These radio signals were used to determine the total electron content between the satellite and selected ground-receiving stations. The battery-powered transmitter provided internal package temperature for about 16 days and sent tracking signals for 20 days. The solar-cell-powered transmitter operated for more than six years. Signals gradually weakened and were last received at the Minitrack station in Quito, Ecuador, in May 1964. Since then the spacecraft has been tracked optically from Earth, via telescope.
These radio sign,als were used to determine the total electron content between the satellite and selected ground-receiving stations. The battery-powered transmitter provided internal package temperature for about 16 days and sent tracking signals for 20 days. The solar-cell-powered transmitter operated for more than six years. Signals gradually weakened and were last received at the Minitrack station in Quito, Ecuador, in May 1964. Since then the spacecraft has been tracked optically from Earth via telescope.