Frequency Doubling in a Triode Vacuum Tube Circuit

This paper gives a quantitative analysis of operating performance of a triode vacuum tube as a frequency doubler. With slight changes this analysis can be applied to tripling, quadrupling, etc. Three methods of attack have been outlined: theoretical analysis, graphical solution, and experimental results. The theoretical analysis furnishes a general solution to the problem, from which general conclusions as to the best operating conditions can be drawn. The graphical solution furnishes a simple method by which rapid calculations can be made for a particular case. The experimental results are valuable for comparison because they give the actual results of operation. The primary object of this work has been to investigate the conditions that will give maximum plate efficiency and consequently the most desirable operating conditions, also keeping in mind that power output and power amplification are important factors to consider in the practical application of the frequency doubler.