A magnetron filter board for a microwave oven is disclosed. In embodiments, the magnetron filter board includes a printed circuit board with a first trace and a second trace on the printed circuit board. The first trace includes a first end for connecting to a magnetron and a second end for connecting to a power supply unit. The second trace also includes a first end for connecting to the magnetron and a second end for connecting to the power supply unit. The first trace and the second trace can be configured as a radio frequency band-gap filter that mitigates noise associated with the connection between the magnetron and the power supply unit.