secondary standard

Definitions

Electronics

  • A unit which is a specified multiple of a primary standard (1). For example, a nanosecond, which is 10-9 second.
  • A reference which has been determined with very high accuracy, but which must be calibrated or otherwise verified by a primary standard (2). Such a secondary standard may be adequate for many applications, and might itself be used as a reference for other devices and instruments.
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