 A 60 milliwatt transmitter fed a dipole antenna consisting of two fiberglass slot antennas in the body of the satellite operating on 108.03 MHz, and four flexible whips forming a turnstile antenna were fed by a 10 milliwatt transmitter operating on 108.00 MHz.Because of the limited space available and the requirements for low weight, the payload instrumentation was designed and built with simplicity and high reliability in mind, using germanium and silicon transistors in its electronics.A total of 29 transistors were used in Explorer 1, plus additional ones in the Army's micrometeorite amplifier.