| 摘要 |
PURPOSE:To easily detect a glazing at recording by executing the recording of a pilot signal to a PCM area with one recording reproducing system at recording mode, reproducing the recorded pilot signal with the other recording reproducing system and judging the head glazing from the reproducing signal level. CONSTITUTION:Pilot signals f1-f4 are outputted in order from a local signal generator 6 with synchronizing to a pulse (a) generated by heads 1 and 2, added to an image signal and added to recording reproducing amplifiers 3 and 4. The amplifier 3 records the pilot signal f1 from the head 1 to an image area in a period F1 which the pulse (a) is 'H', the head 2 records the pilot signal f1 to a PCM area, and in the next period F2, the head 2 records the signal f2 to the image area. Then, since a leaking component is reproduced from the adjoining signal f1, only the signal f1 is taken out by a LPF 9, mixed with the signal f2 of the local signal generator 6, and executes an envelop detection. A detection signal is compared with a reference value by a comparator 51, and when a detection signal level is higher than the reference value intermittently, a glazing signal is generated. |
