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The game made it through setup but failed with no picture part way through show day 1. A spare MTC-900E/USA chassis was fitted that got it going again. Part way through show day 3, the last day, the picture developed vertical roll and was turned off until closing.
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A cabinet fan was fitted following the same design as was used on Money Money - a low power 12V fan connected to the unused -12V output from the IGR power supply.
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Testing on the bench, the chassis had no vertical sync that was corrected with a small pot tweak. It may have drifted slightly as it warmed up during its debut at the show.
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I didn't notice at the show that the LOPT had failed and swelled up like a balloon. This LOPT was only fitted a few years ago so I was suspicious that the LOPT failure was a symptom of something else. The blown LOPT was removed.
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A light bulb dummy load was attached across the primary coil pins and the chassis powered on. The 115VDC measured 138.9VDC and the adjustment pot RV12 had no effect on the voltage. Working through testing the transistors in the power supply regulation circuit found:
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The replacement LOPT looked somewhat low quality with misaligned pins (a recent repro). A paper template was made from the old LOPT to allow the pins to be aligned more easily and the new LOPT was fitted. The chassis ran OK on the bench with 115.3VDC measured at the power supply. After adjusting the new LOPTs screen & focus the picture quality looked good on the bench.
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Retesting the chassis back in the cabinet found no issues and excellent picture quality.