Abstract: An apparatus for modifying a video signal to protect the unauthorized recording and reproduction thereof is disclosed. In accordance with the invention, the video signal is modified in such a manner that insufficient vertical synchronization information is contained in some, but not all, of the vertical blanking intervals. Particularly, insufficient vertical synchronization information is contained in a sequence of vertical blanking intervals which will cause the rotational velocity of the tape head of the VTR to constantly vary.

Abstract: A foot exercising device is disclosed. The foot exercising device includes a pair of foot pedals and a motor for reciprocating the foot pedals. A slip clutch is connected between the foot pedals and the motor to enable the foot pedals to be reciprocated independently of the motor. In the preferred embodiment, a control circuit controls the operation of the motor as a function of the number of reciprocations of the foot pedals and/or as a function of the blood flow through the patient using the foot exercising device.

Abstract: A foot exercising device is disclosed. The foot exercising device includes a pair of foot pedals and a motor for reciprocating the foot pedals. A slip clutch is connected between the foot pedals and the motor to enable the foot pedals to be reciprocated independently of the motor. In the preferred embodiment, a control circuit controls the operation of the motor as a function of the number of reciprocations of the foot pedals and/or as a function of the blood flow through the patient using the foot exercising device.

Abstract: A foot exercising device is disclosed. The foot exercising device includes a pair of foot pedals and a motor for reciprocating the foot pedals. A slip clutch is connected between the foot pedals and the motor to enable the foot pedals to be reciprocated independently of the motor. In the preferred embodiment, a control circuit controls the operation of the motor as a function of the number of reciprocations of the foot pedals and/or as a function of the blood flow through the patient using the foot exercising device.

Abstract: A foot exercising device is disclosed. The foot exercising device includes a pair of foot pedals and a motor for reciprocating the foot pedals. A slip clutch is connected between the foot pedals and the motor to enable the foot pedals to be reciprocated independently of the motor. In the preferred embodiment, a control circuit controls the operation of the motor as a function of the number of reciprocations of the foot pedals and/or as a function of the blood flow through the patient using the foot exercising device.

Abstract: A foot exercising device is disclosed. The foot exercising device includes a pair of foot pedals and a motor for reciprocating the foot pedals. A slip clutch is connected between the foot pedals and the motor to enable the foot pedals to be reciprocated independently of the motor. In the preferred embodiment, a control circuit controls the operation of the motor as a function of the number of reciprocations of the foot pedals and/or as a function of the blood flow through the patient using the foot exercising device.

Abstract: An ultrasonic display apparatus which utilizes novel electrical and optical means to produce an image which is spatially superimposed within the exact area of the patient's body being scanned is disclosed. The ultrasonic display apparatus includes a cathode ray tube, a planar mirror and a transducer which are mounted within a housing having a viewing window formed therein. The cathode ray tube includes a generally planar viewing face which lies in a first plane. The planar mirror lies in a second plane. One of the mirror and cathode ray tube is pivotally mounted within the housing such that the angle between the first and second planes is adjustable. The transducer is pivotally mounted in the housing and is connected to electric circuit means which cause the transducer to generate a succession of ultrasonic beams which propagate along a third plane. Angle adjustment means are provided for adjusting the angle of the third plane with respect to the housing.

Abstract: A method and system of electronic image storage and display wherein the display is viewed on a raster scan TV display and the incoming signal comprises a sequence of scan lines whose line rate is lower than that of the horizontal TV line rate and is an integer submultiple, preferably even, thereof. The incoming signal is stored in the memory of a scan converter and the stored image is scanned and displayed on a conventional television raster scan display.The scan converter mode is alternated between read and write such that the writing is carried out during the time required to scan one horizontal TV line in the field and the reading is carried out during the time required to scan the next horizontal TV line in the field to thereby write and read during alternate horizontal TV lines.To produce a spatially uniform raster, the horizontal TV lines of succeeding TV fields are offset by one line from the horizontal TV lines of the preceding field.

Abstract: A method and system of electronic image storage and display wherein the display is viewed on a raster scan TV display and the incoming signal comprises a sequence of scan lines whose line rate is lower than that of the horizontal TV line rate within a field of the TV display and is an odd integer submultiple thereof. The incoming signal is stored in the memory of a scan converter and the stored image is scanned and displayed on a conventional television raster scan display.The scan converter mode is alternated between read and write such that the writing is carried out during the time required to scan one horizontal TV line in the field and the reading is carried out during the time required to scan the next horizontal TV line in the field to thereby write and read on alternate horizontal lines of the same field.To produce a spatially uniform raster, the horizontal TV lines of alternate TV fields are offset by one line from the horizontal TV lines of the preceding field.

Abstract: An electronic storage tube of the electron beam modulated type employing a target structure of the "coplanar grid" type in which the coplanar grid is a multilayered structure having at least one layer thereof which is more immune to ionizing radiation, such as X-rays, than at least one of the remaining layers, to yield a target structure in which erasure time and retention time are both significantly improved even though the stored pattern is repetitively read out.A method is also described herein for operating target structures of the type described hereinabove to take advantage of the above mentioned advantageous characteristics and thereby yield an electronic storage tube having operating characteristics not heretofore capable of being provided in conventional structures.

Abstract: A target structure for electronic storage tubes which is of the "coplanar grid" type. The target comprises a conducting layer which in a preferred configuration has slender elongated pedestals supporting elongated spaced parallel insulating strips which serve as the coplanar grid. The spaces between adjacent edges of insulating strips expose regions of the conducting layer to enable an electron beam to contact the exposed regions of the conducting layer. The pedestals support the insulating strips a spaced distance above the exposed regions of the conducting layer to form "vacuum gaps" which serve to inhibit electrical charge on the surfaces of the insulating strips from transferring to the interface between each strip and the vacuum gap. The pedestals may be an integral part of the conducting layer or may be formed from an insulating material. Methods for producing the novel target are described.