Amplifying With Vacuum Tubes: Circuit Design Guide for the Novice

Vacuum tube fundamental circuit design written for the novice interested in vacuum tube amplifier construction. A brief concise book covering several factors of circuit design including bias requirements, voltage gain requirements and power supply requirements. To help understand circuit operation rather than use traditional schematic drawings pictorial illustrations are used. In several sections circuit operation is demonstrated using illustrations along with a vacuum tube breadboard. Experiments are used to correlate circuit design to actual working circuits. Circuit calculations involving fundamental electronic formulas can be performed using a standard twelve digit calculator with a square root key. Examples of how to solve calculations are provided. Basic electronic knowledge of voltage, current and ohms law related to vacuum tube circuit design is included where appropriate. Output transformer matching principles include plate resistance, load resistance, inductive reactance, impedance and the effects of frequency on impedance and output loading. Determining plate resistance of output tubes in parallel operation includes examples of operational circuits and process of measurements. There are 90 pages of circuit design containing enough information to design high quality vacuum tube amplifier circuits. The last few pages of the book have related information including the use of sound pressure levels to determine amplifier power requirements. Main focus in this book is Class A operation. Push-pull is briefly covered. Output transformer and parallel output tube operation experiments demonstrate characteristics of Class A output matching. Output matching formulas used in the text are a bit more complex, but can be calculated on a standard twelve digit calculator that includes square root function. Examples are provided.