PURPOSE: To enable attainment of operability being equivalent to the one of a CRT display device even by a device using a recorder, by computing a scale division width and a frequency corresponding to a band and width of analysis of the frequency from frequency analysis parameters and by displaying a frequency scale thus obtained.

CONSTITUTION: A central frequency f0 and a frequency (w) to be analyzed are inputted as frequency analysis parameters FAP to an arithmetic device 1. When the recording center is fixed on a recording surface of a recorder, on the occasion, a position x0 indicating a scale division and a numeric value thereof can be determined, and a position ±xn (n = 1, 2, 3...) of indication of a minimum scale division can be determined by x0 ±n × (w), while a position x5n of a scale division of a marking-off place such as 5 or 10 can be determined by x0 ±5 × (n) × (w). The arithmetic device 1 outputs the results of these computations to a display device 2 and they are displayed therein. Thereby an operator can conduct an operation easily by using a displayed corresponding scale, without changing a frequency scale, even when a band and a width of analysis of the frequency are varied.