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The game was working properly during pre-show testing but whilst making a small tweak to the picture I discovered that the HV focus bleeder was leaking and HV was arcing to ground. The chassis was removed for repair.
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I had no spare bleeders left and began looking for replacements. The manual listed what looked like the bleeder as Hantarex part code 38000000 described as "cavetto split blider 167M" that translated as "cable split blider" where "blider" was untranslated, possibly a typeo. Was 167M the resistance of the split?
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The bleeder was a very high resistance tapping off a few thousand volts from a 20KV
anode with low current. The plan was to use the highest convenient voltage source,
a 240VAC isolated step up, that was to hand. The base measurements were:
Using current measurement read 0.6uA consistent with current calculated above and corresponding to approximately 400MOhm. This was a very approximate calculation and didn't match the implied value of 167MOhm from the manual. Further, the few remaining companies that sell NOS bleeders don't list their resistance to identify a replacement. I ordered a selection of physically identical bleeders to compare against.
Previously I had replaced a failed bleeder to fix a focus issue. At that time, I'd used a HV probe to measure the focus voltage, finding it very high and drifting. I'd kept that failed bleeder and applied the same measurements as above. The current measurement was 4.1uA equivalent to 58.6MOhm and voltage measurement 34.52V equivalent to 61.1MOhm. The results were consistent with the observed failure.
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The NOS bleeders would not arrive in time for the show so one was fitted from a spare chassis and the chassis ran on the bench with no issues.
Subsequently the Zaxxon bleeder also failed and investigation on the bleeder is continued on the Zaxxon Maintenance 2022 page.