A high voltage power supply for use in small diameter spaces such as in oil well logging devices includes an AC voltage source and a voltage multiplier circuit. An inside set of parallel capacitors is constructed with an inside common capacitor electrode, an inside dielectric material around the outside of the inside common capacitor electrode, and individual inside capacitor electrodes formed of conductive material positioned around the outside of the inside dielectric material. An outside set of parallel capacitors is constructed with a hollow outside common capacitor electrode with a central internal hollow space, an outside dielectric material around the inside of the outside common capacitor electrode, and individual outside capacitor electrodes formed of conductive material positioned around the inside of the outside dielectric material. The inside set of parallel capacitors fits concentrically inside the outside set of parallel capacitors. Rectifiers connect selected inside capacitors to selected outside capacitors to form a voltage multiplier circuit.