What vintage technology site would be complete without at least one vacuum tube project! My college engineering experience was during the 1990s and I never got the chance to learn about vacuum tubes or punch cards, or even Pascal for that matter (first years had already switched to C++). Tubes (or valves if you’re British) have been driving electronics since the early 1900s and they’re still used today for high end audio and certain RF applications. They are a wonderfully robust technology, provide unparalleled audio quality compared to most transistor-based designs and they are simply beautiful to behold. I felt