N7812A Test Equipment

This topic shows the equipment required to run the performance verification and adjustment tests. Some tests (for example Flatness) can use various model numbers of a particular equipment type. The Recommended Model will provide the best results. However, the Alternative Model is an acceptable substitute.

Not all of the listed test equipment needs to be connected to perform an individual test. To run a test, only the equipment specified for that test needs to be connected.

The validity of performance verification and adjustment measurements depend in part on the accuracy of the required test equipment. Verify proper calibration of test equipment before running tests with this software.

The following sections are included in this topic:

• Required Test Equipment

• Power Sensor & Power Meter Calibration & Zeroing Operation

• Self Alignment

• Warmup Times

• Calibration Data Validation

• Test Plan Specific Checks

Required Test Equipment

Table Footnotes

1. E8257D with Options 1EA/1EU, 1E1, 007, and UNX or UNR or UNY can be used as RF Source #1, RF Source #2, and RF Source #5.

2. N1914A power meters with serial number prefix prior to MY53040007 require Service Note N1914A-07 which fixes a power supply ground loop. The ground loop injects noise into the measurement circuits which can cause unstable measurements at low (–30 dBm) power levels

3. The step attenuators should be permanently joined via the 11716A Interconnect Kit as shown in the diagram.

   

   Step Attenuator Loss Characterization

   The step attenuator combination should have each attenuator setting characterized by a metrology lab at 50 MHz. The following tables show which sections of the 10 dB and 1 dB step attenuators are utilized for each attenuator setting. The tables also list the Allowable Uncertainty for each attenuator setting.

   The interconnect cable should NEVER be disconnected once the loss characterization is performed.

   1 dB Step Attenuator

   Nominal Attenuation (dB)	Attenuator Section				Recommended Uncertainty (dB)
   	#1 (1 dB)	#2 (2 dB)	#3 (4 dB)	#4 (4 dB)
   0	Off	Off	Off	Off	0 (Reference)
   1	On	Off	Off	Off	< 0.005
   2	Off	On	Off	Off	< 0.005
   3	On	On	Off	Off	< 0.005
   4	Off	Off	Ona	Off	< 0.005
   5	On	Off	On	Off	< 0.005
   6	Off	On	On	Off	< 0.005
   7	On	On	On	Off	< 0.005
   8	Off	Off	On	On	< 0.005
   9	On	Off	On	On	< 0.005
   10	Off	On	On	On	< 0.010
   11	On	On	On	On	< 0.010

   1. TME requires that Section 3 be characterized.

    

   10 dB Step Attenuator

   Nominal Attenuation (dB)	Attenuator Section				Recommended Uncertainty (dB)
   	#1 (10 dB)	#2 (20 dB)	#3 (40 dB)	#4 (40 dB)
   0	Off	Off	Off	Off	0 (Reference)
   10	On	Off	Off	Off	< 0.010
   20	Off	On	Off	Off	< 0.015
   30	On	On	Off	Off	< 0.020
   40	Off	Off	Ona	Off	< 0.025
   50	On	Off	On	Off	< 0.030
   60	Off	On	On	Off	< 0.035
   70	On	On	On	Off	< 0.040
   80	Off	Off	On	On	< 0.046
   90	On	Off	On	On	< 0.055
   100	Off	On	On	On	< 0.058
   110	On	On	On	On	< 0.064

   1. TME requires that Section 3 be characterized.

Guidelines for Ordering Power-Sensor Calibration Service

Use the following guidelines to ensure power sensors used by the N7800A application receive the correct calibration service:

1. Order Option 1A7 when ordering new power sensors that will be used as working standards in N7800A TME calibrations.

2. In the Americas region, order the Keysight Cal + Measurement Uncertainty for power sensor recalibration.

3. Outside the Americas region, order ISO 17025/ILAC-G8 calibration service for power sensor recalibration.

4. When ordering periodic calibration for instruments used as lab standards in the N7800A software, we recommend using “Keysight calibration + uncertainties” for power sensors, and “Keysight calibration + uncertainties + guardbanding” for all other items (please visit Selecting the Right Calibration Services). The N7800A software incorporates the GUM = The Guide to the Expression of Uncertainty in MeasurementISO GUM Uncertainty in point-to-point uncertainty calculations. The special “H-series” calibration options in this table provide lower measurement uncertainties through use of direct comparison to devices directly characterized by NPL = National Physical LibraryNPL or NIST = National Institute of Standards and TechnologyNIST (or another NMI = National Measurement InstituteNMI). Please order Option H99 to get data on a CD for easy import into the N7800A (avoids manual entry). The overall resulting N7800A measurement uncertainties then reflects these lower device uncertainties. The equipment requirements of each N7800A calibration application are summarized in the specials calibration matrix which can be found at the Recommended Lab Standards and Special Cal Options website.

5. The Keysight Option H99 is a special option for the Roseville Service Center [only] which provides a CD with calibration data included as a .csv file in TME N7800A format for all power sensors used with the N7800A TME application. N7800A TME is SSU calibration software used across Keysight SSU and by many self-maintainers. H99 must be requested from the Roseville SSU upon re-calibration only of any previously purchased power sensor and not for new purchases of BID Power Sensors. This option provides for adding the calibration data to a CD and may be ordered in addition to any other required or requested Std Lab Calibration option (must also be ordered in addition to H99). Option H99 is recommended but not required.

   The following models are not supported by Option H99 (calibration data on a CD in .csv format): E9304A-H18 E9304A-H19 E9304A-H84 E9400A-H25 N8486AQ N8486A

Power Sensor & Power Meter Calibration & Zeroing Operation

The calibration and zeroing operation of a power sensor and power meter are done automatically by the software. Each operation is valid for 2 hours.

When a power sensor is needed for a given test, you will be asked to connect it to the appropriate power meter channel and POWER REF input in order to do the calibration and zeroing operation. The time stamp of the operation is then logged based on the serial numbers. The next time that a test requires the use of these two pieces of equipment, the last operation time stamp (if one exists) is checked to determine if a new calibration and zeroing operation is needed.

Self Alignment

A self -alignment procedure is automatically run when the E4406A VSA is turned on. The instrument will automatically run a new self-alignment procedure when 24 hours have elapsed.

When a test requires a self alignment, it will run it. The time stamp of the procedure is then logged based on the instrument serial number. When another test requires a self alignment, it first checks the last self-alignment time stamp to determine if a new procedure is needed.

Warmup Times

Please allow sufficient warmup time for the test equipment. Refer to the specified operating temperature range.

• For the E4406A VSA, minimum warmup time is at least two hours. Some adjustments may require 24 hours.

• For test equipment, refer to individual operating and service manuals for warmup specifications.

Calibration Data Validation

Standard Checks

To ensure data integrity for measurements carried out with TME (Test Management Environment), the following verification checks are carried out at the beginning of each test run. The checks are only performed on devices that require calibration data which directly affect the test results.

The following table lists the standard checks performed by default:

Test Plan Specific Checks

In addition to the standard checks carried out, the following additional limits affecting measurement uncertainty are verified for the E4406A VSA performance verification test plan.

Power Sensors

Step Attenuators