Quote:
Originally Posted by jpdylon
You see this symptom in solid state sets more than tube. The cathode gets weak, reducing brightness. So the user cranks up the contrast and brightness a little. The smear to the right I believe is actually caused by the driver transistors on the CRT board going into saturation - but I don't remember for sure. More of a tube guy than SS. Never seen this symptom on a tube chassis yet.
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Yes, output transistor saturated by overdriving it. When a transistor is driven into saturation, it also stores charge that has to be pulled out before it can be turned off again - hence the delayed transition.
Could be weak picture tube or just a design that doesn't limit the drive levels to prevent this. You could try adjusting the cutoff (G2) voltage, may find a compromise of G2 and brightness control. Or just turn the contrast down some.