Hello Spark.
I just received my Spark Core, but I saw one capacitor is soldered only from one side (see attached image, soldered side is brown). So it looks like it detached from PCB. Is it a bug? Should I solder it manually?
Please reply as soon as possible.
Max
For those interested I’m fairly sure this is capacitor C15. Here’s the part’s location in the schematic:
So what should I do with it?
Sorry. I wasn’t answering your question because I don’t know yet. I’m working on it
If you feel comfortable soldering it back on them by all means, go ahead and let us know how it goes!
Note: it’s a polarized capacitor so be mindful of the orientation. Make sure it looks exactly like the picture you posted
Hi Max!
It looks like one of the Cores may have slipped through the solder paste visual inspection stage and did not get solder applied to that one pad up in the corner. Fortunately it’s not going to cripple your Spark Core as it’s just used for extra filtering of the 3V3* output… which is also used A/D reference. It could make your A/D readings less accurate though so it would be a good idea to get it soldered back up. Just be quick and add a bit of solder to the cap with a 750F 30-40W soldering iron and it should be right as rain. If you don’t feel comfortable with that please let us know and we’ll get you a replacement 
Thank you guys! Now I feel comfortable with it and can use is without doubts, so I’ll do all soldering myself, no need for replacement, don’t worry!
Max