Vertical Line of "Dead Pixels"

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Vertical Line of "Dead Pixels"

I need some advice on an  issue of an apple II europlus

It has a vertical row of dead pixels on the screen (see picture).

It happens regardless of which screen i use (i have  old monocrome monitors here and my current tv also still has a component in)

And the screen in the picture works fine when i connect it to my dads ITT Apple II

So it has something to do with the device itself. Any guess what causes an apple II output to be almost good?

PS.: it has a german character rom installed that's why  ] is replaced by Ü und [ is replaced by Ä

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That's not a row of dead

That's not a column of dead pixels. Turn down the brightness on your monitor (you shouldn't see any green background) and all will be good.

 

By having the brightness set so high you are seeing stuff outside the normal Apple II display "window." That is, blanking stuff. The window is purposely set to underscan - that is show contents using less than the full display screen - to avoid issues with focus, linearity, and convergence (color screens) that would have made it hard to use with the TV/monitors of the day.

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Thanks for your answer

Thanks for your answer

So this line is to be expected? because the itt doesn't have this line, that's was what made me question it in the first place

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jeffmazur wrote:That's not a
Matombo wrote:

Thanks for your answer

So this line is to be expected? because the itt doesn't have this line, that's was what made me question it in the first place

 

Do you recall how I said elsewhere that developing separately for the behaviour of the ITT, the Europlus and the NTSC ][+ was a logistical nightmare?

 

Each of the three have entirely different video circuitry. The ITT and the Europlus each have their own unique implementation of 'PAL-compatible' signals, and as I recall the ITT can't do colour burst at all. I may wrongly remember that; and it could just have been a bit odd. You will eventually want one monitor for each. The 'European NTSC', 50Hz Monitor //c is the best option IMO, if you don't want colour.

 

If you want colour, that is an entirely different matter, and no, you cannot derive proper colour using an LCD here. 

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