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PS/2 Floppy Drive Caps - Un polarized?

Well, you might have to settle for radial leaded aluminums, say, Nichicon USP1C4RYMDD. Dimensions are 4mm diameter, 7mm height. Or you could see if there's an SMT MLCC that fits the pad spacing.
 
If I were designing this drive today, I'd use an MLCC. Inherently non-polar, better tolerance, smaller package, wider temperature range and much longer lifetime (no wet stuff inside to dry out), lower ESR...

If an 0805 SMD package will work, here's your baby.
 
Thanks very much for the fine recommendations.
I had done some google due diligence and stepped through all the np options I could find on ebay.
I wasn't sure that the MLCC would have similar characteristics and didn't look deeply into those.
I sure hope that the caps are the problem with the drives...
 
Follow up on this for posterity.
Summary: Two failed PS2 1.44 drives, one from a IBM P75, the other from an P70.
I theorized that caps were the problem, as there was clear evidence of the leaked canned caps and some
corrosion on the circuit boards.
I bought and scrounged caps to replace them with. I destroyed a pad on each drive but managed to
route to the destination point of the traces.
Working with two soldering irons helped make the removal easier.
I bought some aluminum can caps similar to the originals but found that working with leaded parts
was much much easier.
The bottom line is the P70 drive did not respond, but the P75 drive did.
Unfortunately, the P75 is dead, so the good drive went into the working P70.
Here's the photos, the caps installed in the fixed drive is in photo #5.
http://imgur.com/a/GneNM
So it is possible that failed PS2 floppy drives can be fixed simply with new caps-
maybe not all of them, but this is evidence that some can.
Next it on the list is a IBM Convertible with at least one non working drive.
Hopefully I will succeed there too.
 
Yeah it is a thrill. I had my doubts when the repair of #1 didn't work.
In fact when I first booted up with #2, it booted off the floppy- my eyes were wide with surprise. :)
I didn't hold much hope for #2 but I'm stuck to my guns that it should be the caps and that's all.
My guess is that #1 had a further trace problem either from my work or corrosion.
 
Depends on what part of the circuit these capacitors are used in. Since there are 3 grouped together like this, that tells me its part of the 3-phase BLDC signalling to the coils. MLCCs are nice, BUT they do have an inherent problem! the capacitance changes based on voltage applied to it. In most cases it may not be critical, but there are some cases that problem could result in malfunction.

If it works, great. But keep this in mind when using ceramics to replace 'lytics.
 
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