Fed up with tangled earbud cables? The Loop is an incredibly simple solution that keeps your headphones neatly wrapped and protected even while they’re in your pocket, purse, or backpack. I don’t know ...

Spoiler summary: The loop inductance of a circular loop is about 25nH per inch of circumference. Remember: before you start using rules of thumb, be sure to read the Rule of Thumb #0: Use rules of ...