A thermoresistive AC-DC transfer element

A thermoresistive ac-to-dc transfer device has been reduced to practice by using an indirectly heated sensing element having a high-temperature coefficient of resistance to determine the heating power of input signal. Precise ac-to-dc transfer measurements were made beyond 100 MHz over serverai octaves of square-law response. The thermoresistive transfer converter (TRC) is inexpensive to manufacture and is usable in conventional 200-Ω/V 5-mA systems. The TRC employs continuous contact of the sensing element along the heater and therefore presents an alternative to the multijunction thermal converter (MJTC) for improved precision ac metrology.