Sick Laser

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evank's picture
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Joined: Jan 29 2005 - 22:33
Posts: 54
Sick Laser

Laser 128 stopped making the start-up beep (nor does its FDD activate) and the screen looks like this: http://vcfed.org/evan/laser/screen.jpg

Ideas?

evank's picture
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Last seen: 9 months 11 hours ago
Joined: Jan 29 2005 - 22:33
Posts: 54
Re: Sick Laser

Swapped its 6502 into my //e. The //e boots fine. So it's not the processor.

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Re: Sick Laser

Talking to myself here Smile ...

I put it back together. Only one extra screw (seriously).

Now it works.

All I did was remove and reinsert the processor.

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Last seen: 1 year 8 months ago
Joined: Aug 28 2019 - 08:51
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I scored a 128 today with the

I scored a 128 today with the same issue.  Confirming voltages from the supply right now.  May have to try your processor trick if I don't find anything with the power supply.  

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Last seen: 11 hours 53 min ago
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Oxidation on the chip legs

Oxidation on the chip legs causes it to lose contact. Reseating the chip solves that. On the Laser there's only a couple of socketed chips, when there's an issue with a II+ the first thing I do is reseat the chips. Unfortunately there's a lot of them and you have to remove the top case.

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I reseated the ROMs as those

I reseated the ROMs as those were the only two chips not soldered to the board.  Didn't seem to work.  Getting random characters on the screen at startup.   The power supply checks out, getting all the proper voltages.  Going to start checking traces and voltages at the other logic chips. 

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