Another harmonic analyzer

Modern alternating-current engineering involves the necessity of frequently analyzing curves for harmonics. All of the methods of analysis have more or less serious objections. A method based upon the averaging of ordinates selected at the proper intervals has been developed into a machine which is reasonably simple and cheap to construct and can be operated without great skill. The machine depends chiefly for its operation upon a bar containing notches at the proper intervals and each bar is suitable for curves of the same plotted wave length. It is thus limited to curves plotted with the same scale of abscissas, but different bars may be manufactured for different scales and the machine thus adopted to various types of curves. A comparison with the times required for harmonic analysis by different methods shows that it compares favorably with other devices.