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Please identify this electrolytic capacitor or a replacement.
Posted by: pipkato on 2023-11-09 08:14:54
This tiny 5mm high electrolytic capacitor broke off a 30+ year old MicroMac PerformerPro accelerator card for a Macintosh Plus computer. I’m not an engineer and the only label on the capacitor is the info on the top (see attached image) - 22, 6A, 5G3. The capacitor still has a decent size lead on one side and the remains of the broken off lead on the other side, so I may be able to solder a replacement wire on that side. But I’d prefer to replace the capacitor if possible. I can’t find a schematic for the MicroMac board, and the PCB just has ‘C1’ where the capacitor was. I hope someone can help. Thanks!
Posted by: desertrout on 2023-11-09 08:40:26
22µF, 6.3V
Posted by: 3lectr1cPPC on 2023-11-09 08:44:52
How did you determine the voltage from that?
Posted by: desertrout on 2023-11-09 08:48:45
Documentation somewhere a long time ago... '22' is the capacitance in µF, '6' is the voltage (for some reason always 6.3), the 'S' is the series (I think can be either A or S), then the last line is manufacturer codes I think? Not relevant to the values though.
Posted by: desertrout on 2023-11-09 08:49:54
Had to look it up - apparently cap V's are 6.3 because it accounts for the 25% safety margin over 5V: https://www.eevblog.com/forum/beginners/capacitors-why-6-3v/
Posted by: 3lectr1cPPC on 2023-11-09 08:49:54
Is it always 6.3V? I've run into many that are very clearly labeled as just being 6, while others were marked 6.3.
Usually now they're labelled less clearly though. No harm in going for a higher voltage though of course.
Posted by: desertrout on 2023-11-09 08:56:24
Is it always 6.3V? I've run into many that are very clearly labeled as just being 6, while others were marked 6.3.
Usually now they're labelled less clearly though. No harm in going for a higher voltage though of course.
You can buy 6V caps, but they're super unusual. And not available afaik at this capacitance or form factor.
Posted by: pipkato on 2023-11-09 09:06:14
Thank you all for your responses. I've seen some surface mount equivalents online but not this type. Can anyone offer a link to a replacement, preferably in Ireland or the EU. Thanks!
Posted by: desertrout on 2023-11-09 09:08:08
Thank you all for your responses. I've seen some surface mount equivalents online but not this type. Can anyone offer a link to a replacement, preferably in Ireland or the EU. Thanks!
Do you know the landing size (or footprint) of the cap?
Posted by: pipkato on 2023-11-09 09:26:15
I think I understand. The capacitor is 5mm high so I would guess the footprint is about 2.5mm. There's quite a bit of space where it broke off so fitting an alternative, bigger or smaller, shouldn't be an issue. Thanks!
Posted by: pipkato on 2023-11-09 09:41:00
I found these on Amazon UK. Higher voltage rating but that might be okay. Would these be a decent replacement? https://tinyurl.com/bdfrspn6
Thanks!
Posted by: desertrout on 2023-11-09 09:42:29
I found these on Amazon UK. Higher voltage rating but that might be okay. Would these be a decent replacement? https://tinyurl.com/bdfrspn6
Thanks!
I would say no - far too big, physically. You're looking for something like this: https://www.digikey.ie/en/products/detail/würth-elektronik/865090168010/9836335

Edit: or if you're looking on Amazon, this: https://www.amazon.co.uk/20pcs-electrolytic-capacitor-2-2UF-1000UF/dp/B07VMZJT3H/ref=sr_1_8?crid=274E3VMEL6VG&keywords=22uF+6.3V+electrolytic+capacitors&qid=1699551767&sprefix=22uf+6.3v+electrolytic+capacitors,aps,178&sr=8-8&th=1

But I have no idea of their quality.
Posted by: pipkato on 2023-11-09 09:50:35
Thank you very much for that info. The Amazon ones are SMD - can I just solder some wire leads to them? Sorry, you'll have guessed by now how little I know.
Posted by: desertrout on 2023-11-09 12:07:20
Thank you very much for that info. The Amazon ones are SMD - can I just solder some wire leads to them? Sorry, you'll have guessed by now how little I know.
They have little leads on them already that match up with the pads on the board. There are lots of good vids of how to solder them on - here's the first one I found, shows the general idea:
Posted by: pipkato on 2023-11-09 12:26:10
Thank you. I really appreciate your help with this. Never did anything with SMB components before.
Posted by: desertrout on 2023-11-09 12:40:12
Thank you. I really appreciate your help with this. Never did anything with SMB components before.
No worries! Good luck!
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