| 摘要 |
PURPOSE:To effectively erase a recorded signal, in other words, to the same extent as a direct current erasing, and also in a short time, by constituting a circuit so that an erase carrier in which a frequency changes gradually is generated by a simplified circuit. CONSTITUTION:An erase control circuit 300 in which corresponding resistances R11-R1n connected in series respectively to n-number of transistors Q11-Q1n are connected in parallel with a control line 302, consists of a current controlled circuit to adjust a current on the control line 302 corresponding to a control signal inputted from a control circuit 12 to the base electrodes 92a-92n of the transistors. In other words, the current decided by the energizing states of those transistors Q11-Q1n is supplied to the terminal #12 of a frequency oscillator 200. The values of the resistances R11, and R2-R5 are selected so as to change the output frequency of the terminal #11 of the frequency oscillator 200 in five stages corresponding to the energizing of the transistors Q11-Q15.
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