Location
Cocoa Beach, FL
Start Date
7-3-1966 8:00 AM
Description
The Dielectric-Tape Television Camera, including the subject logic and control system, is being developed for use in a meteorological satellite which will be placed in a polar orbit hundreds of miles above the surface of the Earth. This camera is being developed by the Astro-Electronics Division of RCA for the NASA Goddard Space Flight Center under contract NAS5 -2503.
Dielectric tape is a 35-millimeter-wide, transparent plastic material which is covered with a transparent conducting layer of evaporated gold to provide electrical contact with one side of the photoconductor. The gold is coated with a photoconductive layer which is, in turn, coated with a thin, very uniform, insulating layer of polystyrene.
The function of the camera, as depicted in Figure 1, is to provide high-quality panoramic pictures of the Earth1 s cloud cover. This is accomplished by recording the desired image on the dielectric tape in the form of a charge pattern. Later, when the satellite is over the ground station, the charge pattern is converted into an electrical signal which is transmitted to Earth where it will be permanently recorded on a graphic medium.
The camera is controlled primarily by three commands: Write (record), Read (playback), and Off. An additional eleven commands are used for peripheral and back-up operations. The commands are either transmitted from the ground station to the camera directly or they are stored in the satellite computer for a specified period of time.
The logic and control system has been designed to accept these commands and automatically direct the camera to perform the numerous functions characteristic of each mode of operation.
In the following sections, the operation of the camera is described in order to provide a general understanding of what is required of the control system. Particular emphasis is given to that part of the control system which synchronizes the retrace or "flyback" of the scanning mirror to the cycle of time code being recorded on the tape for identifying adjacent picture frames.
Logic and Control Systems for a Panoramic Television Camera
Cocoa Beach, FL
The Dielectric-Tape Television Camera, including the subject logic and control system, is being developed for use in a meteorological satellite which will be placed in a polar orbit hundreds of miles above the surface of the Earth. This camera is being developed by the Astro-Electronics Division of RCA for the NASA Goddard Space Flight Center under contract NAS5 -2503.
Dielectric tape is a 35-millimeter-wide, transparent plastic material which is covered with a transparent conducting layer of evaporated gold to provide electrical contact with one side of the photoconductor. The gold is coated with a photoconductive layer which is, in turn, coated with a thin, very uniform, insulating layer of polystyrene.
The function of the camera, as depicted in Figure 1, is to provide high-quality panoramic pictures of the Earth1 s cloud cover. This is accomplished by recording the desired image on the dielectric tape in the form of a charge pattern. Later, when the satellite is over the ground station, the charge pattern is converted into an electrical signal which is transmitted to Earth where it will be permanently recorded on a graphic medium.
The camera is controlled primarily by three commands: Write (record), Read (playback), and Off. An additional eleven commands are used for peripheral and back-up operations. The commands are either transmitted from the ground station to the camera directly or they are stored in the satellite computer for a specified period of time.
The logic and control system has been designed to accept these commands and automatically direct the camera to perform the numerous functions characteristic of each mode of operation.
In the following sections, the operation of the camera is described in order to provide a general understanding of what is required of the control system. Particular emphasis is given to that part of the control system which synchronizes the retrace or "flyback" of the scanning mirror to the cycle of time code being recorded on the tape for identifying adjacent picture frames.
