Blurry iMac G3 CRT

C3rium1

New Tinkerer
Jan 22, 2024
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Hello, I recently acquired a tray loading Rev. C iMac G3, and it works perfectly fine, but the CRT is a little blurry, especially when I turn up the brightness/contrast in software. I adjusted the physical monitor/focus knobs on the CRT itself and it didn’t help at all. I’m not all that familiar with CRTs. Do I need to recap the main CRT board? Or does something else need to be done to fix the problem?
 

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Nov 1, 2021
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I haven't had to do this myself but from what I read online from some old forum posts, there is a focus and brightness manual adjustment on the back left corner of the imac g3 tray loader. You'd need to take the back shell off but you'd see two adjusters there for the crt. If I can find the time, I'll take the back off mine to have a looksie.
 
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C3rium1

New Tinkerer
Jan 22, 2024
3
2
3
I haven't had to do this myself but from what I read online from some old forum posts, there is a focus and brightness manual adjustment on the back left corner of the imac g3 tray loader. You'd need to take the back shell off but you'd see two adjusters there for the crt. If I can find the time, I'll take the back off mine to have a looksie.
I already made that adjustment myself and it didn’t really help. I am unaware if that’s how it naturally looks, but compared to my 17” studio display for my PMG4, it’s a night and day difference. Makes me think that something is going on. I probably should’ve attached some pictures to my last thread. I’ll update this thread whenever I can get myself to drag my iMac from my closet.
 

C3rium1

New Tinkerer
Jan 22, 2024
3
2
3
I already made that adjustment myself and it didn’t really help. I am unaware if that’s how it naturally looks, but compared to my 17” studio display for my PMG4, it’s a night and day difference. Makes me think that something is going on. I probably should’ve attached some pictures to my last thread. I’ll update this thread whenever I can get myself to drag my iMac from my closet.
I haven't had to do this myself but from what I read online from some old forum posts, there is a focus and brightness manual adjustment on the back left corner of the imac g3 tray loader. You'd need to take the back shell off but you'd see two adjusters there for the crt. If I can find the time, I'll take the back off mine to have a looksie.
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