| View previous topic :: View next topic |
| Author |
Message |
Zebra
Joined: 02 Jul 2020
Posts: 87
Location: NJ USA
|
 Link Posted: Sun Sep 06, 2020 11:27 pm Post subject: |
 |
|
| banzairun wrote: | So you're just using a Playstation that you want to project? or are you using arcade guts?
Time Crisis deluxe (1-3) all used off-the-shelf consumer-grade 50" Mitsubishi PTVs. The game boards feed RGB to a S-video board for the PTV input, so many front projectors will be able to take that input directly. I've owned a pile of the arcade games and would usually just grab free/cheap mits sets to "retube" them, rather than actually retubing the sets, as I do with the Toshiba & Hitachi sets for Sega arcade games.
I wouldn't put much thought into which projector you use if you want to use a front projector to play around with. The shittier the projector, the less tight focus it will have, if that is what you are looking for, but the older projectors won't be as bright. The better the projector, the more space you'll have between the scan lines (projection CRTs don't have a dot-pitch, as previously stated), so this is why people used line doublers and scalers back in the day; it wasn't to "increase resolution" as some seem to think, since you can't actually do that. It just adds more scan lines to the image, meaning it's using more of the tube face, and hence more light thrown to the screen.
If you can find a Barco 7-series, those are probably the best 7" sets, are small and have good light output. You can directly feed a CRT projector (or your Ikegami) video from an arcade board as long as you use a level shifter PCB (games output 3-5vp-p and consumer gear expects .7vp-p signal levels). Sega made them for all their projection games, so they're pretty easy to source, or you can just use a Gonbes 8200 in the signal chain (they're junk, but are cheap and work). The Ike' might be okay with higher video input levels - some PVMs are OK with it, but it's better to level-shift it down to the standard level if possible.
You can always de-focus the image slightly if you're sensitive to how sharp the image looks. This is sometimes done with CRT projectors (particularly with the blue tube) just to brighten the image a little bit. You can do it with your Ikegamis as well if it's bugging you. If you have any Nanao monitors in your 27" games, those used the best tubes of anything you'll have around and they tend to last a while. K7000s look fine, but the Zenith tubes in most of them very commonly have soft focus and weak color guns - I've re-tubed probably 100 of them at this point from TV sets. The later ones with RCA tubes generally have good tubes.
For arcade monitors, the dot pitch on most tubes 25" and up will all be roughly the same, it was only often on the smaller tubes they actually made them with a finer dot pitch. 24kHz (medium resolution, or "EGA" from the PC-world) 19" arcade monitors used M48 CRTs instead of A48 CRTs, since the finer dot pitch of an M-series CRT makes a difference, but 25" medium res monitors all used the same standard A63-size CRT, no matter the resolution.
I guess I have some insight here as I've had a pile of CRT projectors and still have about 1000 arcade games, so I've mixed them together a few times over the last 25 years, but I generally just play with dedicated games these days, and don't even have a CRT PJ set up at the moment, even though I still have about a dozen sitting around.
Also, just FYI: your "29" monitors" are actually 27" (A68-size CRTs), we're in the USA, we measure viewable area, not total tube envelope size. Only Japan calls them 29s. |
I use a bunch of different systems but my main 15khz sources are a bunch of Arcade PCBs (with a supergun when used outside a cab), a PS2 and a PC running CRTEmU drivers + Groovymame. I use RGB for all 240p/480i, 384p and 480p games.
My Tri-sync crt monitors all have a switch for either .7v consumer rgb or 3-5v ttl arcade boards. I use the supergun for displays that can only handle .7v and RGB boosters for monitors that look too dim with .7v rgb.
Pretty much all of the late model arcade monitors used tubes with a finer pitch. My old K7000 had a pitch around .95mm. My 24.8" billabs uses a flat Toshiba tube with a .68mm pitch and I have a 29/27" Makvision tri sync with a .78mm LG tube. Same with the Samsung Tube on the Kortek I just pulled from an America's Army cab. They're not as fine as the .3mm Ikegami tube but definitely not as nice as my K7000 for 240p. I love those old curved CRTs.
I'm not sure blurring the image on a CRT projector will achieve my goal. The image on my Wells Gardner monitors is crystal clear. It's pitch is just right for the content. Those jaggies are not from extra clarity. It's a mismatched pitch. You get the problem even on the cheapest lowest quality crt pc monitors if the pitch is too fine. It's like if you increased the size of a low res thumbnail image until it looked pixelated, blurring the image wouldn't solve the problem. It would just look pixelated and blurry.
Anyway, if no such issue exists on CRT projectors then I only have to worry about whether it's bright enough for light guns to register on a 50"-60" 4:3 screen.
