Signal editing system for high frequency signal magnetic recording and reproducing apparatus

Claim 2

A signal editing system for recording a second signal on a moving magnetic storage medium having a first signal already recorded thereon, said medium being in an information recorder containing an erasing head located at a first position for erasing information recorded on the storage medium and a recording head located at a second position for recording information on the storage medium, said second position being downstream in the movement of said medium from said first position, said first and second signals being frequency-modulated signals in which a carrier wave is frequency-modulated with first and second wide band signals respectively, the editing system comprising means for controlling the energization of the erasing head to erase the first signal, means for energizing the recording head for applying said second signal to the recording head, means for amplifying the carrier wave components and the upper side band components of the second signal to have a predetermined higher than normal signal level, means for amplifying the lower side band components of the second signal at a level which is decreasingly lower than said predetermined level, means for operating said amplifier for lowering said lower side band components during a period commencing at approximately the time when the erasing head is energized, said period lasting for a time interval corresponding to the interval required for a point on the storage medium to move from said first position to said second position, and means for applying the second signal to the recording head at a normal signal level after said interval.

Claim 3

The editing system as claimed in claim 1 for a helical scan, magnetic tape recorder having a guide drum containing at least one of said recording heads and a tape guideway helically surrounding said drum wherein said period commences approximately at the time when the erasing head is energized and lasts for approximately the time interval required for a point on the storage medium to move from the proximity of the first position to the proximity of the guideway into the vicinity of the guide drum.

Claim 4

a monostable multivibrator circuit containing means for switching the multivibrator from a resting state to another state upon receipt of the start signal and means for returning the multivibrator to its resting state at the end of the interval during which a portion of the second signal segment is being recorded over a portion of a first signal segment already appearing on the tape;

Claim 5

a monostable multivibrator circuit containing means for switching the multivibrator from a resting state to another state upon receipt of the start signal and means for returning the multivibrator to its resting state at the end of the interval during which a portion of the second signal segment is being recorded over a portion of a first signal segment already appearing on the tape;

Claim 6

The editing system as claimed in claim 2 wherein the period commences at the same time that the erasing head is energized.

Claim 7

a gated circuit containing means for amplifying the second signal to be recorded to a normal recording level when the multivibrator circuit is in its resting state and for amplifying the carrier wave components and the upper side band components of the second signal at a predetermined higher than normal recording level, the lower side band components of said second signal at a level which is decreasingly lowered from said predetermined level with lowering of frequencies when the multivibrator circuit is in another state;

Claim 8

a gated circuit containing means for amplifying the second signal to be recorded to a normal recording level when the multivibrator circuit is in its resting state and for amplifying the carrier wave components and the upper side band components of the second signal at a predetermined higher than normal recording level, the lower side band components of said second signal at a level which is decreasingly lowered from said predetermined level with lowering of frequencies when the multivibrator circuit is in another state;

Claim 9

The editing system as claimed in claim 2 comprising in addition: means for deenergizing the recording head, means for measuring another interval commencing when the erasing head is deenergized and ending after a period which equals the time required for a point on the magnetic medium to move from the proximity of the first position to the proximity of the guideway out of the guide drum.

Claim 10

a gate circuit containing means for transmitting a signal to be recorded to the gated circuit when the flip-flop is in the first output state and for preventing the transmission of the signal to the gated circuit when the flip-flop is in the second state; and in which said gated circuit comprises a first transistor including a base adapted to receive a signal to be recorded, a collector connected to one end of a plurality of load resistances connected in series, and an emitter connected to one end of a plurality of resistors connected in series; a second transistor including a collector connected through a first capacitor to an intermediate connecting point of said plurality of load resistances, and an emitter connected to the other end of said plurality of resistors; a third transistor including a collector connected through a second capacitor to an intermediate connecting point of said plurality of resistors, and an emitter connected to the other end of said plurality of resistors; and means for biasing in a reverse direction the voltage across the base and emitter of said second and third transistors when said monostable multivibrator is in the resting state and biasing in a normal direction the voltage across the base and emitter of said second and third transistors; the value of the electrostatic capacity of said first capacitor being selected such that it provides a sufficiently low impedance in the frequency range of the lower side band of said second signal, the value of the electrostatic capacity of said second capacitor being selected such that it provides a sufficiently lower impedance than the value of resistance between said other end of said plurality of resistors and said intermediate connecting point to which said second capacitor is connected with respect to the frequency range of the carrier wave and the upper side band of said second signal and provides a sufficiently higher impedance than said value of resistance with respect to the lower frequencies of the lower side band of the said second signal.

