Food thermometer for microwave oven

Apparatus for monitoring the internal temperature of food being cooked in the cooking cavity of a microwave oven with microwaves of a predetermined frequency having a predetermined wavelength .lambda., said apparatus comprising:

• a. temperature-sensing probe adapted for insertion into the food to be cooked, said probe including an elongated, conductive housing, the distal end of which is closed and shaped to facilitate insertion into the food and said probe further including a thermally-responsive electrical element positioned internally of the housing near the distal end;
• b. circuitry responsive to thermally-induced changes in a characteristic of said electrical element to produce a control effect indicative of the food temperature;
• and
• c. a flexible shielded cable connecting said electrical element to said circuitry, the cable shield being electrically connected at one end to said probe housing and at the other end to a wall of the cooking cavity, the total effective electrical length of said probe and said cable, measured along the cable and probe from said cavity wall to the distal end of said probe, being within the range of from about n .lambda./2 - .lambda./8 to n .lambda./2 + .lambda./8, where n is any integer, whereby in use the combination of said shielded cable and said probe is nonresonant at said predetermined wavelength .lambda. and said electrical element is completely shielded from microwave energy.