Hewlett-Packard 3455A

The HP3455A digital voltmeter is a microprocessor controlled 51/2 0r 61/2 digit integrating voltmeter for bench or system applications. The standard instrument measures DC volts, AC volts, and resistance. HP-IB and auto or manual ranging also come standard. Accuracy is ±0.0008% + 2 counts on the 10DCV range over a 24 hour period.

Hewlett-Packard 3457A

The HP3457A digital multi-meter has versatility, functionality and dependability. It has seven functions with 31/2 to 61/2 digits of resolution extendible to 71/2 digits at reading rates from 1 reading per every 2 seconds to 1350 readings/sec and DC volts accuracy as high as 5ppm. In addition, the input of the HP3457A can be expanded up to ten channels with either of the optional plug in multiplexer assemblies (sold separately). This unit measures DC volts & current, resistance, true RMS AC volts & current, frequency, and period. It also performs the following main functions: Null; Scale; Offset; RMS filter; Single pole filter; Thermistor Linearization; dB, dBm, % Error; and Pass/Fail limit Testing.