shawn@oscsunb.osc.edu (Shawn Ryan (ST)) (01/12/90)
Just as my Mac Plus reached it's 1 year anniversary, it died. Whenever I turn it on, the screen stays black but a faint outline of the empty disc icon can be seen. When the system disk is inserted, it boots up but the screen is still very pretty much black. faint outlines of the disk icons can be seen on the desktop and it will boot up programs (if you are able to find the icons with the pointer). I called places all over columbus ohio and recieved awnsers ranging from analog board, power circuts, bad screen, and bad rom chips. does anybody know of a remedy (or the problem for that matter). Thanks Shawn Ryan Ohio Supercomputer Center. reply to shawn@osc.edu (forgive the spelling im in a hurry)
cyamamot@aludra.usc.edu (Cliff Yamamoto) (01/12/90)
In article <443@oscsuna.osc.edu> shawn@oscsunb.osc.edu (Shawn Ryan (ST)) writes: >Just as my Mac Plus reached it's 1 year anniversary, it died. >Whenever I turn it on, the screen stays black but a faint outline of >the empty disc icon can be seen. When the system disk is inserted, it boots up >but the screen is still very pretty much black. faint outlines of the disk >icons can be seen on the desktop and it will boot up programs (if you are able >to find the icons with the pointer). > >I called places all over columbus ohio and recieved awnsers ranging from >analog board, power circuts, bad screen, and bad rom chips. does anybody >know of a remedy (or the problem for that matter). The Mac is like a TV. At least you can see the outlines. This means all your vertical and horizontal circuitry is working. I would have to say the High Voltage is down or the picture tube is bad (these are worst cases). *But* what you can do is check the trim pots (potentiometers) on the left side of the Mac. I believe there is a trimmer for adjusting the brightness limit. From what you describe, it sounds like the brightness is all the way down and the contrast is the only thing that allows you to see outlines. Get some contact cleaner and spray some on the contrast and brightness trim pots. Then move the adjustments a bit to move the wiper around. If that doesn't work, turn the power off and jiggle the socket on the picture tube neck and check for any corrosion buildup. If all else fails, suspect a bad analog board. Cliff