Scoposcopy: Tek RM503 Lissajous Figures with Audio
RM503 displaying Lissajous aka Bowditch figures, with Audio. Two oscillators send their frequencies to loudspeakers, and to the horizontal and vertical channels of the RM503 precision low-frequency oscilloscope. The Philips counter displays the ratio of the horizontal and vertical freqencies. Note that the stable and interesting patterns are associated with pleasant, consonant sounds and small integer ratios, like 1/1, 1/2, 2/1, 3/2, 2/3, 5/3, and so on.