Figure 1-65. Hewlett-Packard, Model 400EL, Voltmeter.
Hewlett-Packard, Model 400EL, Voltmeter (fig. 1-65) is used for measuring voltages from 1 mV to 300 V rms full scale.
Model 400EL covers a frequency range from 10 Hz to 10 MHz and has a constant 10-megohm input resistance on all
ranges. Input capacitance less than 25 pF on the 1-mV to I-V range and less than 12 pF on the 3 to 300 V range. Model
400EL gives direct voltage and dBm readings.