Abstract: The variable speed gear ratio transmission apparatus of the present invention provides input differential means for dividing an input rotational force into two rotational components, output differential means for combining the divided component rotational forces, input and output shafts geared to the respective differentials, and a variable load inhibitor mechanism coupled to one of the divided rotational components for varying its rotational speed, thereby reciprocally varying the magnitude of the other divided rotational component, with the result of providing an infinite selection of speeds between the operative speed limits of the apparatus.The variable load inhibitor mechanism preferably includes planetary gears connected by brackets, each separately engaging a stationary ring gear, one of which planetary gears is geared to the input divider differential and the other of which is geared to means for determining the load to be placed on the variable load inhibitor mechanism.

Abstract: A circuit permitting an operator to accurately calibrate an instrument to indicate when a variable analog quantity being measured is zero. The analog signal is connected to the input of an operational amplifier which operates in stable mode for large analog inputs and operates in oscillation mode for very small analog inputs. The output of the operational amplifier is compared to zero and when the analog input is greater than zero, the comparator output is a logic zero. When the analog input is less than zero and not in the immediate vicinity of zero, the comparator output is a logic one. When the analog input is very small and less than zero, the operational amplifier operates in oscillation mode as the circuitry connected thereto causes it to oscillate with the duty cycle of the negative portion of the oscillation decreasing as the analog input comes closer to zero. Accordingly, the output of the comparator also oscillates.