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Pacman/Galaga 20th & 60-in-1 Multigame Bartop Build

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CraftyMech:
I need to sit down and start working on the cabinet plans, but in the mean time I did some more work on my scanline generator.

I remember back in the '80s I used to stare at the soft glow of the arcade monitors and wonder why I couldn't get the graphics on my Commodore 64 at home to look like that on my tv. A scanline generator (or the "scanlines" option in MAME), brings back some of that old arcade monitor feel, but those soft glowing edges are missing.

So I modified my scanline generator to also manipulate the RGB signal to introduce what I'm going to call "bleed". The bleed kicks in for the most part where edge transitions are harsh, like white text on black, the edges of the walls in a PacMan maze, etc. Injecting bleed on all three signal lines sort of cancelled itself out, so I'm currently testing bleed on just red & blue.

The photos below show the effect, with the right image of the "High Score" label in Ms. Pacman captured while running bleed on the blue/red signals, and the left image as just plain scanlines with no signal manipulation.  The photos are straight from my camera, with just cropping and resizing and no other manipulation.

I'm still playing with the component values, but I like the effect, it worked better then I expected and brightens up the image a bit  and adds some of that glow I always loved as a kid.

Malenko:
I have no idea how they did it, but if you have a 360 check out Final Fight on xbox live arcade, they have some CRT monitor effects (like Phosphor glow) that are just flat out awesome.

CraftyMech:
I'll have to check Final Fight out.. I like the xbla classics, for the most part the developers have done a good job with the emulation.

The phosphor bleed effect I built is a tweak to the analog circuit, but it sounds like the developers of the xbla Final Fight game used a custom graphics engine that simulates the appearance of the old arcade monitors. I hope that trend catches on, the other xbla classics I have played rendered the screen in the right proportion (letterboxed) but didn't offer even a software scanlines option.

CraftyMech:
Time to get the show on the road and de-case the display to see what kind of footprint the 14" CRT monitor will have.

The monitor is shown in the normal horizontal position in the photo, supported by the remains of the pc motherboard case. I'll be turning the monitor on its side for a vertical orientation, so the first problem I had to solve was how to reinforce the structure once that bottom section of U shaped metal sheeting was removed. Naturally that plate was what held the three separate pcbs of the monitor/power supply assembly together, so I had to put my thinking cap on for a bit.

CraftyMech:
Working late into the early morning hours, I came up with a sub-frame for the monitor built from aluminum angle & box channel. An early challenge was how to position the monitor vertically, and at the same time allow it to tilt back at an angle. In the horizontal position, the monitor already had a slight angle of layback, so I would need to counteract that angle as well so that when viewed vertically there was not a side-to-side lean.

I came up with a sturdy frame that included posts in front of the right height to cause the tube casing to angle back about 10 degrees. On the back end I put a swing arm (anchored by a 1/4" bolt) that allowed me to skew the whole assembly a few degrees from square, which eliminated the layback that was present in the horizontal configuration. So by the end of it all I had a nicely orientated vertical monitor, mounted on a solid rebuilt chasis. There was much cutting, grinding, some bleeding, and a little cursing.

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