A four-head type magnetic recording and/or reproducing apparatus having two mutually orthogonal pairs of video heads for recording and/or reproducing video signals on videotape, each of said pairs of video heads having a first video head and a second video head opposite to said first video head, said apparatus having a function of electronically splicing a record of video signals to another record of video signals previously recorded on videotape, said four-head type magnetic recording and/or reproducing apparatus comprising:
- a control head for recording and/or reproducing control signals on the videotape;
- control signal reproducing means connected to said control head for reproducing recorded control signals from the videotape;
- control signal detecting means, connected to receive a control signal reproduced by said control signal reproducing means, for comparing the duty factor of the reproduced control signal with predetermined first to fourth reference values to detect whether the received control signal is a normal code signal having a duty factor the value of which is one of first and second values or is an indication signal corresponding to an electronic splicing operation and having a duty factor the value of which is one of third and fourth values, and for outputting a signal representing information on the results of the detection, the first value being predetermined to be less than the second value, the third value being predetermined to be less than the fourth value and to be nearly equal to the second value, the first reference value being predetermined to be less than the first value, the second reference value being predetermined to be less than the first value and greater than the first reference value, the third reference value being predetermined to normally be greater than each of the first value and the second reference value and less than the second value, said control signal detecting means changing the third reference value to a fifth reference value less than the fourth value and greater than each of the second and third values when said signal detecting means receives a reproduced control signal having a duty factor greater than each of the second and third values, the fourth reference value being predetermined to normally be greater than the third value, said control signal detecting means changing the fourth reference value to a sixth reference value less than each of the second and third values and greater than the first value when said signal detecting means receives a reproduced control signal having a duty factor greater than each of the second and third values;
- control means, connected to receive the signal outputted by said control signal detecting means, for controlling operations of normal recording of video signals and control signals on the videotape and reproducing recorded video signals and control signals from the videotape and for controlling an electronic splicing operation in such a manner as to prevent one of said first and second video heads from reproducing video signals recorded by the other of said first and second video heads according to the signal received from said control signal. detecting means and for outputting a signal representing an instruction that a normal code signal or an indication signal should be recorded on the videotape;
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- control signal recording means connected to both of said control means and said control head for receiving the signal outputted by said control means, and for generating normal code signals and indication signals in response to the signal received from said control means, for alternately outputting the generated normal code signal having a duty factor of the first value and the generated normal code signal having a duty factor of the second value to said control head, to prevent one of said first and second video heads from reproducing video signals recorded by the other of said first and second video heads so as to perform the recording and reproducing of the video signals by an identical video head, or for alternately outputting the generated indication signal having a duty factor of the fourth value and the generated normal code signal having a duty factor of the third value to said control head.