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IICX Vulnerable Spots?

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I've had a box of 20 or so IIcx logic boards in the attic for a decade or more. I got the batteries out of them early on, so I never had a battery explosions, but I've been contemplating the damage leaking capacitors will do over time, and thinking I really need to get the box down and pull all the caps.

 

So, I'm in the process of doing that now.  It's a slowish process.   I don't have time to actually test and "repair" each board, but I want to halt any damage.  

 

After I pull the caps, I'll thoroughly clean the boards.    Now, here's the question:  Is there any particularly vulnerable spot on the IIcx where capacitor goo collects and causes damage?    In other words, anywhere I should apply extra attention while applying the solvents and cleaning?   I would hate to remove the caps, clean the boards, and leave corrosive goo hiding under some chips eating away traces.

 

The 74 series chips around the battery holder and the Right Sound Chip look like likely candidates.   At least, on most of these boards, their pins have a fair bit of corrosion.

 

I think these boards were originally part of Shreve Systems collection of old boards.  One of them had a note on it dated '96 saying it wouldn't work.  I bet the caps had failed back in '96.  My IIci needed new caps by '97.  

 

Many of these boards have no ROM chips.   Does the IIcx typically have them soldered down?  If so, then why in the world did someone remove the ROM chips from so many of these boards?  It's not like you can put them on a SIMM.  The logic board ROMs are too large.

 

Then there's a few boards on which the traces have pulled up like a bunch of little hairs.   But I guess the custom chips will be useful for other repairs..

 

Do I remember reading somewhere that the sound chips are actually a D to A converter available under a regular non-Apple part number?   

 

I got one of the Quadra 840AV boards down while I was at it.  This one had a note I made from 2007 saying it was working.   I hope it still does.  There's a lot of visible leakage around the caps now.  I need to find the other one, which is actually in an 840AV case and remove its caps too.

 

Geeze.  I thought I was doing good to remove the batteries.  I could spend a lot time removing all the SM electrolytic caps from logic boards in the attic.

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Washing the boards in water it's in my opinion a really good start, but probably giving those board a new home will be the better way to keep those going... just my opinion.

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Are you planning on using or selling them anytime soon? Remove the aluminum electrolytics and wash all the boards with soap and water, let dry, and store. No real reason to do the recap until you actually need to use one and after all the prep work soldering a few caps would be easy. I recap my boards as needed and store them in a cool dry place so they don't leak but I don't have more then a couple spare boards around (Mac IIx, IIcx, IIci come to mind).

 

If it was me I would probably find a better place then a freezing or boiling attic to store the boards. Fluctuating heat and humidity is hell on electronics.

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Are you planning on using or selling them anytime soon? Remove the aluminum electrolytics and wash all the boards with soap and water, let dry, and store. No real reason to do the recap until you actually need to use one and after all the prep work soldering a few caps would be easy. I recap my boards as needed and store them in a cool dry place so they don't leak but I don't have more then a couple spare boards around (Mac IIx, IIcx, IIci come to mind).

 

If it was me I would probably find a better place then a freezing or boiling attic to store the boards. Fluctuating heat and humidity is hell on electronics.

Yes, it's not good, but it's what I have. In this part of Texas they don't build basements for some reason and this house is from 69/70 when closets were still an afterthought.

 

Originally, I was planning to clone the Outbound SCSI adapter for which I would need some 53c80 chips and at the time didn't know of a source. At about the same time a member of the Mac community offered to trade me for something I had (don't remember what) and he had access to a friend's or acquaintance's trailers of Mac detritus, I think he said from the Shreve auction. Apparently they did so many IIcx and IIci to Quadra conversions that they had pallets of old logic boards. Anyway, I asked for some boards from which I could scavenge the SCSI chip and that's how I got this box.

 

I don't really want to put time into it right now, but figure if I don't I'll just have a box of goo left, plus I needed to dig out the Q840AV boards too. The capacitors are just like exploding batteries, only slower. Sigh.

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