Abstract: A wireless bar code reader, which simplifies the setting and operation of a microwave oven, comprises a scanning unit for reading bar codes in a cookbook and a transmitting unit for transmitting to the control unit of the microwave oven a bar code signal indicative of the information related to the bar code read by the scanning unit. A secondary battery serves as its power source and a jack for charging it is disposed on the same side of the reader as the scanning unit. The transmitting unit is disposed at the opposite end. The reading and transmitting units are either in both perpendicular and parallel directivity relationship or simply in perpendicular relationship to each other.

Abstract: A heating appliance includes a heating chamber for accommodating a food to be heated and a casing carrying the food, a weight measuring device for measuring a tare weight of the casing and a gross weight of the casing and the food disposed in the heating chamber, a calculation circuit for calculating a net weight of the food in response to the output of the weight measuring device, a first display for displaying the net weight of the food, and a second display for displaying the gross weight of the casing and the food.