Isolator

This is a device designed to protect the oscillator from reflected microwaves. If the microwave irradiation to the load (the heating target) is inappropriate, or if the load is inherently difficult to absorb microwaves, the unabsorbed microwaves can return to the oscillator side as reflected waves, causing reverse heating of the magnetron and potentially damaging it. To prevent this, an isolator bends the reflected waves towards the dummy load, allowing them to be absorbed by the dummy load. There are two types: air-cooled and water-cooled.