In
1965, NASA started
construction of their tracking station at Devils Ashpit. This was to provide
tracking and communications for the Gemini, Apollo, and Skylab projects. Cable
and Wireless undertook to supply them with the necessary communications.Left: ASC-1N Just before it was dismantled.
A tender was put out to Marconi Communications to design and manufacture a Satellite Earth Station. This would be the company's first Earth Station and only the fifth built worldwide.
Construction was to on Donkey Plain, the reason for this being that it was well screened from the other island installations.
The Antenna was 42ft in diameter on a tripod style mount, it was of a Non-standard design and size by Intelsat Specifications.
The station originally provided communications for NASA and DECCO in the form of Voice and Telemetry Data.
Construction was completed in 1966 with testing commencing on 10th November of that year, when the antenna locked on to an Intelsat II F1 Satellite (the signal coming from Andover E/S in the USA).
The station went to traffic on 8th April 1967 (coinciding with the operational start of NASA's Devils Ashpit site when it was connected through to Goddard Space Flight Center (via Intelsat II F3).
During the 1970's operations on ASC-1N were transferred to another Earth Station, Etam (USA).
It was also upgraded to handle 56kbit data circuits for NASA.
Up to and including 1980 all the International Telegraph and Telephone that was available on the Island were carried via the SAT-1 cable to London and Cape Town This comprised of just 2 voice circuits with 1 Telex and Telegraph Circuit.
Right: ASC-1N being dismantled and scrapped
In 1985 with the construction of a new station ASC-1N was getting old and so it was decided it should be closed down.
Some Technical Details
The Apollo equipment comprised of a ground station on the Island.
(Scroll down to picture at bottom of page)
It was built to be used for communications in connection with the moon shot project.
The fully steerable aerial carries the r.f. equipment on its backing structure and was gantry mounted.
The power supplies and servo racks were in containers at the base of the gantry.
The control console, back-up racks and receiver racks were housed in the adjacent building.
The aerial was a general purpose one capable of tracking satellites in random orbits.
Pointing was effected by 2 thyristor controlled motors, driving through a differential and gearbox, on each axis.
The whole system was servo controlled by error signals derived from the satellite beacon signal by the aerial conical scan, to give auto-follow.
Six channels were provided, 4 communications, 1 beacon signal (tracking) and 1 engineers order wire (E.O.W.).
The transmitting system was duplicated in a MAIN/STANDBY function with automatic change over in the event of failures..
