RGB inputs changing

[shardian]

I have a Xevious cabinet with Jamma and a 48-1 board, and a g07 monitor.

Here is some info from another thread:

I have a G07 monitor issue in my Xevious. The colors are all wonky after doing a tube swap, and I'm not sure what is wrong.

Anyways, the 48-1 has a color pattern test screen, but with one problem. I have no clue which colors are supposed to be where. Could someone up a photo of a correct pattern, or at least tell me what the pattern is supposed to be?

And if anyone wants to help troubleshoot: the tube was known good, and the wiring is verified. The chassis might be suspect because I think the colors may have been wrong before the tube switch, but the game (relief pitcher) didn't make it easy to see all colors.
All colors show up in "Happy Hours" on the game select screen, though green is a little light. The tube is also obviously magnetized and needs manually degaussed. I've been told the colors wouldn't be thrown off as bad as they are by magnetism though.
Problem solved. Even though I verified the Jamma pinouts, and verified the G07 rgb pinouts on Bob Robert's site, the pins were still wrong. Who knows why? I just kept changing the order until the colors were right.

Bob Robert's G07 page: Pin1 Pin 2 Pin 3
                                         R      G      B
My G07:                            G      B      R


Still has a magnetized splotch, but it is getting smaller with each fire up I think.

I turned the machine 180 and then pushed it up against the wall. 2 hours later, I turn it back on. THe colors are messed up again. I end up having to switch the RGB wires back to the original (correct) arrangement!

Can someone (Ken) please explain what is going on here?

[Kevin Mullins]

Sounds like you need to check to see if the degauss is also working.

[shardian]

How do I check that? It is plugged in and the coil is in place around the tube. The screen crackles when it comes on. even if it isn't working, could that really completely change the color inputs?

[grantspain]

if the degauss is not working you will get two different faults,either you will have some minor discolouration(normally in the corners) if the degauss is not kicking or disconnected and the other will be a complete mess of the colours which can happen if the ptc component blows

best to leave it off for a few hours to see if the deguass kicks back in on cold start up

the only other thing that would cause something similar is when the shadow mask is out of place but that only happens when a crt takes a big impact

[shardian]

Well I have it against the wall in its main resting place - all colors intact. There is slight magnetism on the far right side, which never goes away with cold reboots. i suppose I can assume the degauss system is screwed...which makes no sense considering it is a crude coil with straight AC power. How does one screw that up?

[grantspain]

ptc component is knackered or you have a serious magnetic field nearby

[shardian]

Can you elaborate on this 'ptc component' thing? I don't think there are any magnetic sources nearby. There are 2 speakers in a Xevious, but neither is too close to the monitor, and the lower speaker is on the opposite side of the discoloration.

[Kevin Mullins]

It's basically a thermal resistor (posistor) that will conduct (turn on) electricity until it reaches a certain temperature/resistance and then it will "open" (turn off).
In your case it's the little black box right near where the degauss coil plugs in.
Best to check out of circuit... using an meter check for ohms/continuity across the two pins.
When cold it should give a reading, when hot it should be open. (not sure what the actual resistance is on that one)
You can also just unplug the coil and insert your meter to the two pins of where it plugs in and see if the voltage kicks up when you first turn it on. (set meter at about 200V AC)
A digital meter may not give an accurate reading because it happens so quick, but it's enough to know if it's kicking ON and then should turn quickly OFF. An analog meter may be more accurate on reading the actual voltage it's putting out.

Someone correct my layman terminology if need be please.......

[shardian]

Interesting. I can handle plugging in a multimeter and getting a reading. Do you have a part # in case it is bad? (G07 monitor)

[Kevin Mullins]

A75414  ..... well, that's what's in the manual. 

Should be something written on it as well.