Keysight Technologies (Agilent HP) Coaxial Hardware

Keysight's step attenuators are categorized by their actuation method and frequency range. Manual step attenuators, such as the 8494A (DC to 4 GHz, 1 dB steps) and the 8495B or 8496B (DC to 18 GHz, 10 dB steps), feature direct-reading dials and manual control knobs. These manual units are suited for benchtop operations where automated adjustment is not required.

For automated test setups, programmable step attenuators like the 8494G (DC to 4 GHz) and the 8495H (DC to 18 GHz) utilize magnetic-latching solenoids. These devices offer high repeatability, typically 0.01 dB, and have a specified switching life exceeding 5 million cycles per section. They operate with standard supply voltage options including 5 Vdc, 15 Vdc, and 24 Vdc.

For applications requiring precise attenuation above 18 GHz, Keysight provides high-frequency step attenuators utilizing thin-film tantalum nitride attenuation cards on sapphire substrates. Models such as the 84904K and 84907K operate from DC to 26.5 GHz, while the 84904L and 84906L extend the range up to 40 GHz. These high-frequency attenuators feature 2.4 mm or 3.5 mm RF connectors and are designed for integration into automated test equipment (ATE) systems, offering maximum SWR values of 1.7 to 1.8 at high frequencies.

Keysight's fixed coaxial attenuators provide stable attenuation and flat frequency response. The 8491A (DC to 12.4 GHz) and 8491B (DC to 18 GHz) utilize Type-N connectors, while the 8493C offers APC-3.5 connectors up to 26.5 GHz. For high-frequency millimeter-wave setups, the 8490D provides fixed attenuation up to 50 GHz with 2.4 mm connectors.

For signal level monitoring, the 85025D is a coaxial detector operating from 10 MHz to 50 GHz. It supports both AC (modulated) and DC (unmodulated) detection modes when connected to compatible network analyzers.

Keysight designs signal routing components to minimize measurement uncertainty. Dual-directional couplers, such as the 778D (100 MHz to 2 GHz) and the 11692D (2 to 18 GHz), allow simultaneous characterization of reflection and transmission. For wideband ratio measurements and source leveling, two-resistor power splitters like the 11667A (DC to 18 GHz) and 11667B (DC to 26.5 GHz) provide precise amplitude tracking.

To automate these components, the 11713B and 11713C attenuator and switch drivers provide front-panel manual override and remote GPIB, USB, and LAN interfaces. The 11713B controls up to two coaxial attenuators and two switches, while the 11713C controls up to four programmable attenuators and four switches.