Abstract: The lower end of a hollow thermocouple well is removed and replaced by an end cap of a different thermocouple material than the well so that the junction between the end cap and the end portion of the well defines a radially activated thermocouple junction. A wire of the same material as the end cap is affixed to the end cap and electrical connections are made to the wire and to the well to provide a thermocouple output signal indicative of temperature measurement. In another embodiment two end caps are utilized at the end of the thermocouple well with the two end caps being of two dissimilar thermocouple elements and which have the necessary electrical connections made thereof to provide a thermocouple output signal.