| Magnetic tape|
| Analog signal|
| Magnetic recording head|Picocassette Wikipedia
Picocassette is an audio storage medium introduced by Dictaphone in collaboration with JVC in 1985. It is approximately half the size of the previous Microcassette, and was intended for highly portable dictation devices. With a tape speed of 9 millimeters per second, each cassette could hold up to 60 minutes of dictation, 30 mins per side. The signal-to-noise ratio was 35 dB. The widest dimension of the picocassette was near 4.2 cm.