CurtPalme.com Home Theater Forum

[CasetheCorvetteman]

There is a cross hatch and coloured boxes of an MVS, more with a UniBIOS installed.

[banzairun]

Resistors should work fine.. but I'd suggest maybe grabbing one of these if you wanna interface arcade games to a projector with .7v inputs. All Sega 24kHz (15khz would surely work fine) deluxe projection games use one of these level shifter boards to convert the signal down to .7v, and since most of these games get junked when the tubes get worn, they're pretty easy to find and not really worth anything since nobody needs them these days.

I just did a quick ebay search and didn't see one up, but I'd keep an eye out.. RGB in is on the 6-pin .100 header, 5VDC in on the 3-pin header, and BNC out to the projector.

When projection arcade games get LCD-hacked everybody pulls these boards out and hacks in one of those 24k-->31.5k scan converters you can get on ebay for $25 -- that's another option if you want a simple 31.5/VGA output to feed a projector.

[uncletom]

Interesting, Banzai. And is that board powered? I can see transistors. I really looks like an amplifier...

Wouldn't it just be simpler to choke the RGB with a few resistors, perhaps inside a heatshrink?

[banzairun]

[CasetheCorvetteman]

Pointless, 220 ohm resistors do the same job. Fine if youve allready got the board from a Sega deluxe cab, but i sure as hell wouldnt buy one.

[uncletom]

Thanks Banzai. I understand. I'm sure it does the job well. I've just always used resistors when adapting TTL-RGB to 0.7vpp for TVs, and people with these 'Superguns'.

Thinking about it; every monitor and projector in deed should have this kind of RGB strength regulation onboard. My experience with most arcade monitors is that their specs are 1.5 - 4 (or 5) V RGB levels. Why not just have it ranging from 0.5V?

On a side topic now, that is infact why I like the older arcade monitors from Hantarex better than the newer ones, take the MTC900, it takes just about any RGB-level and you can regulate the input by the onboard tripple-pot at the inputs. You can even invert the RGB and sync onboard with a connector, or jumpers on the 900E. I've recently restored an old MTC900E and I feel it's the finest monitor I've ever worked with, functionwise and picturewise.

[banzairun]

[CasetheCorvetteman]

No im familiar with it, i have a spare here from Star Wars Deluxe and the Ocean Hunter Deluxe cab here has it as well. But for the sake of 3 resistors, i wouldnt bother with that device in the chain if it wasnt factory fitted.

[uncletom]

Yes, that's what slightly bothers me incorporating the active RGB level-shifter, it would be yet another device to consider.

I guess SEGA used it because BP-monitors have that much larger picture, which in turn requiers more precise control in every aspect. What they could do, and have done on Virtua Fighter 2, is to simply lower the output of the game hardware. In the game assignments you can infact select "CRT" or "Projector".

I just had a look in a manual for SEGA's "Megalo 2" cabinet. Their BP-monitor is 24kHz only, and any 15k signal is converted to a 24 khz.n Strange. There were dual and tripple sync monitors then.

I always find chatting about old monitors very intriguing. If you guys don't mind I'll create a thread about the Hantarex MTC9... model.

Give me a moment.

[CasetheCorvetteman]

That setting in the Model 2 hardware ( its in all the Model 2 games ) makes the screen brighter for projector if i remember right, on Daytona and some others it is chosen when selecting the cab type, Twin/Uplight or Deluxe etc...

[uncletom]

Brighter? I see. Very interesting.

[CasetheCorvetteman]

I think the first Megalos had a converter to drop RGB to s-video, i had one of those here a while ago.

[uncletom]

Just like a regular TV then. Well, I've never had the opportunity to feel one of those anyway. I don't think I'd care much for the BPTVs, image only visible from straight on position, and with really uneven intensity across the screen. Kind of reminds me of a bad hologram. Size just isn't everything.

[CasetheCorvetteman]

Not always, depends on the brand. I never had that issue with any of mine.

[uncletom]

Ok, but if you compare it with a regular CRT monitor? Isn't the BPTV so much lower picture quality?

It has been a while since I saw one out in an arcade, and then I wasn't really impressed.

[banzairun]

You might be thinking of Namco, which used an RGB to S-vid converter in their projection games for all of the 90's.

I have about a dozen deluxe cabs including Virtua Fighter 1 2 and 3. VF1 was one of the first projection cabs* (and was Sega's first I believe), released in 1993, predating the Super Megalo, and uses basically the same mits chassis that VF2 & 3 used, though VF1 is 40". Sega fed the sets RGBS from the beginning, and switched to VGA on the post-Model1/2/3 hardware.

Yeah uncletom, The projection monitors can look great... when they are in good condition, Though if you've seen any projection game in an arcade it's guaranteed to look like crap at this point, the tubes are gonna be tired. All the monitors Sega ever used have pretty good brightness uniformity, though the fresnel will still throw more light your way if you're directly in front. I have an 8-player game with 50" screens and despite the screen being effectively 9 meters wide across the 8 screens, it looks great from pretty much any angle that isn't toward the extreme oblique. In a playing position, the monitor's picture throw is not something that you'll even consider as a concern.

I would not consider a projection set with good tubes to be of much lower-quality than a direct view -- they can look very good. Direct-view is clearly superior, but if you want a large screen, they're fine for what they are. If they were awful enough that nobody wanted to play deluxe games, nobody would have bought games with them when they were new, though they certainly don't age well. Corner focus is the other weak point, as you'd expect. I'm fine with how they look, though in many cases I'd prefer the standard game over the deluxe.


*some games in Japan from '82 or so were sold with Novabeam projectors, and American Laser Games had 50" monitors in their deluxe LD-based machines starting about 1990, though they were also just standard low-end consumer sets fed via composite.

[uncletom]

Good info, thanks. Looks like you have first hand experience with the BP-monitors.

That 8-player game you refer to, would that be the Daytona?

[CasetheCorvetteman]

Yes, thats is Daytona

I set up a small Deluxe link here a while ago with a Tau GIGA and an LG:

[uncletom]

Wow!...

But you are using PC to emulate it? Or you run the game from Model2 hardware?

[CasetheCorvetteman]

Nebula Model 2 emulator and G25 wheel. Set up right, its pretty near the same to play.