes you have to scale it in 480i, so it's a compromise. 

When making the extra effort to use a real CRT you should always run your games in proper native resolution (~240p for 90% of MAME) whenever possible, or else you aren't getting nearly the full potential out of the display.  Of course this isn't always possible, so if you don't have a rotating cabinet or a seperate vertical cabinet yoko games are a typical area of compromise, along with 25 and 31kHz games, all of which are typically scaled to 480i on a 15kHz tube.

Most of your problems stem from the fact that you're using a TV instead of an arcade monitor...

I consider myself president of the LCD haters club but seriously I would use an LCD over a CRT TV. I really hope this screen supports 240P over RGB scart otherwise it's only real benefit is for a tube swap on a real arcade monitor IMO.

When properly set up, a 15kHz CRT TV can rival the picture quality of a 15kHZ CRT arcade monitor.  The only real difference is the input format.  OP, you just need to confirm that your SCART input accepts RGB, as SCART can also carry composite, s-video, etc.

For anyone else reading, note that non-SCART TV's can get the same performance by using a VGA to component transcoder, provided the TV is 15kHz ("standard definition") and has a component input.

Arcade monitors have a nice big metal frame with nice big mounting tabs that make them easy to mount and IMO are a necessity if you want to rotate the screen. Instead of a thick metal bracket you're working with a blob-like plastic shell that's not designed to be mounted never mind turned sideways.

Many TV tubes have the same mounting tabs/ears as arcade monitors, so they can be easily mounted to a frame after decasing.

[relo]

Well I've decided against rotating, I dont really notice the interlacing on the TV. So it seems more an hassle than that it's worth (now I know I don't notice it without pushing my eye 10 cm to the tube). Not to mention most of those games I'd likely play alone, so not much added value would be there from a rotating screen at least for me.


I think the fire hazard thing comes from in cased TV's (heat build up when it can't properly escape maybe?)

And it has RGB SCART in. (otherwise my 60hz consoles would be colorless on the 50hz TV)

And yes, the tube has mounting ears. At least the 4 around my house.

[apfelanni]

i have a trinitron 25x5d in my ok baby cabinet for vertical lowres shooters . the sonys are decent arcade replacement screens , easy to handle and not so picky with the inputs.  the 20 seconds off range frequency isnt much of a prob . some of my cabbed tvs handle it for years now without any casualties .

there are a lot of classic games playing vertical , but u wont like em on the sony , because the screen ist to big . for oldystyle games ud better check out for a 20-21 inch screen standard cabinet or a 17 inch for cocktails or lowboys .

i choosed the 25 inch sony for vertical and a 25 inch philips for hori , but i wish i had done it the other way round . the sony would better be in hor orientation and the philips is a little bit smaller , which would have enhanced the funfactor playing vertical shooters . another pro philips are less geometry issues when tated . most sonys dont like to be mounted tated .

u should also be aware of the fact that trinitrons add maybe 30 or more % weight compared to other common curved - semi tubes , so the mounting frame should be rock solid .
another difference is the shape of the tube and the mounting ears. both are manufacturer specific ( trinitron style ) , so it wont be easy to swap a broken tube if necessary . 

after rotation the tv has to cool down and be restarted . or u have to add a second deg coil with a button .

playing vert games on a hor screen isnt a good option , it works somehow , but doesnt feel right .  better start planning on 2 cabs . the sony for hor 2 player setup and a second one for shooters ( maybe something quality branded with a 25 inch philips tube or a smaller one around 20-21 inch . some smaller sonys like 21x4d and x5d are very nice crts for vertical gaming , no matter if its cave sh3 or stoneage mame stuff .


in case ure building a cab from scratch try umsa + scart rgb cable + a keycontroller like ipac or xin mo . jpac-jamma etc doesnt make sense when it comes to mame on a rgb scart tv .