neon is good - check
transformer works - check
neon fires when grounded so not a continuity/grounding problem - check.
Then the problem most likely lies upstream on the board - specifically the 2 chips that regulate the light saber.
Main culprit - ULN2803A at U35 on the power driver board
Accomplice - 74HCT574 at U34 on same.
bugger. BTW is there any way of testing these chips or is it just a matter of replace and see if one or both fix the problem? Also is there a common reason why these go that must be addressed or I'll just keep blowing these guys? Thanks
