"The 415E is a 1 kHz swr meter from Agilent. The standing wave ratio (SWR) meter, or voltage standing wave ratio (VSWR) meter, measures the SWR of a transmission line. Use an SWR meter to document and log the degree of mismatch between a transmission load, usually the radio antenna, and its line. SWR meters measure the effectiveness of a transmission’s impedance matching performance","Additional Features:","The Agilent HP 415E SWR Meter is a low noise, 1000 Hz tuned amplifier and voltmeter, calibrated in dB and SWR. Designed for use with square law detectors, it measures SWR< attenuation, and gain directly from metered scales, or drives an X-Y recorder for RF substitution measurements. Front panel INPUT switch selects unbiased low (50-200 Ohms) or high (2500-10,000 Ohms) impedance crystal, biased crystal (1 V into 1 kOhm), or low or high current bolometer (4.5 or 8.7 mA +- 3% INTO 200 Ohms).","An internal precision 60 dB attenuator allows the HP 415E to operate over a 70 dB range in 10 or 2 dB steps, with +- 0.05 dB accuracy for a 10 dB step; maximum cumulative error between any two 10 dB steps is +- .1 dB. Sensitivity is 0.15uV rms for full scale deflection at maximum bandwidth (1 uV rms on high impedance crystal input).","Continuously adjustable bandwidth can be adjusted from 15 Hz for maximum sensitivity at CW frequencies to 130 Hz for swept frequency uses. An optional rechargeable battery pack provides up to 36 hours of continuous operation for portable use."