The resistor plate is a circular 2-layer PCB with a stepper motor at its center, resistors around its circumference at equal angular offsets, and a copper mechanical arm assembly. The shape of the board enables the stepper motor to select different series resistor combinations. The resistors form an open circular track around the PCB and the positive input terminal is connected just before the smallest value resistor on the resistor track. The smallest and largest value resistors are not directly connected to each other, breaking the resistor track. The negative input terminal connects to GND, which is connected to the mechanical arm assembly. Therefore, the current path flows between the positive terminal, through the resistors between the positive terminal and the mechanical arm, and finally through the mechanical arm into the GND layer of the board and back into the negative terminal. The resistor plate also contains an input port for a reference voltage, a low current fuse for this reference, and a small resistor. The reference voltage, small resistor, and the portion of resistor track which are not used in generating the load, are used in implementing feedback control over the stepper motor.