R&S®ESR3

The R&S ESR3 is a full-featured benchtop EMI test receiver covering 9 kHz to 3.6 GHz on its primary input and 9 kHz to 1 GHz on a dedicated second input — both DC coupled. It operates in EMI receiver, spectrum analyzer, and optionally real-time spectrum analyzer modes, with the preselection network permanently engaged in receiver mode across sixteen fixed-bandwidth filters spanning the full frequency range. A switchable 20 dB preamplifier (1 kHz–7 GHz signal path) improves sensitivity when needed; an optional low-noise amplifier (FSV-B22) is also available for the ESR3 and ESR7 variants.

In receiver mode the ESR3 supports up to four simultaneous detectors — positive peak, negative peak, RMS, average, quasi-peak, CISPR-average, and RMS-average — with individual analog bargraph displays per detector and 0.01 dB digital readout resolution. CISPR detector performance is warranted in line with CISPR 16-1-1:2019 (Ed. 5.0) for all four EMI detector types. Absolute level uncertainty at 64 MHz is less than 0.2 dB (preselection off, +20 °C to +30 °C), and total measurement uncertainty from 10 MHz to 3.6 GHz is 0.29 dB at 95% confidence. The optional ESR-B50 hardware board unlocks both the K53 time domain scan and K55 real-time analysis software keys; with K53 fitted, the ESR3 can process segments up to 30 MHz wide in parallel below 7 GHz at 9 kHz RBW.