The growth of rocketry and space technology during the course of the past few decades has given mankind a new and powerful medium for global communication in the form of satellites, which can relay messages to and from the earth, with the help of the built-in receivers and transmitters. These satellites keep revolving round the earth once in 24 hours at a height of about 36000 kms over the equator, in step with the earth's rate of rotation on its axis. They thus appear, relatively, to be stationary from any point on the earth. One such satellite can cover nearly a third of the globe, while three of them suitably distributed can cover the entire globe. Unlike conventional high frequency radio communication which works point to point, satellites link all stations in their area of coverage. This is possible on account of the wide-band capability of satellite radio relay systems. Satellites permit voice, telegraphs radio-photo and data to be relayed with ease between stations in their area of coverage. They are also the only existing means of live transoceanic television.
Satellite communications has verily opened up a new era of international cooperation which commenced with the setting up of Intelsat, the International Satellite Consortium, in 1964. This Consortium today has 77 member nations. India's participation in this international venture dates back to February, 1965 when its representative signed the agreements of the International Consortium. While the launching of the satellite and associated tracking and telemetering will be the responsibility of the Intelsat, each member country will be required to establish its earth station to work to the satellite. Accordingly a plan for the establishment of an Indian earth station and associated switching complex was drawn up as a part of the IVth Five Year Plan of Govt. of India for Oversease Communications Service, to provide the public with up-to-date facilities for international telecommunications, including international TV relay. The earth station is located at Arvi about 80 kms north of Poona on the route to Nasik. The main feature of the earth station is its large 29.6 meter diameter antenna.
The Indian Posts and Telegraphs department brought out a postage stamp to commemorate the first anniversary of the earth station Arvi, which was being dedicated to the nation by the President of India who also released the commemorative stamp. The stamp depicts the "Globe Satellite" and the location of the earth station. This station is being named the Vikram Earth Station in memory of the late Dr. Vikram Sarabhai who was primarily responsible for the execution of this sophisticated project by Indian Engineers. The First Day Cover bears a picture of the antenna at the earth station at Arvi. The stamp is depicts "Global Satellite", the course of "Intesat III" in circular lines and 'Arvi Earth Station.'
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