Universal-serial-bus (USB) devices, such as memory cards, printers, and scanners, have certainly simplified connection of peripheral equipment to laptop and desktop computers. The USB interface is also beginning to make an impact on electronic test and measurement equipment, with the growing availability of USB-compatible high-frequency test equipment, notably power meters. A story below details a new family of USB test instruments from Agilent Technologies, including several digital sampling oscilloscopes and a function generator.
The simplicity of a USB instrument is appealing. Simply plug the instrument into an available USB port on a laptop or desktop personal computer and, once the device is recognized by the computer, use the appropriate software and the computer as the user interface. The USB interface provides a great deal of flexibility in placing the computer display near the device under test (DUT), with USB supporting cable lengths as long as 5 m between the DUT and the computer. The small size of most USB instruments allows them to be positioned in close proximity to the DUT.
The USB interface may not be appropriate for all high-frequency instruments, such as vector network analyzers, but for instruments such as oscilloscopes, voltmeters, and power meters that can leverage the processing power of a personal computer, this is a match of technologies that makes perfect sense.