Ok, testing has started but someone will have to help me narrow done the problem
- got a fuse for the multimeter so finally can do some testing
- I am aware the power wires on the power board are ass about and have drawn a sketch so will work out if things are crossed over down the line later today but do know that one set of black and red go to the dmd itself and the other set to the dmd board. I know it worked in the past so will not mess around to much at this stage.
- first test: disconnected the leads off the dmd and dmd board and tested voltage at the top rhs test points and the CN5 outlet of the power board with the following results:
* ground / +5v = 4.83 v
* ground / +12v = 11.77 v
- second test: connected power leads to the dmd and dmd board and got the following results:
* ground / +5v = 0.07 v
* ground / +12v = 12.77 v
- third test: with just the dmd power lead disconnected and got the following result:
* ground / +5v = 0.07 v
- fourth test: with the dmd power lead connected and the dmd board power lead disconnected and got the following result:
* ground / +5v = 0.25v
- fifth test: disconnected both power leads and did a machine test as I noticed in the first test the light sequence was on. I pushed start and was able to have a game with flippers etc working.
So from research I know these large dmd's need a good 5v source and with nothing connected it is just under that but when either dmd or dmd board is plugged in, it drops to nothing. I know the game works and the cpu isn't dead (yeah).
Can someone point me in the direction if something has failed on the power board as my gut thinks that but I am definitely no expert with electronics or could it be a bridge rectifier.
Help Please, and explain for a dummie please :)
