The 305PA3009 Wideband Network Analyzer Plug-In (Gain/Phase/Amplitude) is designed for use with any 305 Phasemeter Mainframe. The unit measures the voltage amplitude of each signal input (in volts or dBV, selectable by operator), the phase difference between inputs, and the amplitude ratio of inputs (dB). Featuring auto-ranging of gain in both channels, it requires no manual setting of gains for any measurement. Simultaneous DC outputs on mainframe are proportional to all four functions. A front-panel switch selects the measuring mode for digital panel readout of channel A voltage, channel B voltage, phase difference, or amplitude ratio. Lamps on the front panel of the unit indicate the proper decade multiplier. Input level range of 10 mV rms to 40 V rms, 5Hz to 700kHz, both inputs. 1 Mohm inputs.