Macintosh 128K screen trebling

[juanmas]

Hi there!

I’ve turned on my 128k and noticed that the screen is trebling. I get dizzy looking at the screen. I think it could happens by the fly back capacitor but not sure. None capacitor has been replaced.

Any idea?

 

[juanmas]

Ok,

I left the Macintosh on for a hour but the trembling remains. So I’m not sure it could be a Capacitors issue. The screen is trembling with the maximum brightness or with normal brightness. I doesn`t goes worst using the floppy disk.

Someone can help?

 

[Johnnya101]

I suppose it could be a bad ground. That would be easiest to check. Remove the case and locate the ground wire and bolt, and tighten it. See if that makes a difference.

Is it possible to get a video? Would help a lot.

 

[jack]

Try re-soldering the yoke plug on the A/B... that is, completely remove the old solder and add new.

You could also try re-soldering the flyback while you are in there. Those are the first two things I would check before capacitors, etc.

 

[juanmas]

Ok it’s weird,

I’ve took the Macintosh apart and left it at the floor because I need the table. Now I’ve took it again back to the table and now the screen is perfect!!

It’s possible the ground wire as Jhonnya101 said.



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