Build Your Own Arcade Controls Forum

Main => Monitor/Video Forum => Topic started by: colin on June 13, 2005, 12:04:41 am

Title: Tetris video problem help
Post by: colin on June 13, 2005, 12:04:41 am

I have a Tetris JAMMA PCB that seems to be doing everything fine except the video.  Looks like video is scrolling rapidly upwards, similar to a VCR tracking problem.  I have two other JAMMA boards that work fine in my cabinet.  Any idea what the problem might be and how it can be fixed?

Title: Re: Tetris video problem help
Post by: pcb on June 13, 2005, 03:30:26 am

Check for continuity between the Video Ground finger on the board and ground.  Sounds like a Video Ground problem. 

Title: Re: Tetris video problem help
Post by: RayB on June 13, 2005, 03:39:24 pm

Keep in mind that although different boards might adhere to the JAMMA pin-out specification, that doesn't mean they all adhere to the same standards for signal strength, etc...

From one board to the next, volume could vary, brightness could vary, and yes, the vertical hold may need slight adjusting.

Title: Re: Tetris video problem help
Post by: colin on June 18, 2005, 04:09:19 am

Where can I find out how to adjust this vertical hold?  The only adjustable thing I've noticed is a pot that controls volume.  Are there components that might need changing?

Title: Re: Tetris video problem help
Post by: colin on June 18, 2005, 04:12:10 am

PCB,

I'll check out your suggestion as well.  If that is a problem, should I just connect them or would it suggest a fried component that needs replacing?

Title: Re: Tetris video problem help
Post by: RayB on June 18, 2005, 11:27:58 am

Quote from: colin on June 18, 2005, 04:09:19 am

Where can I find out how to adjust this vertical hold?