The spacecraft body was roughly a box, approximately 3.2 × 3.3 × 2.1 m (10.5 x 10.8 x 6.9 ft) in size. The box mounted the 1.65 m (5.4 ft) dish antenna and the GPHS-RTG radioisotope thermoelectric generator (RTG) power source. The box was divided into noisy and quiet sections. The noisy section abutted the RTG; the quiet section housed the instrument electronics. Particularly "loud" components, such as the preamps for the radio dipole, were mounted outside the structure entirely, and the box acted as a Faraday cage.