Display Scale Fidelity Performance Test

This test verifies the scale fidelity (linearity) of the analyzer at 50 MHz by comparing it to an external precision attenuator. As the external attenuation is increased in steps, the change in power level indicated by the analyzer's display-marker is monitored. This test is performed in two parts so the step attenuator uncertainties are minimized.

Part 1 — Input Mixer level of –21 dBm to –75 dBm

The analyzer input attenuator is set to 10 dB in zero-span mode. The source is set to +10 dBm and the external composite attenuator is set to 19 dB. The resulting –25 dBm signal is measured by the analyzer and recorded as the reference. The analyzer input power is then varied between –11 dBm and –65 dBm (–21 dBm to –75 dBm at the mixer) by switching the external attenuator.

Part 2 — Input Mixer level of –35 dBm to –16 dBm

The analyzer input attenuator is set to 10 dB in zero-span mode. The source is set to +10 dBm and the external composite attenuator is set to 26 dB. The resulting –25 dBm signal is measured by the analyzer and recorded as the reference. The input power is then varied between the –25 dBm and –6 dBm (–35 dBm to –16 dBm at the mixer) by switching the external attenuator.

This test requires step attenuator calibration data to obtain valid results. Make sure you enter the calibration data for the step attenuators that you're using. Please refer to the Enter Equipment Calibration Data section in the TME Help for details on how to enter this data. You must enter the data for the following columns to obtain valid results: Attn(dB), Uncert(dB), and ReflSize.

Required Test Equipment

Test Equipment

Recommended Model Number1

Microwave signal generator #1

PSG models
(see main equipment list)

Attenuator, 10 dB fixed

8491A Options 010, H33

Attenuator, 6 dB fixed

8491A Options 006, H33

Attenuator, 3 dB fixed

8491A Option 003

Attenuator, 10 dB step

8496G Options 001, H50

Attenuator, 1 dB step

8494G Options 001, H50

Attenuator driver

11713B

Attenuator interconnect kit

11716A

Cable, Type-N (m) to Type-N (m)

  • 2 required

11500C

Cable, BNC (m) to SMB (f)

8121-2063

Cable, Viking
(for attenuator control)

8120-2703

Adapter, 3.5 mm (f) to Type-N (f)

  • For 3.5 mm source

1250-1745

Adapter, 2.4 mm (f) to Type-N (f)

  • For 2.4 mm source

11903B

Adapter, 3.5 mm (m) to Type-N (f)

1250-1750
  1. Refer to the main equipment list for a list of alternative models (if available).

Connection Setups

Display Scale Fidelity Test Setup, Part 1

Display Scale Fidelity Test Setup, Part 2