The 16085B 4-Terminal Pair to 7 mm (APC-7) adapter: Is it advisable to use fixture compensation standards or coaxial calibration standards?

The Keysight 16085B is a 4-terminal pair to 7 mm adapter. The 16085B interface at the instrument is a 4-termainal pair configuration and a 7 mm adapter at the fixture / device under test interface. The Keysight 16085B is designed to allow impedance test fixtures with 7 mm connections to mate to those low frequency LCR meters and Impedance analyzers (less than or equal to 110MHz) equipped with 4-terminal pair interfaces. For example, the Keysight 16085B allows a Keysight 16092A 7 mm based spring clip fixture to be utilized with a Keysight E4980A 4-terminal pair based LCR meter.

When combining the 16085B with a 7 mm coaxial test fixture such as the Keysight 16092A Spring Clip Fixture it is recommended the instruments basic open/short (or open/short/load - if required*) compensation be performed directly at the final test fixture. For this configuration 7 mm coaxial standards are not required. The residual impedance of the 16085B can be compensated for via the use of open/short (or open/short/load) compensation process.

If the application requires the device under test to be connected directly to the 7 mm launch of the 16085B, without the use of an additional fixture, then the following 7 mm open/short (and load – if required) coaxial standards can be utilized for open / short (and load) compensation:

• E4991-60021 or 04191-85300: 7 mm (APC-7) short standard
• E4991-60022 or 04191-85032: 7 mm (APC-7) open standard
• 16195A/B Calibration kit: 7 mm (APC-7) open, short and load standards
• 85031B Calibration kit: 7 mm (APC-7) open, short and load standards