I've just been checking out deals on some of the later 7" Sony and Barco units. It's amazing to see the unrealistic expectations some people still have on what they're worth. How long would you leave a listing up before you realize that nobody is going to pay $1000+ for a 480i only crt projector??? They seem to have this simplistic thought process like "it's original rrp (in 1994) was $12,000 so $1,200 is a real bargain now".... I guess I'll have to be patient if I want anything good.
|
|
| Back to top |
|
 |
AnalogRocks
Forum Moderator
Joined: 08 Mar 2006
Posts: 26690
Location: Toronto, Ontario, Canada
TV/Projector: Sony 1252Q, AMPRO 4000G
|
| Link Posted: Mon Sep 07, 2020 5:55 am Post subject: |
|
|
My Ampro 4000 in 1993 $60 000, my Ampro 4000 2006, $1600. Next two were free.
Just an FYI Ampro 4000 will fit in the trunk of a Crown Vic. 
_________________
Tech support for nothing
CRT.
HD done right!
|
|
| Back to top |
|
|
Zebra
Joined: 02 Jul 2020
Posts: 87
Location: NJ USA
|
| Link Posted: Tue Sep 08, 2020 3:34 am Post subject: |
|
|
Does anyone here know anything about the Barco 7120a? It's not listed under the Barco specs page on this site and I can't seem to find much online beyond some superficial info.
It's apparently a (monstrously large) 9" model with the largest power requirement I have ever seen on a projector. They say it needs a 240v 18a power supply (comparable to my 7.5hp cnc spindle motor). Is this the brightest CRT projector ever made? If not, why does it require enough power to turn a small planet?
Barco describes it as a "raster calligraphic" Projector. I thought most crt displays were raster (besides vector arcade monitors) but what does the "calligraphic" part mean?
The sales sheet doesn't list brightness or contrast specs or max resolution / refresh rates etc. Has anyone here seen one or know it's specs?
|
|
| Back to top |
|
|
AnalogRocks
Forum Moderator
Joined: 08 Mar 2006
Posts: 26690
Location: Toronto, Ontario, Canada
TV/Projector: Sony 1252Q, AMPRO 4000G
|
| Link Posted: Tue Sep 08, 2020 4:38 am Post subject: |
|
|
Every couple years someone discovers the 712. 460-480lbs, 12 inch tubes. GM had 3 of them that some one got surplus about 10 years ago. There was also a man in Japan that had one in his living room. Looked crazy impressive.
The 12" tubes were brighter than the 9" but the 9" was sharper.
_________________
Tech support for nothing
CRT.
HD done right!
|
|
| Back to top |
|
|
kal
Forum Administrator
Joined: 06 Mar 2006
Posts: 17859
Location: Ottawa, Canada
TV/Projector: JVC DLA-NZ7
|
|
| Back to top |
|
|
AnalogRocks
Forum Moderator
Joined: 08 Mar 2006
Posts: 26690
Location: Toronto, Ontario, Canada
TV/Projector: Sony 1252Q, AMPRO 4000G
|
| Link Posted: Tue Sep 08, 2020 5:40 pm Post subject: |
|
|
| kal wrote: | | Zebra wrote: | | Does anyone here know anything about the Barco 7120a? |
Someone was asking ~2 weeks ago: http://www.curtpalme.com/forum/viewtopic.php?t=42495
I believe they may only be 9" tubes however, not 12".
There were some rare models with 12" tubes that were built for increased light output and everything Jeremy wrote about this is right (they were not as sharp).
Kal |
Doh! Sorry, I should pay more attention to the model numbers! I was thinking of the 912 https://www.barco.com/en/product/barcoreality-912
The vertical projectors were used in the flight sims to project HUD'S, and targets from what I remember reading here. Looks like 9" tubes. I seem to remember Barry and I talking about use in video games because these weren't a raster scan. Something more like Asteroids. You'll have to do some more digging and I'll try remembering harder until the smoke comes out my ears.
We had a whole post about these 12-13 years ago. Not sure it's still online now though.
Sorry for my lack of reading model number comprehension.
_________________
Tech support for nothing
CRT.
HD done right!
|
|
| Back to top |
|
|
Zebra
Joined: 02 Jul 2020
Posts: 87
Location: NJ USA
|
| Link Posted: Tue Dec 08, 2020 9:35 pm Post subject: |
|
|
| AnalogRocks wrote: | | kal wrote: | | Zebra wrote: | | Does anyone here know anything about the Barco 7120a? |
Someone was asking ~2 weeks ago: http://www.curtpalme.com/forum/viewtopic.php?t=42495
I believe they may only be 9" tubes however, not 12".
There were some rare models with 12" tubes that were built for increased light output and everything Jeremy wrote about this is right (they were not as sharp).
