Sorry if this is not the right forum for the question, but the end result of what I must do is close enough to a hardware hack.
I have a 14" Apple Display. It works, but the problem is that the picture is too wide (by about a full half inch) for the screen and the picture (top to bottom) is too small (as in only 3" tall). I cracked open the case and adjusted the pots for the H and V. Horizontal will not adjust to any helpful degree. Vertical adjusts beautifully, BUT the longer the CRT is on, the taller the picture grows. I used to know what this meant in terms of resistors and caps for whatever needed replacing - I obviously no longer recall.
Can any one help me determine what the problem is?
Also, the picture periodically has a "wave" as the color tone flutters. Most likely another problem due to age and high use, but fixable for the patient with half a clue.
I did something similair and found out that the symtoms you described is because the control board is bad. The screen getting wider/taller is because the board is not able to keep the tube at a steady charge.
Ahh, that is a capacitor problem. I know that as they age, and go through heavy use, they get tired. I have a plethora of parts to pull from if need be, but I need to be able to isolate the path. I just do not want to drag out my o-scope as it is a pain to get my bench set up for that kind of work.
Yeah, this bad boy is wanting to die. The tube itself is good, as is the plastics, but the rest of the unit is pretty much hosed.
Conclusion: I need to buy a boat as I already have a suitable anchor on hand.