Problem with composite Input, Please Help

[PacManFan]

Hello everyone,
I'm building a mame cocktail ms. Pacman Replica, I'm using a 19" Magnavox TV I picked up from a thrift store. I'm using the composite input on the tv, and I get a bunch of Wavy lines every few scanlines or so.
To test what is going on, I have hooked up a composite to rf modulator and also sent the signal in on channel 3. When I use the RF modulator, I have no more wavy lines and the picture looks steady, except it suffers from a lot of color bleading and static on the screen whenever the screen mode changes.
Why is the composite input producing such a crappy wavy picture? How com I am not getting this on the RF 300 ohm signal in? I thought after the signal was demodulated from RF, it passed thought the same circuitry.

Any help would be useful?
-PacManFan

[tom61]

Try a better video cable. Low-quality cables tend to make wavy lines when used with a computer's TV-out.

[PacManFan]

A better video cable was one of the first things I tried. I am using a gold plated shielded 3 foot 15$ cable.

I also ran out to radio shack to see if I could boost picture quality by putting in a video amp. I bought a 4 - way distribution amp from Radio Shock, that could convert from s-video to composite and composite to s-video. My tv did not have s-video in, but I went from the svideo on the ATI card to the distribution amp, and used a composite cable from the amp to the TV.
Still, no effect.

Could this be bad capacitors? If so, why does it only show up on composite in and not the 300 Ohm input?

I have used this video card in another previous MAME cabinet until I upgraded, with no problems. I don't think it's the card or a weak signal.
I might not mind the color bleading so much on the 300 Ohm input , but the static on the screen between screen mode changes is unacceptable. Is there a device that can block the static out and display a blue or black screen like a good VCR does?

-PacManFan