Bajaj 2504 ETC (25 Litre) Microwave Oven, grill Convection model25 Litre capacity Digital timer Easy jog dial for settings adjustment, A microwave oven is a relatively small, boxlike oven that raises the temperature of food by subjecting it to a high-frequency electromagnetic field. Microwave ovens generate radiation at a frequency of about 2,450 megahertz by means of a magnetron, which is a kind of electron tube.