Kal |
Doh! Sorry, I should pay more attention to the model numbers! I was thinking of the 912 https://www.barco.com/en/product/barcoreality-912
The vertical projectors were used in the flight sims to project HUD'S, and targets from what I remember reading here. Looks like 9" tubes. I seem to remember Barry and I talking about use in video games because these weren't a raster scan. Something more like Asteroids. You'll have to do some more digging and I'll try remembering harder until the smoke comes out my ears.
We had a whole post about these 12-13 years ago. Not sure it's still online now though.
Sorry for my lack of reading model number comprehension. |
If "calligraphic" means it's like a vector arcade monitor then Barco describing them as "raster calligraphic" may mean it's a kind of dual mode projector that could be used for either. This would make it even more desirable for old arcade games.
But, when I try and read Barco's limited blurb on these, it sounds like they mean something else entirely. It sounds like some feature to make the image brighter. It really makes no sense at all though. The power draw in particular seems crazy.
You'd think it was common terminology the way their marketing literature provides so little explanation but that is 100% typical for Barco. I think they may have the worst marketing team on earth.
They never even bother to explain the benefits of their $50,000-$100,000+ projectors.
Anyway, looking closely at the pics on ebay, the label on those 7120's says 1209. So maybe it's a modified (or not so modified) version of a regular 1209.
The only input on the back I can see is a single set of RGB BNC ports. I can't even see a sync port, so maybe they only accept RGsB.
|
|
| Back to top |
|
|
garyfritz
Joined: 08 Apr 2006
Posts: 12025
Location: Fort Collins, CO
|
| Link Posted: Tue Dec 08, 2020 9:51 pm Post subject: |
|
|
| Zebra wrote: | | But, when I try and read Barco's limited blurb on these, it sounds like they mean something else entirely. It sounds like some feature to make the image brighter. |
That's possible. When you have a current-limited device like a CRT, painting the whole raster can really limit the brightness you can get. The amps/electrons are spread over a big area so the big area can't be very bright. But a calligraphic display doesn't paint the whole raster -- just the strokes of whatever it's drawing. So those lines that are drawn for your 3-d wireframe model or whatever can be much much brighter.
|
|
| Back to top |
|
|
Zebra
Joined: 02 Jul 2020
Posts: 87
Location: NJ USA
|
| Link Posted: Sun Dec 13, 2020 6:42 pm Post subject: |
|
|
| garyfritz wrote: | | Zebra wrote: | | But, when I try and read Barco's limited blurb on these, it sounds like they mean something else entirely. It sounds like some feature to make the image brighter. |
That's possible. When you have a current-limited device like a CRT, painting the whole raster can really limit the brightness you can get. The amps/electrons are spread over a big area so the big area can't be very bright. But a calligraphic display doesn't paint the whole raster -- just the strokes of whatever it's drawing. So those lines that are drawn for your 3-d wireframe model or whatever can be much much brighter. |
Perhaps I don't understand how vector monitors work but I always assumed they were all monochrome by necessity. If this isn't the case then it's possible that the 7120's extra brightness is only when it's used in vector mode. It doesn't explain why it uses 8 times more power than a regular projector though. The 7120 takes an RGB signal which I haven't seen on any arcade vector monitors.
The way Barco describes it, it sounds like a "calligraphic image" is overlaid across a regular raster image but this made even less sense to me. I tried thinking about what it could mean and it gave me a nose bleed so I decided it was beyond my understanding without further info.
|
|
| Back to top |
|
|
garyfritz
Joined: 08 Apr 2006
Posts: 12025
Location: Fort Collins, CO
|
| Link Posted: Sun Dec 13, 2020 6:51 pm Post subject: |
|
|
Google "calligraphic CRT projector" and you'll find a number of articles and papers. Might still make your head explode. 
|
|
| Back to top |
|
|
Zebra
Joined: 02 Jul 2020
Posts: 87
Location: NJ USA
|
| Link Posted: Thu Dec 17, 2020 6:16 pm Post subject: |
|
|
| garyfritz wrote: | | Google "calligraphic CRT projector" and you'll find a number of articles and papers. Might still make your head explode. |
I did and it did...
I didn't find anything helpful for explaining what it meant in terms of Barco's flight sim crt projectors that use more power than a small star though.
|
|
| Back to top |
|
|
Curt Palme
CRT Tech
Joined: 08 Mar 2006
Posts: 24301
Location: Langley, BC
TV/Projector: All of them!
|
| Link Posted: Thu Dec 17, 2020 6:27 pm Post subject: |
|
|
Simple.. no scanning lines. Back in the 80s there was a video game where your plane shot at shooting stars. It was done via a vector display, and at the time it was the sharpest looking image out there. BAck then I had no idea why until I got into the CRT thing, and someone explained it to me.
