Optimizing of balances of the second generation

At the 3rd Conference on Vacuum Microbalance Techniques in Los Angeles in 1 962, we suggested the use of the equation of motion of a balance T=J+alphak(alpha) over dot + C alpha for the calculation of the unknown torque T, an d the measurement for that purpose of the values of all the other quantitie s in this equation. The present paper discusses the consequences of two sou rces of error relevant for this method. First, the errors caused in the fir st and second derivatives of the deflection are considered, deduced from tw o or three deflection measurements separated by small time intervals. Secon dly, the consequences of the errors caused by the uncertainties in the defl ection measurements are discussed. Consideration of the two errors together leads to an optimal set of values of parameters for the balance handling.