The nearly final voltage measurement by [Double M Innovations]. A rather hefty 88 µF, 1200 V capacitor, a full bridge rectifier, and 73 meters (240 feet) of coax cable to a spot underneath the ...

One is laid bare by [WizardTim], as he cross-sections a 20KV high-voltage diode ... a relatively low maximum reverse voltage, for example with the 1N4001 rectifier it’s 50V.