Maybe it’s a hand-me-down from an elderly relative. Maybe you found it at a flea market, or it has been hidden in the attic for far too long. It could be an anonymous-looking black box with big dials ...

Elegant wood-encased tube radios that look like antique furniture. Plastic-encased transistors that mimic cigarette packs, Coke bottles, measuring tapes and spray cans of WD-40 along with so many ...