Deadly high voltage levels in microwave oven. HV transformer has two secondary windings (shown as two transformers in simulation) of low voltage 3.2 volts to heat cathode of Magnetron and high voltage 5000 to 6000 volts out of capacitor and diode voltage doubling circuit below.
Upper circuit with SPST represents heater of Magnetron and NC represents anode of Magnetron connected to ground.
Caution on safety measures and avoiding wiring and other mistakes is stressed in "Microwave Oven Repair" by Humphrey Kimathi. When electrocution is at stake - making mistakes and what never to test matters.