Do I have a bad switching power supply?

ifkz

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Here are the facts: New rebuilt K7000 25 inch monitor. Had this monitor adjusted on another game, full screen, with a fantastic picture. Installed this monitor in another cab (its new home) and the picture is no longer full screen (north & south is smaller with a vertical orientation) and the colors have gotten a little yellower. It also makes a high pitched squeal when power up. It has been capped.

What does everyone think? Bad switcher, perhaps? B+ too high?
 
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You said it all with this line:

"Had this monitor adjusted on another game."

Each game is different. You'll have to adjust for this game.
 
The switcher does not interface with the monitor. Like Peale said, each game is different and sometimes you have to readjust the monitor when you move it between cabs or swap out boards.
 
And don't forget the k7000 requires operation from an isolation transformer. Do both cabinets have a properly wired isolation transformer?
 
Yep, both are pretty standard. One was a Jamma-tized Williams Stargate, the other is a stock vertical Jamma. I would never run without an ISO. I have not measured the B+ after the cap kit. Very odd behavior. I find it strange that I would need to experiment with width caps with one cab, but have my other cab display an almost perfect picture. I tried to adjust the horizontal width coil, but that didn't really help. Also strange that the colors seem a bit off (not degause related either).
 
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are you saying that with the same jamma game pcb the monitor looks different in 2 different cabs or were you using 2 totally different pcb's one in each cab?
 
Two different PCBs. The Williams conversion had Quartet, the vertical JAMMA had Twin Cobra. I'll pull some different PCBs and experiment.
 
Oh yah, screen adjustments would be requited.

Twin Cobra displays at 320x240 @ 55 Hz
Quartet displays at 320x224 @ 60 Hz, Plus there may even be more to the fact that it ran on a 100v nanao, not sure but it may factor in.
 
Wow, how did you figure that out; do you have a link??? Cool info, I never knew! I'll be sure to try some of my other PCBs and report back...maybe it was just Twin Cobra.
 
It's in Mame, I'm betting he got the info from there.

bingo Xmame(well for most of it), Mame may not be great for playing games, it is however a great resource for troubleshooting real arcade games. the sega/nanao stuff you just need to know.
 
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Back on topic: I did the wise thing and metered the input going into the monitor. It is low at 121.7 AC. All of my other games are giving 130 AC at the connector. Now how to fix it?
 
That is not a problem since the chassis is designed for 120vac. I really think you just need to play with the 50/60 hertz pot and the vertical/Horizontal size pots.

Not all games display a picture the exact same size, if they did there would be no need for the adjustments.
 
Your problem IS an adjustment on the monitor, period. It has nothing to do with anything else.

Adjust the monitor to the game you are going to be using it in and be done with it.
 
Your problem IS an adjustment on the monitor, period. It has nothing to do with anything else.

Adjust the monitor to the game you are going to be using it in and be done with it.

He's local to me (I fixes the chassis, too) and I've tested it on my bench (with 120vac and a 60-in-1) and it worked perfectly.

He's been communicating with me via PM and I told him to put the board he got the perfect picture with into this cab so HE knows it's the adjustments for this board, since he isn't taking our word for it...
 
He's local to me (I fixes the chassis, too) and I've tested it on my bench (with 120vac and a 60-in-1) and it worked perfectly.

He's been communicating with me via PM and I told him to put the board he got the perfect picture with into this cab so HE knows it's the adjustments for this board, since he isn't taking our word for it...

Knowing that you repaired the monitor just proves to me that it is just a simple adjustment and NOTHING more.
 
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