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View Full Version : Apple Performa 200 has vertical lines



wgreenhalgh
December 2nd, 2009, 06:22 PM
I am trying to bring a Performa 200/M4150/Macintosh classic ii back to life. http://208.112.81.25/lines.jpg Turning it on results in vertical lines on the display and it does not get to the POST sound. I have followed the steps on this repair document (preterhuman.net/texts/computing/Apple_Service_PDF/68k_Macintosh/classic_ii.performa_200.pdf). The conclusion in the repair document is the revision b Power/Sweep Board needs to be replaced. I would like to single out a single bad component via a schematic or see if someone has any experience with this issue that could suggest other possible causes.

Anonymous Freak
December 2nd, 2009, 08:01 PM
I don't know too much about those type of problems, but you might want to ask the people at 68k MLA (http://68kmla.net/forums/).

channelmaniac
December 2nd, 2009, 08:47 PM
Resolder the connectors on the power/sweep board and try it again. I'm not sure how the heck Apple did it, but all the ones I've ever seen were soldered under some kind on tension. They would make crackling sounds as the solder heated and the pins would pop to release the tension.

Druid6900
December 2nd, 2009, 09:17 PM
It looks like the same setup as the 128, and the main video problem was that the video board was mounted vertically.

Over the years, the heat up/cool down cycle and gravity cracks the solder joints on the flyback and a large "sand-block" power resistor.

I've found that desoldering and resoldering the flyback and that large resistor fixes most of the problems.

channelmaniac
December 2nd, 2009, 09:32 PM
Wait a sec... My suggestion was for the Color Classic.

The B&W version? Is there a 74xx logic chip on the power/sweep board? If so, replace it. It's bad. I don't remember if there's one on that board like the old SE and SE/30.

RJ

MikeS
December 3rd, 2009, 12:25 AM
Don't know if it applies to yours, but googling 'simasimac' might give you some ideas.

Seems that a lot of Apples & Commodores are beginning to suffer from leaky caps lately.

Starshadow
December 4th, 2009, 06:42 PM
That seems to be a problem common with the Classic line ( Classic and Classic II). I found that the tin can caps around the sound chip area on the motherboard will leak if the Mac is in storage without a climate control. Sometimes just leaving them on for a while in their zonked state will cause them to come on eventually, or they'll come one if you switch it off and back one.