5000PF 1KV Moulded Paper Capacitor engineered for mid-century tube-based electronic equipment.It features an electrical capacitance rating of 0.005 microfarads (0.005 µf / 5000 pF) and is built to handle a maximum operating potential of 1000 Volts DC.The primary component construction consists of layered foil and dielectric paper encapsulated in a hard, protective molded resin shell designed to seal out humidity and environmental moisture.It serves as a critical circuit element designated as C38 or C9 within standard schematics, providing reliable audio coupling, high-voltage filtering, or RF bypassing.Industry Equivalents (Cross-References)The Sprague "Black Beauty" 160P series is a prominent mid-century alternative that matches the molded resin configuration, 0.005 µf capacitance value, and 1000V dielectric voltage rating.The Cornell Dubilier "Tiger Cub" series serves as a direct axial-lead alternative, providing matching insulation resistances and physical sizing for vintage point-to-point chassis paths.The Mallory PVC1055 functions as a highly reliable film-based replacement variant, offering upgraded polyester dielectric properties while dropping into the exact same circuit location.The Vishay Roederstein MKT1813 serves as a modern, high-precision metalized polyester film equivalent, updating the structural safety margins while maintaining the original circuit timing profile.History of the ComponentThe lineage of this component belongs to the Radio Corporation of America (RCA), the foundational titan of early American broadcasting, television engineering, and vacuum tube circuit design. The 72220 capacitor was introduced during the post-WWII manufacturing boom of the late 1940s to support the extreme voltage demands of home radio receivers, early television sets, and test instruments.During this historical era, standard wax-dipped paper capacitors frequently degraded due to internal moisture absorption, causing electrical leakage that could destroy expensive audio transformers or vacuum tubes. RCA introduced these hard, molded-case paper variants under their official service data registry to maximize field reliability and standardize internal factory assemblies.As the electronics sector fully migrated toward modern, non-inductive polyester and polypropylene film capacitors in the 1960s and 1970s, molded paper units were completely phased out. Today, original new-old-stock (NOS) components are tracked by vintage electronic conservators to preserve the authentic physical layouts of historic tube gear.Actual Product Applications (Makes and Models)The RCA Victor Model 612V3 Console Radio-Phonograph (1947) integrated the 72220 capacitor directly into its primary vacuum tube power supply filter assembly to smooth out residual AC line ripple.The RCA Victor Model 8-X-541 AM Tabletop Radio utilized this 1000-volt component across its audio output stage to bypass high-frequency harmonic distortion before it reached the loudspeaker transformer.The RCA WV-77E VoltOhmyst Vacuum Tube Voltmeter (VTVM) regularly employed these molded capacitors inside its AC voltage measurement input divider strings to handle high-voltage spikes during laboratory circuit diagnostics.
