LT103 Maury Microwave Coaxial Thermal Voltmeter

The Maury Microwave LT10x Series Coaxial Thermal Voltmeters are precision laboratory instruments for accurate voltage measurements. They are manufactured in six voltage ranges from 0.1 to 20.4 volts and are useful from DC to 100 MHz.

The Maury Microwave LT10x Series Coaxial Thermal Voltmeters are constructed in a coaxial in-line configuration. A uhf thermocouple (isolated heater type with a reversal error of 0.04% maximum), having minimum AC-DC differences, is used as the converter. The heater of the thermoelement is connected in series with a low reactance film type resistor which terminates in a G.R type 874-P858 coaxial input connector. The thermoelement junction output is via a two-pin AN3102-10SI-4P connector. Rigid coaxial mounting serves to positively maintain the mechanical position of both components as well as to provide shielding between circuits. The heavy case and high exterior reflectivity provide isolation from rapid thermal gradients.

The accuracy of Maury Microwave LT10x Series Coaxial Thermal Voltmeters are dependent only on two factors: (a) its AC-DC difference as certified by NIST and (b) the accuracy of DC reference voltage. Calibration of these instruments is normally not performed because the transfer technique is dependent only upon flatness of response with frequency change. DC is generally used as the comparison frequency because of the general availability of high accuracy DC instruments. Several advantages of a direct 1:1 transfer technique are (a) no periodic calibration required, (b) no calibration is lost in the event of thermocouple burn-out, (c) no allowance is necessary for drift, (d) no compensation for temperature change is necessary.