Claim 11

a gate circuit containing means for transmitting a signal to be recorded to the gated circuit when the flip-flop is in the first output state and for preventing the transmission of the signal to the gated circuit when the flip-flop is in the second state; and in which said gated circuit comprises a first transistor including a base adapted to receive a signal to be recorded, a collector connected to one end of a plurality of load resistances connected in series, and an emitter connected to one end of a plurality of resistors connected in series; a second transistor including a collector connected through a first capacitor to an intermediate connecting point of said plurality of load resistances, and an emitter connected to the other end of said plurality of resistors; a third transistor including a collector connected through a second capacitor to an intermediate connecting point of said plurality of resistors, and an emitter connected to the other end of said plurality of resistors; and means for biasing in a reverse direction the voltage across the base and emitter of said second and third transistors when said monostable multivibrator is in the resting state and biasing in a normal direction the voltage across the base and emitter of said second and third transistors; the value of the electrostatic capacity of said first capacitor being selected such that it provides a sufficiently low impedance in the frequency range of the lower side band of said second signal, the value of the electrostatic capacity of said second capacitor being selected such that it provides a sufficiently lower impedance than the value of resistance between said other end of said plurality of resistors and said intermediate connecting point to which said second capacitor is connected with respect to the frequency range of the carrier wave and the upper side band of said second signal and provides a sufficiently higher impedance than said value of resistance with respect to the lower frequencies of the lower side band of the said second signal.

Claim 12

The editing system as claimed in claim 2 wherein the means for energizing the recording head comprise first control means comprising a flip-flop circuit, means associated with said control means for switching flip-flop into a first output state responsive to the receipt of a start signal indicating the beginning of a second signal segment to be recorded, means for thereafter switching the flip-flop into a second output state responsive to the receipt of a reset signal indicating the end of the second signal segment which has been recorded, second control means comprising a monostable multivibrator circuit, means for switching the multivibrator from a resting state to another state responsive to the receipt of the sTart signal, means responsive to the monostable characteristics of said multivibrator for returning the multivibrator to its resting state at the end of an automatically occurring interval, means effective during the interval while said multivibrator is in said other state for recording at least a portion of the second signal over a portion of the first signal previously recorded on the tape, means comprising a gated circuit containing means responsive to the multivibrator circuit when it is in its resting state for amplifying at a normal recording level the second signal to be recorded, means responsive to said multivibrator in said other state for amplifying the carrier wave components and the upper side band components of the second signal at a predetermined higher than normal recording level, means also responsive to said multivibrator in said other state for amplifying the lower side band components of said second signal at a level which is decreasingly lowered as a function of the lowering of frequencies in said lower side band, and means comprising a gate circuit containing means for transmitting a signal to be recorded to the gated circuit means when the flip-flop is in the first output state and for preventing the transmission of the signal to the gated circuit when the flip-flop is in the second state.

Claim 13

The editing system as defined in claim 5 wherein the means comprising the flip-flop circuit comprises in addition: means for delaying the switching of the flip-flop into the second state for an interval commencing with the receipt of said reset pulse and lasting for a period which is equal to the time which is required for a point on the magnetic tape to travel from the erasing head to the last point at which the recording head can record a signal on the tape.

Claim 14

A signal editing system for recording a second signal on a moving magnetic storage medium whereon a first signal is already recorded in an information recorder containing an erasing head located at a first position for erasing information recorded on the storage medium and a recording head located at a second position for recording information on the storage medium, said first and second signals being frequency-modulated signals in which a carrier wave is frequency-modulated with first and second wide band signals respectively, the editing system comprising: a. means for controlling the energization of the erasing head to erase the first signal; b. means for energizing the recording head including means for applying to the recording head the carrier wave components and the upper side band components of the second signal at a predetermined higher than normal signal level and the lower side band components of the second signal at a level which is decreasingly lowered from said predetermined level with lowering of frequencies during a period commencing approximately at the same time as the time at which the erasing head is energized and lasting for a time interval required for a point on the storage medium to move from said first position to said second position, and means for applying the second signal to the recording head at a normal signal level after said period; c. said information recorded further comprising a guide drum and a guideway for directing magnetic tape in a helical path around said drum, said guide drum containing recording heads wherein said period commences approximately at the same time as the time at which the erasing head is energized and lasts for approximately the same time interval as that required for a point on the storage medium to move from the proximity of the first position to the proximity of the way-in of the guide drum; d. said means for energizing the recording head further comprising:

Claim 15

A signal editing system for recording a second signal on a moving magnetic storage medium whereon a first signal is already recorded in an information recorder containing an erasing head located at a first position for erasing information recorded on the storage medium and a recording head located at a second position for recording information on the storage medium, said first and second signals being frequency-modulated signals in which a carrier wave is frequency-modulated with first and second wide band signals respectively, the editing system comprising: a. means for controlling the energization of the erasing head to erase the first signal; b. means for energizing the recording head including means for applying to the recording head the carrier wave components and the upper side band components of the second signal at a predetermined higher than normal signal level and the lower side band components of the second signal at a level which is decreasingly lowered from said predetermined level with lowering of frequencies during a period commencing approximately at the same time as the time at which the erasing head is energized and lasting for a time interval required for a point on the storage medium to move from said first position to said second position, and means for applying the second signal to the recording head at a normal signal level after said period; c. said information recorded further comprising a guide drum and a guideway for directing magnetic tape in a helical path around said drum, said guide drum containing recording heads wherein said period commences approximately at the same time as the time at which the erasing head is energized and lasts for approximately the same time interval as that required for a point on the storage medium to move from the proximity of the first position to the proximity of the way-in of the guide drum; d. said means for energizing the recording head further comprising: