Analog Multipliers and Squarers Using a Multigrid Modulator

This article describes the use of a multigrid vacuum tube as an AM multigrid modulator multiplier. The accuracy of the multiplier is dependent only upon the linear properties of the vacuum tube used and not upon careful adjustment of the operating potentials. It is unusual that such a simple device should give a range of 78 db with only a ±2 per cent full scale error. The advantages and also restrictions of this device along with a complete range of dynamic performance are included in this article.