The E4401B is a discontinued frequency range of the popular ESA-E spectrum analyzer series. Customers looking for a general purpose spectrum analyzer will appreciate the flexibility of the ESA-E spectrum that comes in four other frequency ranges. Customer who wish to take advantage of the ESA flexibility but who need a faster analyzer for the manufacturing line, or connectivity to LAN/USB in addition to GPIB, or want to do in –depth signal analysis with 89600 VSA software will benefit from the new EXA signal analyzer. The EXA signal analyzer now comes standard with many of the ESA’s optional features and yet offers more applications than the ESA.