Like their Earth-bound counterparts in the DSN, the Voyager antennas are a Cassegrain reflector design, which uses a Frequency Selective Subreflector (FSS) at the focus of the primary reflector.

The 24-inch Boller & Chivens f/8 Cassegrain was installed in the dome of Sommers-Bausch Observatory in 1973 ... historical left-overs from the transition between the long-and-narrow refractor and its ...