| 摘要 |
Stationary record with sound grooves on a sheet of plastic material, has a generally V-shaped locating means formed on one surface of the sheet of material and is accessible to a registration pin from the same side. The V-shaped locating means comprise a recess lying in a plane generally parallel to the plane of the sheet of material. The V-shaped locating means further comprises ribs extending above the sound grooves carried by the sheet of material being located on the same surface as the V-shaped locating means. The sound grooves are arranged in a generally spiral pattern, the pattern of the sound grooves having proximate their center a point which lies in close proximity to the apex of the V-shaped locating means. |
