Keysight 8720 Series Vector Network Analyzers

7 models with full specifications from Keysight Technologies (Agilent HP).

The Keysight Technologies (formerly Agilent / HP) 8720 series consists of high-performance microwave vector network analyzers (VNAs) designed for the thorough characterization of active and passive RF and microwave components. This family is suitable for engineering and manufacturing applications that require precise phase and magnitude measurements of transmission and reflection parameters. The series spans several generations, including the C, D, and ES configurations, and covers three distinct maximum frequency limits.

The family features a unified architecture that integrates a synthesized source, a switching S-parameter test set, and a tuned receiver into a single chassis. The instruments differ primarily in their frequency coverage, display technologies, internal storage media, and calibration options. This guide helps technical buyers and engineers choose between the 13.5 GHz 8719D, the 20 GHz models (8720C, 8720D, and 8720ES), and the high-frequency 40 GHz instruments (8722C, 8722D, and 8722ES).

Frequency Range
50 MHz to 40 GHz (model dependent)
Standard Impedance
50 Ω
Measurement Channels
2 independent channels
Standard Weight
25 kg (most models)

Models in this series

ModelTypeFrequency RangeDisplayFrequency Resolution
8720ESVector50 MHz to 20 GHzColor LCD1 Hz
8722ESVector50 MHz to 40 GHzColor LCD1 Hz
8722DMicrowave50 MHz to 40 GHzColor CRT1 Hz
8720DMicrowave50 MHz to 20 GHzColor CRT1 Hz
8720CVector50 MHz - 20 GHzLarge color display
8722CVector50 MHz to 40 GHz
8719DMicrowave50 MHz to 13.5 GHz1 Hz

Frequency Coverage and Interface Standards

The primary differentiator within the 8720 family is the maximum operating frequency, which also determines the physical test port interface standard:

  • 13.5 GHz Limits: The 8719D covers 50 MHz to 13.5 GHz and features a 3.5 mm male test port.
  • 20 GHz Limits: The 8720C, 8720D, and 8720ES operate from 50 MHz to 20 GHz. The 8720ES uses 3.5 mm male test port connectors.
  • 40 GHz Limits: The 8722C, 8722D, and 8722ES extend coverage up to 40 GHz to accommodate high-frequency millimeter-wave applications. The 8722ES is configured with 2.4 mm test ports.

Evolution of C, D, and ES Generations

The physical construction and internal capabilities evolved significantly across the product generations:

  • C Generation: Models like the 8720C and 8722C introduced early solid-state switching options for continuous S-parameter updates. The 8722C features a standard frequency resolution of 100 kHz (upgradeable to 1 Hz with Option 001) and includes options for a three-channel direct-access receiver (Option 011).
  • D Generation: The 8719D, 8720D, and 8722D models standardly integrated 1 Hz frequency resolution and color CRT displays. They also added an internal 3.5-inch MS-DOS compatible floppy disk drive for saving states and data.
  • ES Generation: The final iteration, represented by the 8720ES and 8722ES, upgraded the system display to a color LCD. These models support modern Electronic Calibration (ECal) compatibility and advanced calibration routines like adapter-removal and optional TRL.

Measurement Formats and Capabilities

Across all generations, these vector network analyzers measure a full set of S-parameters (S11, S21, S12, S22) with two independent measurement channels. Users can select from various sweep types, including linear frequency, logarithmic frequency, list frequency, and power sweeps.

Select models support specific hardware options to expand measurement flexibility. For instance, Option 010 adds time-domain transformation capabilities to the 8719D, 8722C, and 8722D. For applications requiring high frequency accuracy, Option 1D5 provides a high-stability frequency reference, available on models such as the 8719D, 8720D, and 8722C.

Frequently asked questions

Which models in this series support Electronic Calibration (ECal)?
The ES generation models, including the 8720ES and 8722ES, officially support Electronic Calibration (ECal) compatibility.
What display technology is used in the different generations?
The D generation analyzers, such as the 8720D and 8722D, utilize a color CRT display, while the newer ES models, like the 8720ES and 8722ES, are equipped with a color LCD.
What is the frequency resolution of these network analyzers?
Models in the D and ES series (such as the 8719D, 8720D, 8722D, and 8720ES) have a standard frequency resolution of 1 Hz. The older 8722C has a standard resolution of 100 kHz, which can be upgraded to 1 Hz with Option 001.