The resistance of the potentiometers should be a linear taper. Based on the design of the integrating analog-to-digital converter used, the maximum resistance should be no more than 528K (470K +/- 10 percent is suggested) for either the X or Y pots. This is based on a charge capacitor of 0.047uf, +/- 10 percent, and a maximum time of 16.6 milliseconds for charge to full value, ie. one video frame time. All potentiometers exhibit a certain amount of "jitter". For acceptable results on a wide base of configurations, several input readings will need to be averaged. Figure 8-6: Potentiometer Charging Circuit
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