Thursday 13 December 2018

RELAY 1: THE 1ST REPEATER COMMUNICATIONS SATELLITE

Relay 1
Today, The Grandma has received the visit of Joseph de Ca'th Lon. She's still under the eternal effects of the flu and Joseph has wanted to spend the afternoon with his friend talking about one of his great passions, the astronomy. Joseph and The Grandma have been talking about Relay 1, the first repeater communications sattelite orbitted by the NASA on a day like today in 1962.

Before talking about Relay 1, The Grandma has studied a new lesson of her
Elementary Language Practice manual (Grammar 41).

More information: Might, May, Could, Can, Must I & II

The Relay program consisted of Relay 1 and Relay 2, two early American satellites in elliptical Low Earth orbit. Both were primarily experimental communications satellites funded by NASA and developed by RCA. As of December 2, 2016, both satellites were still in orbit. Relay 1 provided the first American television transmissions across the Pacific Ocean.

Relay 1 was launched atop a Delta B rocket on December 13, 1962 from LC-17A at Cape Canaveral Air Force Station. Its payload included radiation experiments designed to map the Earth's radiation belts. Apogee was 7500 km; perigee 1300. The spin-stabilized satellite had an initial spin rate of 167.3 rpm and an initial spin axis orientation with a declination of -68.3 deg and a right ascension of -56 deg.

More information: NASA

Its orbital period was 185.09 minutes. Shortly after launch, two basic problems evolved. One was the satellite's response to spurious commands, and the other was the leakage of a high-power regulator.

This leakage caused the first two weeks of satellite operation to be useless. After this period, satellite operation returned to normal. 

Project Relay
The satellite carried one transmitter for tracking and one for telemetry. The telemetry system was PCM at 1152 bit/s. Each 128 words per telemetry frame, of one s duration, used 113 words for the particle experiment.

The leakage problem caused the spacecraft to revert to a low voltage state early in 1965. Sporadic transmission occurred until February 10, 1965, after which no usable scientific data was obtained.

Relay 1 was the first satellite to broadcast television from the United States to Japan. The first broadcast during orbit 2677 was to be a prerecorded address from the president of the United States to the Japanese people, but was instead the announcement of the John F. Kennedy assassination.

On orbit 2678, this satellite carried a broadcast titled Record, Life of the Late John F. Kennedy, the first television program broadcast simultaneously in the U.S. and Japan. In later orbits, NBC transmitted coverage of the funeral procession from the White House to the cathedral. In the three days following the Kennedy assassination, Relay 1 handled a total of 11 spot broadcasts; eight to Europe and three to Japan. All the useful passes of the satellite were made available to permit immediate coverage of the tragic events.

More information: NASA

In August 1964, this satellite was used as the United States-Europe link for the broadcast of the 1964 Summer Olympics from Tokyo, after the signal was relayed to the United States via Syncom 3. This marked the first time that two satellites were used in tandem for a television broadcast.

Relay 2 was launched atop a Delta B rocket on January 21, 1964 from LC-17B at Cape Canaveral Air Force Station. Apogee 7600 km; perigee 1870 km. It was physically similar to Relay 1. Design changes in this satellite improved its performance so response to spurious commands was essentially eliminated.

One of the two onboard transponders operated normally until November 20, 1966. From that time until its failure on January 20, 1967, it required a longer time than normal to come on. The other transponder continued to operate until June 9, 1967, when it too failed to operate normally.

More information: NASA


What we do at NASA is inspiring. It's reaching, it's visionary,
and it inspires people on Earth to try hard things.

John M. Grunsfeld

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