But there’s an earlier amplifier technology that used a solid state circuit which is largely forgotten, and [AWA Communication Technologies Museum] has featured it in a new video. We’re ...

Despite the oldest solid state audio circuitry now qualifying ... For the electronics enthusiast a tube audio amplifier makes for an interesting and unusual project, and for that reason it ...

Kelly suspected that solid state science might provide a new kind of amplifier to replace the vacuum tube in AT&T's phone system. The tubes amplified voice signals as they traveled through the ...

Amplifiers that use vacuum tubes instead of – or alongside – solid-state electronics are marketed on the basis of their ...