These cards permit monitoring of up to nine thermocouples or other transducers. The nine signal channels use a guarded 2-pole configuration. An isothermal block provides electrical isolation up to 42V while assuring excellent thermal conductivity between cold junction terminations. A sensing device mounted in the isothermal block monitors the cold junction and outputs a calibrated reference voltage that is linearly related to the temperature. The Model 7057A provides a higher change in reference output for improved cold junction sensitivity. Formulae for converting the voltage outputs of all of the most popular thermocouple types are included in the manual. The contact potential of <1μV per channel translates to <0.025°C error for precision measurements on type K thermocouples.