Further Extensions of the Theory of Multi-Electrode Vacuum Tube Circuits

HE response in multi-electrode vacuum tube circuits due to impressed electromotive forces has been the subject of several papers. For the three-electrode v a c u u m tube circuit J. R. Carson 1 has used a method of successive approximations, assuming constant amplification factor and no conductive grid current. E. Peterson and H. P. Evans 2 removed the restriction on the amplification factor b u t maintained the assumption regarding the grid current, while F. B. Llewellyn 3 considered the general case with both plate and grid currents. Finally, J. G. Brainerd 4 has treated the general case of the four-electrode tube circuit. The theories given by these authors did not take into account any feedback between the circuits of the electrodes except in the first approximation.