If your first thought is that he must have made a flyback converter to step that voltage up to something more useful then you’re in for a surprise, because the single 6J6 pentode really does run ...

A direct-conversion radio receiver required an audiogain of 450 from a pentode vacuum tube. A pentodehas a high transconductance—that is, the ratio of thechange in plate current to the change of the ...

What you're looking at is the Audio Research Reference 330M power amp, a fully balanced, pentode-mode monoblock ... stands for Junction Field-Effect Transistor, a semiconductor device that uses ...