现货HP/AGILENT 4937A三台.欢迎来电咨询!The HP4937A contains a set of voiceband transmission tests -- level/frequency measurement, noise, and 2- and 4-wire return loss measurements. It also has the ability to seize and hold three types of E/M lines. In addition, the HP 4937A simulates signaling both from the central office and from the PBX at the network interface.