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Another SE/30... Y1 resistor (?)

Y1 something? Sorry, but you have a bad case of a battery leakage. You definitely should clean this board AASP and then look for damaged components. Also the picture is too blurred to be any good.
If the board is not too damaged, you can then proceed with recap. Clean the board first with soapy water and then with isopropyl alcohol a few times.

I hope that you'll be able to get it running, but this picture doesn't look too promising.

 
Yes... of these things I am aware.  Y1 is the little space just below the rightmost part of the battery holder.  [



Once I clean the board completely (and also parts of the metal on the case, and the logic board shield) I will still need to replace whatever Y1 is.

And to that effect... never mind; apologize for the apparent repost.

https://68kmla.org/forums/index.php?/topic/13231-help-my-se30s-battery-exploded-and-so-did-c12-an-y1/

 
Oh man, that looks horrible. I wonder if replacing Y1 will help...

Anyway, Y1 is an oscillator (piezoelectrical crystal) with a frequency of 32.768 kHz. Normally it looks like this:

Mac SE 30 Y1.jpg

 
I mean I'm not an expert so it may be catastrophic but it doesn't look worse than some of the rebuild efforts(' before pics) that I've seen.  There is minor corrosion elsewhere.  I bought it as an engineering/learning project.

[thanks, by the way, bobo]

 
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yup wash it , maybe remove that battery holder too.

then you can get more of a complete idea as to the extent of the dammage.

After you do all that take a high resolution, well lit image, and we can maybe give you some more input as well.

 
What do you suggest?  Denatured alcohol/methylated spirits?  I've only so far been wiping up with paper towels and qtips.  I won't have time for a major effort a few days.

 
While there are probably better removal liquids, I am a big fan of vinegar. Its cheap and you can get it anywhere. And it sits on the boards for a long time (does not flash off). It does not do a great job at some of the hard stains from the acid, but it removes corrosion very well. Such as the green stuff on chipset legs, etc. Odds are you already have some, so its worth using as a first shot. A soak at 30 minutes will help with most. Rinse well.

 
I don't know what vinegar you're in the habit of using but white wine vinegar (mostly with a toothbrush) was very effective for a lot of the corrosion - within minutes, and the minor corrosion on some of the RAM within seconds.

I also noticed weird, minor burnt-looking marks around some of the holes in the small RAM SIMMs. I don't know if it's clear in the picture.

Sadly I broke off C12 and pad. Otherwise, I'm going to test it with all the other original components, I think. The analog board looks good as does the CRT. I powered it on without the logic board and everything sounded fine

 
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I put some on heavily and let it soak then I too use a tooth brush to scrub and clean. I do this around all caps as well. You will want to rinse well, vinegar is acidic. So I use warm water, a few drops of dish soap and a paint brush to scrub the entire board. You will want to remove socketed chips (photograph first). Then I use a hair dryer for initial water removal followed by a space heater to dry completely. I occasionally blow into the ports/PDS slot to get any water out then back in front of the heater. If you have hard water, you will have to use distilled water for rinsing instead. This is my method, there are others of course.

 
There is some corrosion under SIM 1 and some more persistent corrosion elsewhere that I'm going to leave for the night.  Then I'm going to use rubbing alcohol for the acid (unless you/anyone has better ideas) - I'll probably need to desolder the battery tray.  I've been waiting on $0.99 solder from China for a few months.  I'll take more pictures tomorrow.

 
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If you turn the computer on without the logic board, should the CRT jump to life? And should it normally be grounded to the chassis for discharge?

 
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CRT should not illuminate. Discharge to chassis is fine, its about balancing out the electrons. The SE/30 should automatically discharge in a minute via a resistor. But its always possible its not doing so given its age.

 
Good. There's minor ghosting I hadn't noticed

Can I pop an original SE logic board in sans floppy? To test?

 
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I'll post pictures of the RAM and logic board later when I work on the acid a bit. The analog board, CRT, floppy, and at least the leftmost ADB port work fine. The HD spins. Either it's wiped or dead.

 
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