This is a noncommercial site operated by Max Robinson and dedicated to passing on and preserving knowledge of vacuum tube circuits and techniques. Keep the electrons flowing and the tubes glowing.

The circuit was designed to create a line preamplifier by acquiring the use of double triode tubes. The circuit comprises of three parts, the main preamplifier circuit with tubes, the input selector ...

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, ...