Color Classic Shaking, shading, and flicker in the game

[KeroXiee74]

Hi, I'm a new subscriber.
I am planning to revive the 5 compact macs that were left in the garage.

First, I repaired SE with Recap. There is no problem with the screen display.

I don't have a hard disk, so I'm trying to make it work.

Even so, I never thought that SCSI hard disks were so expensive today! 8-o

BTW, I would like to ask those who are familiar with Color Classic malfunctions.

The analog of this Color Classic is Recaped. The logic board remains as it is.

The analog board of pots were sprayed with a DeoxIT contact cleaner to make it smooth.
I restored the second one and everything is working fine except for the following symptoms:

With software that uses high-load graphics (such as action games),

the screen shook and the tone was repeated.

And once, the screen went black and didn't come back. * Returned after power off and reboot.

In this case, is the capacitor on the logic board also the cause?

Small capacitors on the logic board are on already ordered and will arrive soon.

Thank you :beige:

 

[techknight]

Did you recap the logic board? its a known issue. 

Also the analog board needs new caps by now as well. Some of them leak, while others dont. Depends on the usage and storage conditions of each unit. 

the logic board, they all leak. 

 

[KeroXiee74]

Hi techknight, Thanks for your prompt reply.

Well, first I read back my first post...Analog recap already done,

Logic's recap capacitors have been ordered and I am currently waiting for them.

I didn't know that the flicker on the logic board occurs,

but I will report it after replacement.

THX :beige:

 

[techknight]

Well the logic board generates the video signal. So if this signal gets distorted in any way, causing sync loss, This can happen. 

But, it can equally still be the analog board, you have to reflow all the solder joints in key areas such as the flyback transformer, the power supply transformer, etc. 

And, the potentiometers are known to get noisy and cause similar issues as well, such as color drift, etc. But you had already mentioned you took care of this. 

 

[KeroXiee74]

Hi techknight,

Oh OK, I will recap logic soon.

I've been aware of the importance of flyback failures on the original iMac a long time ago. I actually repaired a few iMacs.
This time, along board with the recap, other additional soldering was performed and carefully melted.

And yes, all pots have already been cleaned with a contact cleaner and now it works. It seems no issue.

 

[KeroXiee74]

solved! So I'll reply.

I found solder cracks on some Pots for display adjustment.
I thought it was important to inspect while giving a slight shock...LOL

Everything is working well !!! :beige: