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Main => Monitor/Video Forum => Topic started by: spyhunter on December 08, 2007, 06:15:41 am

Title: Spy Hunter on LCD
Post by: spyhunter on December 08, 2007, 06:15:41 am
Hi guys, just looking for some advice to get an LCD that I've already installed in my SH sitdown machine working.
 
The LCD I have is from http://www.slotsdirect.com/lcdmon.html and while it can sync at 15KHz horizontal sync, it is not able to sync with the 30Hz vertical / interlaced video signal.  The picture appears on the screen, but it is very dark and blurry, and screen adjustments have little or no affect on it.

From what I can tell I need a deinterlacing device to give the LCD a progressive or 60Hz signal, but I've heard that this may not work very well since LCDs need more precise syncing than CRTs.  I'm thinking there's gotta be a device that can see the game clearly and then just present it to the LCD, and I'm in search of this device or any other way to get my game running, such as a different LCD.  I never thought this would be such a hard issue to resolve.

Do replacement CRT monitors for this game and others that use the MCR system really need to have a vertical frequency range of around 30Hz?  Because the ones I've looked at on the net, only go down to around 45Hz.

Thanks very much for your help!  I can't wait to get this thing going...

Tim
Title: Re: Spy Hunter on LCD
Post by: qrz on December 08, 2007, 08:59:21 pm
i would think the game should have 60 hz vert rate when paired w/15 khz horiz .
this is a standard ntsc scan rate.
if u see a "picture" rather than scan lines/ rolling . sync is not the issue.
this monitor supports 6 different scan modes .
try the cga/ega/vga settings first . since svga is listed,
u could try connecting it to a pc to verify operation......

qrz
Title: Re: Spy Hunter on LCD
Post by: spyhunter on December 09, 2007, 08:24:29 am
I've tested it with a PC and it's fine, I'm pretty sure the problem is interlacing and most LCDs can't handle an interlaced signal.  It thinks it's only 30Hz, when it's actually 60Hz interlaced.  But then I've seen some posts on this forum and the Bally Midway MCR games were very different from the rest.

I don't think an LCD would ever roll, but as blurry as it is, they could be scan lines?  As far as I can tell, there's no way to select a resolution, it's automatically chosen.

Tim
Title: Re: Spy Hunter on LCD
Post by: spyhunter on December 20, 2007, 08:43:12 am
I spoke to a techy at Happ Controls today and he told me some mumbo jumbo about needing to use a CRT yoke and that it has a need to be placed the correct way, and because of this an LCD would never work, but I still think it lies with this 30Hz thing...

SH
Title: Re: Spy Hunter on LCD
Post by: SavannahLion on December 20, 2007, 04:47:30 pm
I spoke to a techy at Happ Controls today and he told me some mumbo jumbo about needing to use a CRT yoke and that it has a need to be placed the correct way, and because of this an LCD would never work, but I still think it lies with this 30Hz thing...

So stick a CRT yoke on the LCD and be done with it.  ;)
Title: Re: Spy Hunter on LCD
Post by: spyhunter on February 05, 2008, 02:47:25 pm
Hey guys, any new ideas?  Thanks!  There's gotta be a way to get these Midway games to display on something other than their original CRTs, I refuse to believe that they are CRT exclusive.  The installed LCD in my game is just too sweet to give up only to go back to the dinosaur of a CRT that was in it.

I've since tried this rgb to vga converter which is essentially the same thing built into the LCD and no change:

http://www.ambery.com/rgbcgatovgac.html

SH