Abstract: A method of preparing an alignment disc pak in which first and second signals of different frequencies f1 and f2 are recorded in eccentric bands at a selected track on the disc such that the playback signal will consist of three components having frequencies f1, f2 and (f1-f2). One frame of the playback signal is first displayed with one beam of a multibeam oscilloscope on the display surface thereof such that the (f1-f2) signal component appears as a "cat's eye" pattern. The delay time base time marker is then employed to measure the time base of one of the cat's time marker is further employed to produce first and second narrow timing bands on either side of the intermediate crossover of the cat's eye pattern by erasing the recorded signals on the disc only in those radial sectors of the disc corresponding in position to two positons of the time marker on the scope as defined by the formula (Gc - Sp/2 .+-. 0.2.