One game causing interference bands on others?

jkoolpe

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Hey all!

Anyone have any ideas on this: I have noticed that whenever I have my Food Fight on, it seems to cause a minor horizontal interference "wave" to travel through (bottom to top) the other game monitors in other cabinets that are physically near FF. When I turn off FF, the other monitors are fine.

I have a G07 in the FF that's been capped a few years back...the other monitors being affected are different types, and even a brand new one in one of these games.

Any ideas on what might cause this?

Thanks,

Jon
 
It could be the monitor or the board actually, check the board for hot chips, and by hot I mean stinking hot, burn your finger hot.

Especially the amp chip, but also the YM chips in the audio section. I have seen this with both an amp chip that is oscillating and also a YM chip that was on its way out, both were working as far as putting out the correct audio but they were causing screen issues.

If the amp chip is bloody hot then the cause is likely to be a bad capacitor between the 12V rail and ground, usually it is the physically largest capacitor on the board, probably a 16V cap of several thousand uF, there is also usually a small polyester cap in parallel with it, together they smooth the 12V line and mop up any noise on the line that can cause the amp to oscillate. If they are bad, or have been knocked off the board then they can cause this. Once the is sorted the amp will run warm an happy again.

The YM option is probably insanely unlikely, I have seen it once tho, if one is getting too hot to touch then your only option is to remove it and replace it with a good one.
 
It's easy enough to "divide and conquer" - just disconnect the power to the monitor in Food Fight, and see if it still interferes with the other games. if it does... then it's not the monitor. :)

It could be any number of things creating interference. It can be hard to track. Are the affected games all on the same circuit/power strip? Could even be some kind of electrical problem - ground leakage or something. Again, easy enough to test - leave the game where it is, plug it in to an extension cord, and plug the game into another circuit.

-Ian
 
Thanks guys...

It does appear to be coming from the FF G07 monitor...I tried unplugging the monitor and the interference band was no longer present in the adjacent games' monitors, but when I plugged it back in and fired up FF again, it came back.

Any idea why this monitor does this and not my other G07s? It's not a major thing, but it is annoying...

Jonathan
 
Oh yeah...and when I moved the game away just a foot or two from the other games, the problem also went away so it does have to do with proximity.

Not all of the affected games are plugged into the same circuit breaker either...some are, others are not.

Jon
 
Something is probably oscillating... Is the width coil in the G07 cracked/broken? Do you have the original flyback? Is it properly grounded?

-Ian
 
The monitor has a new flyback that I installed at the same time I did the cap kit...probably about 3 or 4 years ago at this point. The ground wires appear to be well-connected and good.

I'll pull the deflection board when I have a chance and see if anything looks funky...

Jonathan
 
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