Meeting ISO 17025 Requirements for Complex Electronic Test Equipment

Hardly anything seems to be as confusing as interpreting ISO/IEC 17025 compliance forcomplex electronic test equipment (M&TE). The difficulty of the measurement uncertaintyanalysis for modern M&TE adds an additional impediment to the task of comparing themanufacturer's specifications to evaluation of available calibration services. This is essential to meeting the "Challenge of Measurement Interoperability." Calculating measurement uncertainties for a single parameter such as DC voltage is relatively straight forward, but to do so for a complex microwave spectrum analyzer that relies on digital signal processing is another matter. Accreditation was originally intended to provide a common denominator to compare quality of calibration services between one laboratory and another. Yet, the implementation of accreditation prevents a simple yes or no answer to the question: "does the instrument meet manufacturer's specifications?" Rather, the purchaser of accredited calibration services must evaluate a laboratory's scope of accreditation against the manufacturer's product specifications, which is not a simple matter for some derived parameters. This paper will explore the ways in which one equipment manufacturer, Agilent Technologies, is approaching in pragmatic and cost effective ways the balance between a metro logically correct ISO 17025 calibration and the needs of the equipment end user.