Running internal adjustments

To optimize the accuracy for the application with the R&S SZU, you can execute calibration routines directly in the R&S SMW.

When to perform the internal adjustments?

We recommend that you perform the internal adjustment:

  • When setting up an application the first time.

  • When changing the I/Q output type of an already set measurement.

    When you have calibrated the R&S SZU with a different I/Q output type (single-ended / differential), the R&S SMW issues the notification:

    SZU settings conflict: At least one adjustment has been done in another mode than the SZU is currently set to (single-ended / differential). Accuracy may be affected!

To validate the setup before starting the adjustment
  1. Make sure that the serial number of the R&S SZU and the cable set match.

    The R&S SZU is calibrated with the supplied cables. Other cables lead to deviations from the specified values and thus affect the adjustment accuracy.

  2. Connect the R&S SZU to the R&S SMW as described in "Setting up the measurement".

  3. Remove the protective cap from the waveguide port, if plugged.

    The protective cap plugged on the waveguide port can cause undefined reflections, and thus impact the internal adjustments.

  4. Make sure that you have terminated the waveguide port properly, see "Cable selection and electromagnetic interference (EMI)".

  5. Make sure that no power is fed into the waveguide output during the internal adjustment process.

    It can be caused, e.g. by a connected spectrum analyzer which emits LO power when operating in receiving mode.

To adjust the R&S SZU
  1. In the R&S SMW, configure the R&S SZU.

    See "To configure the R&S SZU in the R&S SMW".

  2. Make sure, that you have selected the correct I/Q output type (single ended or differential).

  3. Check the connection with the connection test in the R&S SMW.

    See "To configure the R&S SZU in the R&S SMW" > step 6.

  4. In the R&S SMW, select System Config > Setup > General > Internal Adjustments.

    In this dialog you can perform the internal calibration routine for the R&S SZU, when connected.

    The R&S SMW adjusts the internal calibration routines to the R&S SZU. Adjust All is disabled, i.e. in this configuration, you cannot execute adjustment routines for the R&S SMW.

  5. Select Adjust External Frequency Converter A/B for all R&S SZU.

    The R&S SMW automatically calibrates the parameters of the externally connected R&S SZU.

  6. When completed, check that no errors occurred.

    If the internal adjustments detect any errors, see User Manual of R&S SMW, chapter Internal Adjustment Settings for further information on how to proceed.