Qnic CGM-2500: Various Issues

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My Neo-Geo 4-slot has a QNIC CGM-2500 monitor in it that overall works very well. However, there are a few seemingly minor issues that I fear may become more troublesome over time:
  1. Too much red during warm up period
  2. Screen collapses during bright 'blasts'
  3. Minor 'squishing' near the bottom

Monitor.jpg


1. Too much red during warm up period:

So for item one, while the monitor is warming up, there always appears to be too much red. Though not in the same way as changing the red control. In fact, it's almost like it's dropping red out, then displaying blacks as sort of a maroon color. I've posted a video below of the issue.

After 5-10 minutes, this generally resolves itself. I've also sometimes noticed that 'jiggling' the wires from the chassis to the control board by the CP sometimes makes it come and go, and so does doing the same to the wires going from the motherboard to the chassis. Because of this, I assumed it was a loose connection somewhere, but none were found. Now, jiggling with the wires rarely yields any positive results. Whatevs :p

Any ideas? Should I be concerned? The chassis looks like it was replaced at some point, and from what I can see, all the caps and such look good (pic above).



2. Screen collapses during bright 'blasts'

For item two, I've posted another video below of the same Metal Slug X intro, showing this issue. It's hard to explain, I suppose, but 'collapse' is the best term I could think of. Basically, the screens seems to 'collapse' a bit - or maybe 'jump' - whenever there is a bright flash of light on screen. So in this video, you'll see it twice - once when the logo appears, and once when Marco fires his shotgun.

Unfortunately, I think the camera is too slow to capture the full effect - it's much more noticeable in person. Ironically, this issue does not seem to be present during the warm up period when issue one is occurring.

(As an aside, this video shows the intro after the warm up issue shown for item one resolves itself - so you can see how the red in the warning screen at the beginning actually appears to have been dropped out in the video above)



3. Minor 'squishing' near the bottom

And lastly, for item three, if you watch either of the videos above, you'll notice the horizontal line just above the credit counters. Anything below this line seems 'squished' and is really noticeable when there's scrolling text or something on screen. I've been unable to correct it with any of the adjusters so far.

Any help for any of these is appreciated. Even just thoughts or general suggestions :)
 
Others' approach may vary, but I'm of the opinion that it's best to start with a cap kit and go from there. Generally, it takes me longer to diagnose a specific issue than it does to break out the soldering iron and replace the components that fail frequently.

If that fails to fix it, then you start figuring out what else is wrong. And you know it's not the caps, and won't be the caps for a few years at least.
 
Others' approach may vary, but I'm of the opinion that it's best to start with a cap kit and go from there. Generally, it takes me longer to diagnose a specific issue than it does to break out the soldering iron and replace the components that fail frequently.

If that fails to fix it, then you start figuring out what else is wrong. And you know it's not the caps, and won't be the caps for a few years at least.

True. This is my general approach as well (with the few monitors I've had over the years, anyway). I'm in the process of noting everything I need from Bob right now anyway, so I can make one big order sometime soon. Figured I'd just throw this out there now in case anyone had any ideas.
 
True. This is my general approach as well (with the few monitors I've had over the years, anyway). I'm in the process of noting everything I need from Bob right now anyway, so I can make one big order sometime soon. Figured I'd just throw this out there now in case anyone had any ideas.

The only other thing I'd check are the pots on your remote board, and the header pins on its connectors (on the remote board and the chassis).

My Neo-Geo also has a QNIC with a swapped chassis… Except someone swapped in a K7000.
 
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