A transformer has three secondaries, 1) a high voltage center tapped, 2) a 5 volt, and 3) a 6.3 volt. The tap on the h v is grounded and the ends of the winding go to the plates of a vacuum rectifier like the 5Y3 or 5U4. Each side of the filament goes to each side of the 5 volt winding. One of the filament connections goes to the positive of a cap labeled C1. This point goes to one end of a filter choke labeled L. The other end of the choke goes to the positive of C2. The negative ends of C1 and C2 are grounded. The output terminals come from the positive of C2 and ground. End verbal description.