No matter where you purchase your solder from, beit in Europe or the USA, you need to purchase a good quality Eutectic Alloy solder (63:37). There are several brands available almost everywhere: Kester, Multicore, Cardas, Alpha and others. For even better conductivity consider the silver alloy version (62:36:2) of these brands. It’s a bit more expensive, but it works super well. Yoou might try looking on eBay; they’ve got a LOT of different types, but do stick with the Eutectic alloy. If you’re not familiar with that term, it’s the solder alloy that has almost no “plastic” point; it goes from liquid to solid in a very tight window – within a couple degrees below it’s melting point it becomes fully solid, unlike other alloys like 60:40. Hope this helps!
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