The generation of a 361 MHz signal from a crystal oscillator was necessary for the first local oscillator injection for the Viking 1975 Orbiter Relay Radio Receiver. Alternative methods of generation of this 361 MHz signal include three active (transistor) doublers in cascade. However, this method normally requires higher current drain and, since it employs more components, particularly active components, is often not too reliable. Therefore, a step recovery diode, driven by a 45 MHz amplifier, was used for the X8 frequency multiplication. NASA Tech Brief. 8.5" x 11"