There was a company also manufacturing a vector planetarium display that I saw about 15 years ago. Same thing, no scanning lines, no raster, and CRT tubes that were absolutely stupidly expensive.
|
|
| Back to top |
|
|
gjaky
Joined: 05 Jun 2010
Posts: 2790
Location: Budapest, Hungary
|
| Link Posted: Thu Dec 17, 2020 8:56 pm Post subject: |
|
|
| Zebra wrote: | | garyfritz wrote: | | Google "calligraphic CRT projector" and you'll find a number of articles and papers. Might still make your head explode. |
I did and it did...
I didn't find anything helpful for explaining what it meant in terms of Barco's flight sim crt projectors that use more power than a small star though. |
The power consumption is mostly coming from the deflection circuits. In a raster scanning CRT display the horizontal scan is usualy done by a resonant flyback circuit which is rather efficient. Still if the scanning frequency is high the deflection coils can take up several hundred Watts of power. Vertical deflection is less demanding as the scanning frequency is not so high, sometimes low power (~20W) audio amplifier ICs are used for such purpose.
In a calligraphic display you want full control over both vertical and horizontal deflection this only can be done with linear amplifiers, which are nowhere near as efficient as a flyback circuits, plus you have now the same speed requirement for the deflection for both planes.
_________________
projectors in the past : NEC 6-9PG xtra, Electrohome Marquee 6-7500, NEC XG 1351 LC ( with super modified Electrohome VNB neckboard !!!)
current: VDC Marquee 9500LC
The MOD: VNB-DB, VIM-DB
|
|
| Back to top |
|
|
garyfritz
Joined: 08 Apr 2006
Posts: 12025
Location: Fort Collins, CO
|
| Link Posted: Thu Dec 17, 2020 9:35 pm Post subject: |
|
|
| Curt Palme wrote: | | Simple.. no scanning lines. Back in the 80s there was a video game where your plane shot at shooting stars. It was done via a vector display, and at the time it was the sharpest looking image out there. |
Are you thinking of Asteroids? https://www.youtube.com/watch?v=_TKiRvGfw3Q
It was a vector display. You can see bright spots anywhere two lines intersect, because the phosphor got drawn on twice.
There was also Battlezone, a two-player 3-D tank-battle game. https://www.youtube.com/watch?v=Ctr54kopo8I.
Those games came out in Nov 1979 and Nov 1980. Gaming has advanced a bit since then...
|
|
| Back to top |
|
|
Curt Palme
CRT Tech
Joined: 08 Mar 2006
Posts: 24301
Location: Langley, BC
TV/Projector: All of them!
|
| Link Posted: Fri Dec 18, 2020 12:55 am Post subject: |
|
|
|
Yes, Asteroids. Couldn't think of it earlier. They made a small tabletop version for $99, I almost bought it just to tear it apart.. but didn't.
|
|
| Back to top |
|
|
kal
Forum Administrator
Joined: 06 Mar 2006
Posts: 17859
Location: Ottawa, Canada
TV/Projector: JVC DLA-NZ7
|
|
| Back to top |
|
|
AnalogRocks
Forum Moderator
Joined: 08 Mar 2006
Posts: 26690
Location: Toronto, Ontario, Canada
TV/Projector: Sony 1252Q, AMPRO 4000G
|
| Link Posted: Fri Dec 18, 2020 4:44 pm Post subject: |
|
|
Hey! My Friday night playlist!
_________________
Tech support for nothing
CRT.
HD done right!
|
|
| Back to top |
|
|
thehockeytowner
Joined: 02 Apr 2020
Posts: 18
|
| Link Posted: Sat Dec 19, 2020 12:45 am Post subject: |
|
|
Tempest was and is terrific!
_________________
Go Wings!
|
|
| Back to top |
|
|
garyfritz
Joined: 08 Apr 2006
Posts: 12025
Location: Fort Collins, CO
|
| Link Posted: Sat Dec 19, 2020 2:35 am Post subject: |
|
|
|
I would have sworn Tempest was a raster based game. My memory of the game, unusually sharp for some reason, has pixels. But the wiki page says it used Atari's Quadrascan vector display. On the other hand another wiki page says Quadrascan was a shadow mask technology, soo...
|
|
| Back to top |
|
|
jask
Joined: 17 Mar 2006
Posts: 10165
Location: kamloops BC
|
| Link Posted: Sat Dec 19, 2020 4:00 am Post subject: |
|
|
|
wow! this just reminded me of Breakout.. and that whole connection to Woz , Jobs and RBG that Atari inspired.
|
|
| Back to top |
|
|
|
|
Forum FAQ
Search
Memberlist
Photo Albums
Register
Profile
Private Messages
Log in
