Title:
DEVICE FOR DISCRIMINATING RECORDING SYSTEM OF FREQUENCY MODULATED VIDEO SIGNAL
Document Type and Number:
Japanese Patent JPH0312863
Kind Code:
A
Abstract:
PURPOSE:To automatically discriminate the recording system of an FM modulation video signal by setting the output level of an FM demodulation circuit when a reference signal having the intermediate frequency of frequencies in specified parts of two kinds of the FM modulated video signals is given to an FM demodulation circuit as a reference level and discriminating demodulation output levels of the specified parts. CONSTITUTION:The FM demodulation circuit has the parts where an output voltage linearly changes for the frequency of an input signal and the parts are used for FM demodulation. Namely, the characteristic of the demodulation circuit 14 has linear parts and the frequency of the reference signal is the middle of the sync chip frequency of high band recording and the sync chip frequency of normal band recording. Thus, the reference level VS comes to the medium of the sync chip level VH of high band recording after demodulation and the sync chip level VN of normal band recording. Thus, the reference level VS and the sync chip level VH or VN are detected and compared. Thus, it can be discriminated whether the recording system of the RF signal is normal band recording or high band recording.
Inventors:
FUKADA JUICHI
Application Number:
JP14679589A
Publication Date:
January 21, 1991
Filing Date:
June 12, 1989
Export Citation:
Assignee:
FUJI PHOTO FILM CO LTD
International Classes:
H04N5/922; G11B20/06; H04N5/92; (IPC1-7): G11B20/06; H04N5/92
Domestic Patent References:
| JPS62291277A | 1987-12-18 | |||
| JPS61260462A | 1986-11-18 | |||
| JP63074879B |
Attorney, Agent or Firm:
Kenji Ushiku
Next Patent: VIDEO TAPE RECORDER