Andover Earth Station

Other factors included a location in the Northeastern United States to give a short great circle path to Western Europe, it was located close enough to existing transcontinental radio relay television and telephone routes to facilitate interconnection.

In addition, the site had to be large enough to accommodate an antenna structure and control building, and if necessary, provide room for expansion.

The radio transmitter aboard Telstar was very low-powered compared to modern communication satellites, with a power of only 14 watts, and transmitted through an omnidirectional antenna, so the ground antennas that communicated with it had to be huge, with very large apertures to receive enough radio power from the satellite to be intelligible.

The Andover Earth Station was equipped with a giant horn antenna, 7 stories high and weighing 340 tons.

The engineers successfully sent a signal to Telstar, which amplified it 10 billion times and relayed it back to Andover.

The 7-story tall horn antenna within the radome at Andover Earth Station. This type of antenna is called a Hogg or horn-reflector antenna, invented by Albert Beck and Harald Friis in 1941 and further developed by D. L. Hogg at Bell Telephone Laboratories in 1961. It consists of a flaring metal horn with a metal paraboloidal reflector mounted in the mouth at a 45° angle. The advantage of this design over a parabolic dish antenna is that it has very low sidelobes ; that is, the horn shields the antenna from radiation from angles outside the main beam axis, such as ground noise.
Aerial view of Andover Earth Station
Aerial view of Andover Earth Station taken on 20 July 2022