A device for translating chart recorder information into digital form
F. I. Woodward · Journal of Physics E Scientific Instruments · 1977
A low-cost instrument for digitizing chart records is described. Recorder deflection is measured by passing a needle through the chart recorder trace to make contact with one of an array of conductors. The position of the contact along the array is determined by electronic scanning and is presented on a visible display. The Y digitizer has a maximum sensitivity of 0.5% of the full-scale movement. Digitizing in the time direction is determined photoelectrically by counting the number of sprocket holes on one side of the chart. The maximum sensitivity is determined by the sprocket hole spacing.