If it ain't one thing, it's another...

elekTRONarcade

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So get this....I just finished working in the shed on my TRON board, and voila, it finally lives! I was running through the test screens, checking everything out, and was just about to start filming the few glitches that are present to show everyone here for troubleshooting, when suddenly...

"WHOOOOOSH!"

I look up, and what looks like a huge jet of white steam (not smoke) is escaping through all around the top of the monitor for a few seconds before dissipating. I freak out to Liz screaming for her to unplug it quickly, and we de-ass the area with a quickness. It honestly reminded me of Back to the Future, when the DeLorean comes back through time and is still cold, and they opened the door. Same sound, same look as the steam(?) escaped.

I'm assuming the vacuum tube delaminated or something, and that was air rushing into the void, that made it look like steam.

Not sure what sort of monitor it is, an old WG from a Ms Pac-Man I believe. I got it from Rob a few weeks ago and tonight was the first time I hooked it up. its pretty well toast though.

Just thought I'd share.
 
Update:

So I went back out to the building to grab something, and accidentally stepped on the power switch on the power strip and TRON came back on...and so did the monitor. It actually lit up and appeared fine with the exception of what looked like an extra line of text at the very top, partially cut off. I quickly shut it back down, as I'm not taking any chances.
 
if you got a picture i bet you still have a vacuum, somthing else might have went bad. did you see where the smoke or steam came from? i had a filter cap on my pole position blow and just fill up the garage with smoke and really stank.
 
Sounds like a cap exploded. If it were the flyback transformer, you would not be getting a picture. Although, the sudden woosh and smoke sounds a lot like a G07 flyback burning up... And picture tubes don't spontaneously implode without being hit really, really hard. Did you recap this monitor at some point? Take a look at the chassis, you should be able to figure out where the smoke came from.

-Ian
 
I don't think it was a cap, as it didn't linger like smoke would have, and it didn't have the telltale burnt electronics smell. It was gone within a few seconds.

Imagine putting a lid loosely on top of a boiling pot on the stove, and steam jetting out all around it. That's what it looked like, except from the very top of the monitor along with a WHOOOSH sound. I've never seen anything like it. And even more surprising, the monitor still worked.

I should also mention that it didn't fill the room either. Whatever it was, it was closest to steam. It jetted out about a foot from all sides of the top of the monitor, then was gone just as fast.
 
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My first opinion would be a cap like the other posters they can go bad in a variety of manifestations. A detailed visual inspection is a good place to start. If the chassis is really dirty I would send it through the dishwasher. The next day use a compressor to blow out any moisture under the components and sit it in the sun for couple of days before you power it up. A clean chassis lets you see the problems as well as cleaning the conductive dust and dirt that might have been the problem.

If it still has an image to large for the tube consider horizontal and vertical adjustments.
 
If the monitor lost its vacuum seal it would not work right?

If the tube lost it's vacuum you would not get any kind of picture at all, nor would you get neck glow for more than a second (the filament would burn out when power went through it). You may also get arcing or sparks in the neck.

-Ian
 
Come to think of it, I guess an exploding hydrolytic cap could create this effect, though I'd have figured it would have had some sort of fried electrical smell.
 
An exploding electrolytic will create a plume of steam/smoke. But it'll have a horrible burnt electrolyte smell to it.

We can speculate all day long. We still don't even know what kind of monitor it is. You have to look at it, and see what burned.

-Ian
 
lol No worries Ian, I'm not too worried about troubleshooting it, as I'll probably just recap it for good measure or scrap it completely since it has pretty bad burn-in anyways. Just thought it'd be a semi-amusing story.
 
I'll go with that. Since it was formerly a Ms. Pac monitor, seems legit that one of the ghosts got stuck and escaped. I'm betting it was Pinky.
 
It actually lit up and appeared fine with the exception of what looked like an extra line of text at the very top, partially cut off.

This tells me its probably something on the game board, not the monitor. The monitor wont cause random text to appear but a problem on the game board can.
Caps have a distinct stench to them. If a cap blew you would smell it and the smoke burns your eyes. A smoked IC tends to let out a bunch of smoke but doesnt always smell bad. I would start going over the boards and see if you see anything obvious. Start with the caps and then look over the IC's. Usually when an IC goes you will see a raised spot in the center of the chip.
 
Discovered the monitor is actually a GO7-CBO.

Its definitely a cap Rip....I looked way back onto the board and one of the larger caps is blown. The doubled up text appears to have been fluke, as up top now is a large dark area, and the green s completely missing from the monitor now (as verified by running the screen test). The lack of smoke/smell is weird, but I can say for sure it was a cap now.

I have a new cap kit coming, so no worries. I'll eventually replace this monitor with something newer with less burn and use it for bench repairs instead.
 
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