Frequency Response 300 kHz to 3 GHz Performance Test

Frequency Response (or flatness) is defined as the amplitude deviation from the reference value at 50 MHz. The complete E444XA Frequency Response is measured with three different tests:

The Frequency Response Below 300 kHz test is used to verify flatness from 10 Hz to 300 kHz. The 300 kHz normalized error from the Frequency Response 300 kHz to 3 GHz test is used as the reference point for the Frequency Response Below 300 kHz test.

The Frequency Response Above 3 GHz test verifies flatness from 3.0 GHz up to 50 GHz, depending on your instrument frequency range.

This test measures Frequency Response 300 kHz to 3.0 GHz with the preamplifier (Option 1DS or Option 110) off and on, in AC coupled mode, and with 10, 20, 30, and 40 dB of attenuation. For each test frequency, the amplitude error is normalized to 50 MHz, and the result is called Frequency Response.

This test has three sections. The first section measures the flatness from 300 kHz to 3 GHz with the preamplifier turned off and 10 dB of RF attenuation. This section will characterize the tracking error of the 11667A power splitter in order to reduce measurement uncertainties.

The second section measures flatness from 50 MHz to 3 GHz with 20, 30, and 40 dB of RF attenuation (preamplifier is off). This section is performed on instruments with Serial Number Prefixes greater than US4251, or MY4251. As with the first section, the splitter tracking will be characterized in an effort to reduce the measurement uncertainties.

The third section measures flatness from 300 kHz to 3 GHz with the preamplifier turned on. As with the first section, the splitter tracking will be characterized in an effort to reduce the measurement uncertainties.

For instruments with Option 122 or 140 (Wideband IF) this test measures flatness from 50 MHz to 3 GHz.

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Required Test Equipment

Test Equipment

Model Number

Signal Source

PSG Models
(see equipment list)

Power Meter

N1914B

Power Sensor
(2 required)

N8482A

20 dB Attenuator 
(for Option 1DS only)

8491A/B Opt 020

Power Splitter

11667A 

Type-N Cable

11500C

BNC Cable

8120-2582

Type-N (m) to Type-N (m) adapter

1250-1475

Type-N (m) to 3.5 mm (f) adapter
(for E4440A/43A/45A Option BAB)

1250-1744

2.4 mm (f) to Type-N (m) adapter
(for E4446A/47A/48A)

11903D

Connection Setups

Power Meter Calibration (Channel A)

Power Meter Calibration (Channel B)

300 kHz to 3 GHz Splitter Calibration

300 kHz to 3 GHz Flatness Test Setup

300 kHz to 3 GHz Splitter Calibration
(Preamp on, Opt 1DS or 110 only)

300 kHz to 3 GHz Flatness Test Setup
(Preamp on, Opt 1DS or 110 only)