Launch Date: 1964-07-28
On-orbit dry mass: 361.80 kg
Nominal Power Output: 200.00 W
There were two camera channels which had independent power distribution networks so that the greatest reliability and probability of obtaining highest quality video pictures would be afforded. The first channel had two full-scan cameras, one wide angle (25-degree field of view and 25-millimeter focal length) designated the A-camera and one narrow angle (8.4 degree field of view and 76-millimeter focal length) B-camera. These cameras utilized an active image area of 11 square millimeter that contained 1150 lines and was scanned in 2.5 seconds. Scan and erase cycles were designed to act alternately resulting in intervals of 5 seconds between consecutive pictures on a particular camera. The other channel had four partial-scan p-cameras, two narrow angle and two wide angle. The image area of these four cameras was 2.8 square millimeters which contained 300 lines and was scanned in 0.2 seconds. The instrument allowed for camera fields of view, ranging from 25 degrees to 2.1 degrees, to overlap and produce a 'nesting' sequence of pictures. The video transmissions were recorded on both kinoscope film recorders and magnetic tape recorders. A cathode-ray tube reconstructed the original image, which was then photographed on 35-millimeter film.
The full-scan camera system began transmitting pictures at 1308 UT on July 31, 1964, 17 minutes, 13 seconds prior to impact. The partial-scan system initiated transmission of pictures at 1312 UT, 13 minutes, 40 seconds prior to impact. The last full-scan transmission occured between 2.5 and 5 seconds before impact, while the last partial-scan picture was taken between 0.2 and 0.4 seconds before impact and achieved resolution to 0.5 meters (1.64 feet). Image motion is more severe in the last pictures. The experiment returned 4,308 photographs of excellent quality.
Space History Ranger to the Moon