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N_Cook N_Cook is offline
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Default video projector, lamp or high power ps problem ?

Hitachi CP X327, 3xLCD & discharge lamp, unusually the full component
level sm is out there.
As the lamp repeatedly strikes across giving short bursts of preliminary
greenish light, the 5KV or so striking supply must work and also I
assume some voltage from the main sustain, high power lamp ps, until the
unit goes into protect mode.
Initially I intend jury-rigging across (with added insulation) another
known good lamp to see if a lamp problem. The lamp looks visibly fine,
no cracks/crazes in the glass and no blacking in the active bulb area.
Monitoring the mains supply current, usual surge for the low power ps
coming on but only a hint of a surge for the high power ps coming on.
I've previously had a projector where all that was wrong was the mains
switch had arc-pitted contacts and could not supply the current for the
lamp ps and so similar mains current symptom. I'll check that and check
the internal cabling connectors, but what else to check, assuming it is
a ps issue after the fudged lamp test also fails to light.