DIGITAL FREQUENCY MODULATION CONVERTER

• Main Authors: KOJIMA MASANORI, MITOMI YASUSHI
• Format: Patent
• Language: English
• Published: 18.08.1987
• Subjects: BASIC ELECTRONIC CIRCUITRY; ELECTRICITY; INFORMATION STORAGE; INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORDCARRIER AND TRANSDUCER; PHYSICS; PULSE TECHNIQUE

PURPOSE:To decrease noise, distortion and the deterioration in performance in the transient characteristic in the stage of signal processing by converting a digital signal into an analog signal to change directly the oscillating frequency of an astable multivibrator. CONSTITUTION:A current between the collector and emitter of both transistors (TRs) TR5, TR6 is changed when an impedance between the emitters and ground of the TRs TR5, TR6 is fluctuated in the astable multivibrator 20, then a charge/ discharge time of a capacitor C has a change, the oscillation frequency of the astable multivibrator 20 is fluctuated accordingly and an FM signal is obtained from an FM signal output terminal 11. A digital signal from a digital signal generating section 2 is inputted to an FM converter 10 to obtain an FM output signal, which is recorded in a recording section 8. Thus, the generation of noise, distortion and deterioration in the transient characteristic in the process of digital/analog conversion is reduced more than a conventional converter.