 TV signal decoding apparatus using luminance and color signal selection |
| To solve the above problems, the present invention offers an EDTV signal decoding apparatus which ... |
|
| Low cost high efficiency power converter |
| A new circuit for switch mode power converters achieves high efficiency and zero voltage switching ... |
|
| Multi-channel video switch using dual-gate MOS-FETS |
| In accordance with the present invention a video switch circuit provides alternate connection of ... |
|
| Television generator for highlighting portions of an image |
| As described above, according to the prior art, hardware is increased in volume and high-speed ... |
|
| Holograms for security markings |
| According to a first aspect of this invention there is provided a hologram for security markings ... |
|
| Chrominance signal processing circuit in color television receiver |
| Briefly described, the present invention comprises a chrominance signal processing circuit in a ... |
|
| Image recording apparatus |
| I claim: 1. An image recording apparatus comprising: a raster scan display screen for displaying an ... |
|
| FM demodulator having a frequency independent delay circuit |
| An object of the present invention is to provide an FM demodulator, employing delay circuits, which ... |
|
|
Video recording and reproducing device and method including video signal record restart during rewind/playback operation after non-detection of pilot signal in video track
| Details |
Inventors: Okumura, Nobuyoshi;
Assignee: Mitsubishi Denki Kabushiki Kaisha (Tokyo, JP)
Primary Examiner: Faber; Alan
Assistant Examiner: Young; W. R.
Attorney, Agent or Firm: Staas & Halsey
A magnetic recording and reproducing device and method, the device including rotary heads, a pilot signal generating circuit for generating pilot signals different in frequency in synchronization with a change-over signal for the rotary heads. Also included are an adder for superposing the pilot signals on a video signal and applying the resultant signals to the rotary heads, a first switch for stopping the delivery of the pilot signals for a predetermined period of time in a temporary recording stop mode, and a second switch for switching the operation mode of the rotary heads from a recording mode over to a reproducing mode so that, after the first switch has stopped the delivery of the pilot signals, the delivery of signals from the adder is stopped. Further included are a pilot signal extracting circuit for extracting a reproduced pilot signal reproduced from the magnetic tape, and a magnetic tape running control circuit which, after the second switch switches the operation mode of the rotary heads, rewinds the magnetic tape by a predetermined lenght, stops the tape, and controls the running of the tape in the forward direction so that the frequency of the pilot signal from the pilot signal extracting circuit coincides with that of the pilot signal from the pilot signal generating cirucit, in a temporary recording stop removal mode. A pilot signal discriminating circuit is also included for switching the operation mode of the second switch from a reproducing mode over to a recording mode when the level of the pilot signal from the pilot signal extracting cirucit is lower than a predetermined value. |
|
DETAILED DESCRIPTION In view of the foregoing, an object of the present invention is to provide a rotary head type magnetic recording and reproducing device in which, instead of fixed heads such as audio heads, rotary heads are employed to carry out successive picture recording using pilot signals.
It is another object of the present invention to provide successive picture recording without signal overlap or signal gaps.
It is a further object of the present invention to provide a different frequency pilot signal on each track to increase the ease of detecting the pilot signal and control tracking.
The above objects of the present invention can be achieved by a magnetic recording and reproducing device and method which uses an adder for superposing a tracking pilot signal on a video signal and a rotary head for recording an output signal of the adder in video tracks on a magnetic tape and reproducing the output signal thus recorded.
In addition, switching means is included for stopping the delivery of the pilot signal and stopping the recording operation beginning with the video track next to the video track on which the pilot signal has been stopped when in a temporary recording stop mode.
A pilot signal discriminating circuit is also included for detecting the video track on which the pilot signal has been stopped, and starting a recording operation beginning with the video track next to the video track on which the pilot signal has been stopped when in a temporary recording stop removal mode.
These together with other objects and advantages which will be subsequently apparent, reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout.
|
|
TV Signal 
