N7841A Required Test Equipment (all models)

This section lists the test equipment required to run tests, adjustments, and utilities. Models for each test equipment category are given in order of preference. Alternate or substitute models are listed after the preferred model, but should be considered as a lower priority. Refer to each individual test for specific setup configurations with required cables and adapters.

In addition to the equipment listed below, the following equipment is recommended when testing the FieldFox analyzer:

• Optimized Test Station — Required for N995xA, N996xA, N991xB, N993xB. See Optimized Test Station for more information.

• Main battery — Required if the analyzer is returned for service without a battery (P/N 1420-0891).

• USB flash drive — Used for firmware upgrades, option installation, etc. Also known as a USB memory stick. Must be 128 MB or larger.

• Small, free-standing fan — Used to cool the analyzer if internal temperature is too high. A small office fan of approximately six inches in diameter is sufficient. Refer to the Warm-up Procedures section for more information about internal temperature range.

• External power supply — Keysight part number 0950-5014

Table Footnotes:

1. Keysight, Agilent, or Hewlett-Packard model numbers unless otherwise noted.

2. A = Adjustments, T = Tests, U = Utilities

3. Supported PSG models:

   E8257D
   E8257C
   E8257N Option 340 (not for N9912A/23A/5xA/6xA)
   E8267C
   E8267D
   E8247C (for N9912A and N9923A only)

   One PSG with options 550, 1EA/1EU, 1E1, and [UNX or UNR or UNY] can be used as Microwave Signal Generator #1. The E8257N also requires the 2.4 mm (m) Aeroflex Weinschel Crown, part #7005A-13.

4. N1914A power meters with serial number prefix prior to MY5304007 require Service Note N1914A-07 with 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.

5. Random timeouts may occur with the E4419A power meter and the N-Series power sensor combination (for example, N8485A). If a timeout is encountered, then use one of the other power meter models listed in the Required Test Equipment list above.

6. The 8482A power sensor uses cal factors to compensate the power sensor for frequency response errors. Cal factors are stated in percentages. The 8482A factory cal factor uncertainty ranges from 2.2% to 3.1%. The cal factor uncertainty can be reduced to < 1.0% by using metrology grade calibration techniques. The power sensor cal factor uncertainty becomes one component of the Verification Test uncertainty analysis. Lower cal factor uncertainties will translate to wider test margins.

7. When using the 10 MHz External Reference, be sure to update the Additional Properties in TME to the correct Frequency Accuracy in parts per million (ppm). For example, if overall accuracy is 9e-12, the equivalent is 9e-6 ppm. Refer to the Additional Properties section in the N7800A TME Help for instructions.

8. 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. This characterization can be ordered through Keysight Technologies as an Option H50 Calibration.

   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 Recommended Uncertainty for each attenuator setting. A larger number will result in larger overall test uncertainties which could affect the test pass/fail rate.

   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 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

    

   aTME requires that Section 3 be characterized.

9. 8491A Option H33 is a fixed attenuator which has been characterized to have a VSWR ≤ 1.05:1 at 50 MHz. A VSWR of 1.05:1 is recommended for the Absolute Amplitude Accuracy performance test. Any 8491A/B attenuator can be mapped into this device if the VSWR at 50 MHz has been characterized to be ≤ 1.05:1. When mapping the attenuator to indicate that it meets the required specification, the Option H33 checkbox will need to be checked in the configure test station Administration screen.

10. The H01/H03 calibration kits are characterized device (CD) kits with unique, precision characterization data for each short, open, and load.

11. See ECal Troubleshooting for information about entering the correct ECal serial number in TME.

12. Refer to the GPS Function test page for information on alternate GPS signal sources.

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. When ordering periodic calibration for instruments used as lab standards in the N7800A software, we recommend using “Keysight Cal + Uncertainties + Guardbanding”. More information can be found at http://www.keysight.com/find/americas_cal.

3. 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 (shown on the Special Calibrations Matrix located at http://cal.software.keysight.com) 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). The overall resulting N7800A measurement uncertainties then reflects these lower device uncertainties. The equipment requirements of each N7800A calibration application are summarized in the Special Calibrations Matrix which can be found at http://cal.software.keysight.com.

4. Option H99 is a special option for the Roseville Service Center [only] which provides electronic calibration data available as a .csv file that can be imported into TME thus avoiding manual entry. Option H99 must be requested from the Roseville Service Center upon re-calibration only of any previously purchased power sensor and not for new purchases of power sensors. This option may be ordered in addition to any other required or requested Std Lab Calibration option. Option H99 is recommended but not required.

   The following models are not supported by Option H99: E9304A-H18, H19, H84 E9300A-H25 N8386A N8486AQ

Calibration Data Validation

Standards Checks

To ensure measurement data integrity within the TME (Test Management Environment), the following verification checks are performed at the beginning of each test run. The checks are only implemented on devices that require calibration data which directly affect the test results. If you are unable to meet the calibration requirements for these devices, you may still produce valid reports using the standard report format option which does not contain any measurement uncertainty information.

The following table lists the standards checks performed by default.