Historical Photo of the Month – June 2010

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RF Voltage Breakdown Facility

Photograph Number 333-4315Ac

The vacuum of space can cause a short circuit in microwave components, resulting in disruption or loss of communications, or even permanent damage to the components. Radio frequency voltage breakdown caused the failure of the Ranger 6 television camera system, but was found and fixed in time for the Ranger 7 mission in July 1964. Even so, the problem required additional study in order to prepare for increasingly complex missions to the moon and planets.

In early 1964, engineer Richard Woo came to JPL with an assignment: conduct research on RF voltage breakdown, including a phenomenon called multipacting, and design and build a facility to support it. The Antenna Laboratory (Building 212) already existed, but an anechoic chamber (the room lined with microwave-absorbing foam cones) and a control room were added in 1966. The Plexiglas vacuum chamber was installed in June 1967 to complete the RF Voltage Breakdown Facility. Mechanical engineer Eugene Noller and Richard Woo can be seen at the control room window during a March 1968 antenna test.

For more information about the RF Voltage Breakdown Facility and about the history of JPL, contact the JPL Archives for assistance. [Archival and other sources: Richard Woo; Final Report on RF Voltage Breakdown in Coaxial Transmission Lines, R. Woo, October 1, 1970, TR 32-1500; Multipacting and Ionization Breakdown Studies, S.A. Brunstein and R. Woo, October 31, 1965, SPS 37-35, Vol. IV; JB and Section 333 photo albums.