By assigning analog voltages to the coordinates of a graph, drawings can be electrically displayed. By means of a sine-cosine potentiometer, resistance chains, and diamond gates with, appropriate gate signals from digital counters these drawings can be transformed (i.e., translated, rotated, magnified). Resistive summing networks and compensated current amplifiers provide the translation, while an ultralinear voltage amplifier achieves the magnification.nThis ultralinear voltage amplifier consists essentially of two two-stage amplifiers feeding a constant-current pre-output stage with negative feedback applied to the first stages.nThermal and nonthermal parameter variations are compensated for by a linearization of the used portions of the power dissipation and V versus i curves, the constant-current output stage, and circuit compensating transistor pairs.nThis topology produces an amplifier with a gain constant within 0.33 per cent, a 20 volt output range, a drift and offset voltage of less than 9 mv, and a frequency response of d-c to 1 mc with a square wave input. It can supply 10 ma at all voltage levels with an error of less than l6 mv. Component replacement is possible with no loss of accuracy.
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