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Mac Plus Analog board C1 capacitor polarity
Posted by: joshc on 2020-02-12 00:46:24
I have a Plus analog board (International version) with a C1 cap that needed replacment. I ordered a replacement, which is polarised - the original was not.

So... the ultimate daft question, which way should it go? I've tried to source images of other analog boards but can never tell...

Here's what I think is right...

IMG_8526.jpg
Posted by: LaPorta on 2020-02-12 03:00:41
Unfortunately, you can't do that. C1 is non polarized because it has to be: the current will quickly pass from one direction to the other. At best, this won't work. At worst, the cap will explode.

Here instead is a suitable replacement: https://www.mouser.com/ProductDetail/667-ECQ-E1395JFW
Posted by: joshc on 2020-02-12 04:21:16
Unfortunately, you can't do that. C1 is non polarized because it has to be: the current will quickly pass from one direction to the other. At best, this won't work. At worst, the cap will explode.

Here instead is a suitable replacement: https://www.mouser.com/ProductDetail/667-ECQ-E1395JFW
That explains why I couldn't find a photo with a polarised cap there and this now makes total sense, I did already start to wonder...

Oh well, maybe one day I will find a use for those caps (I have 10 of them).

Thanks for the tip!
Posted by: joshc on 2020-02-12 04:29:34
Unfortunately, you can't do that. C1 is non polarized because it has to be: the current will quickly pass from one direction to the other. At best, this won't work. At worst, the cap will explode.

Here instead is a suitable replacement: https://www.mouser.com/ProductDetail/667-ECQ-E1395JFW
Sorry, I'm not great with electronics - would this also be suitable? https://uk.rs-online.com/web/p/polypropylene-film-capacitors/7270048/

(shipping cost too high for me from Mouser)
Posted by: LaPorta on 2020-02-12 06:59:52
I believe Mouser has a European site, if I am not mistaken...

That, too, appears suitable.
Posted by: joshc on 2020-02-12 09:18:42
@LaPorta Thanks for your help with this!
Posted by: LaPorta on 2020-02-12 10:43:43
No problem! Please, let us know how it all works out, and show us the finished product.
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