Follow all guidelines to prevent damage to instruments and connectors and to make the best possible measurements.

  • Tighten connectors without rotating the center pin.—Never tighten the connectors, adapters, or cables such that the center pin rotates.
  • Avoid touching connectors with bare hands.—Touching connectors can contaminate the connectors with natural skin oils and microscopic dirt particles. Natural skin oils and microscopic dirt particles are difficult to remove from connectors. Contaminated connectors can affect your measurements.
  • Observe the pin depth of mating connectors.—Mate the proper connectors with PXIe-5633 instruments. Before mating the connector with another device or cable, measure the pin depth of the device that you want to mate. To measure the pin depth, use a pin depth gauge. Improper pin depth of mating connectors is a major cause of failure in the field.
    Figure 5. Features of Mating Connectors


    1. Reference plane
    2. Female connector
    3. Male connector
    4. Pin depth

    The center pin of RF component connectors has a precision tolerance measured in mils (1/1000 in.). Connectors on test devices that mate with RF components might not be precision types and might not have the proper depth. To ensure suitability, measure the connectors before mating.

    Gauge the pin depth of the test device connector. If the pin depth measures outside the tolerances listed in the following table, the center pin is too long and can damage the termination connector:

    Port/Connector Type Pin Depth Gauge Setting
    3.5 mm (m), 3.5 mm (f)

    -0.0002 in.

    -0.0007 in.

    		 Same as pin depth
    2.92 mm (m), 2.92 mm (f)

    -0.0002 in.

    -0.0007 in.

    		 Same as pin depth
    1.85 mm (m), 1.85 mm (f)

    -0.0002 in.

    -0.0010 in.

    		 Same as pin depth

    If the test device connector measures out of tolerance in the "-" region, the center pin is too short. While this connection does not cause damage, it results in a poor connection and consequent performance degradation.

  • Avoid lateral pressure.—Never put lateral pressure on the center pin of the connector.
  • Always torque connectors to the specified torque using a torque wrench.—Do not over-tighten connectors. Over-tightening might damage the connector center pin. Always use a 0.9 N · m (8 in. · lb) torque wrench when tightening 1.85 mm, 2.92 mm, 3.5 mm, and SMA connectors for PXIe-5633 instruments. Always tighten to the torque specified in this manual.
  • Do not disturb Teflon tuning washers.—The center conductor on some RF components contains a small Teflon tuning washer that compensates for minor impedance discontinuities at the interface. The washer location is critical to the RF component performance.
    Notice Do not disturb the Teflon tuning washer in connectors.
  • Avoid mechanical shock.—Precision connectors are designed to withstand years of normal bench handling. Handle the connectors carefully. Mechanical shock significantly reduces the service life of the connectors.
  • Avoid applying excessive power.—Test instrumentation is rated for a specific maximum continuous input power. Exceeding the maximum input power level permanently damages the internal components. Refer to the safety, environmental, and regulatory information document or the instrument specifications for these levels.
  • Protect connectors when not in use.—Cover connectors that are not in use with the dust cap included with your instrument.