PROCEDIMIENTO PARA LA OBTENCION DE UNA MATRIZ DE METAL PROVISTA DE UNA MODULACION DE SURCO

摘要

A groove modulation is cut into a signal recording medium by means of a cutting stylus (1) which cuts into the groove at an angle of attack between 10 deg. and 20 deg. The copper layer composing the surface of the recording medium has a Vickers hardness between 110 and 300, preferably between 120 and 220. - The groove modulation may be cut into a copper surface layer (3) applied galvanically to the recording medium. The groove modulation may be cut in by means of a diamond.