Applying Zener diodes to expanded-scale instruments

ONE INTERESTING RESULT of the application of information theory to electrical measurements is that design practice should change in some particulars to keep pace with application needs. This applies with particular force to the span of measurement which, in many instances, is some normal value plus or minus the expected variations in the voltage, current or power in the circuit. In contrast to this need, the span of most electric instruments traditionally starts at zero and extends to some value in excess of the anticipated maximum. The accuracy and visual resolution of measurement may be increased by scale designs which transfer the little-used lower portions of the scale range to the estimated range of operating values.