The tx-dmm family of handheld True rms digital multimeters (dmms) features simultaneous reading of AC and DC measurements using dual numeric displays. Both the TX1 and TX3 models use digital rms for high- resolution AC measurements with instantaneous settling time. The TX3 version provides 0.05% DC accuracy and 50,000-count resolution and has a built-in digital thermometer and 4- to 20-milliampere process loop measurements. It offers 30 memory locations, allowing users to store data for tracking and documenting field measurements. The TX1 model stores data in 10 memory locations. All tx-dmm multimeters provide an electronic readout of the last calibration date and come standard with a traceable calibration certificate. Also available is the wstrm pc interface package, which includes the PC interface cable and WaveStar for Meters software, a Windows 95/NT application. The software enables data acquisition and real-time data logging from the dmm directly onto the PC. The TX1 and TX3 models cost $275 and $325, respectively. The optional wstrm pc interface is priced at $149.