(Phys.org)—Although vacuum tubes were the basic components of early electronic devices, by the 1970s they were almost entirely replaced by semiconductor transistors. But in the past few years, ...

There are no microcontrollers in this project. In fact you wont find a single transistor. This classic regenerative tube radio, modeled after an early 20th century homebrew is complete with schematic ...

Linear, small-signal AC models can be useful in the analysis and design of vacuum-tube-based circuits. Under large-signal conditions, nonlinear models are typically required. Almost 120 years ago, ...