The HP 4194A Impedance/Gain-Phase Analyzer is an integrated solution for efficient measurement and analysis or go/no-go testing of components and circuits. The instrument provides detailed impedance and transmission characteristics, including secondary parameter derivations, that can be simply and quickly evaluated or tested. The companion HP 4192A LF Impedance Analyzer covers the lower-frequency range from 5 Hz to 13 MHz and supports both floating and grounded device measurements with standard GPIB connectivity.

An impedance analyzer measures the complex impedance of components and networks as a function of frequency, revealing how inductors, capacitors, resistors, and more complex devices behave under AC excitation. Engineers use these instruments to characterize passive components, verify component models, test materials, and evaluate circuit networks across a defined frequency span. The HP 4194A and HP 4192A address this measurement need across a combined frequency span from 5 Hz to 100 MHz, with the HP 4194A adding gain-phase transmission measurement capability for two-port network analysis.

Every impedance analyzer ValueTronics sells passes through our 20,000 square foot secure warehouse at 1675 Cambridge Drive in Elgin, Illinois, where our technicians physically inspect, power-test, and verify the instrument before it ships. This in-house verification is what separates a ValueTronics-graded analyzer from a pass-through broker listing, and it is why labs that need a known-condition impedance analyzer — not a description and a hope — have been calling Elgin for over three decades.

Brand Heritage

Hewlett-Packard's test and measurement business was spun out as Agilent Technologies in 1999, and Agilent's electronic measurement division then became Keysight Technologies in 2014. Instruments originally marketed under the HP brand, including the HP 4194A and HP 4192A impedance analyzers, trace their direct lineage through Agilent to today's Keysight product portfolio.

Compare Other Models in This Series

This page covers two HP impedance analyzers that together span the low-frequency through mid-frequency impedance measurement range: the HP 4192A LF Impedance Analyzer and the HP 4194A Impedance/Gain-Phase Analyzer. The HP 4192A is a dedicated impedance analyzer optimized for the 5 Hz to 13 MHz region, while the HP 4194A combines a wider 100 Hz to 40 MHz impedance measurement capability with a 10 Hz to 100 MHz gain-phase transmission measurement function in a single instrument.

Both analyzers share the standard impedance parameter set (|Z|, |Y|, θ, R, X, G, B, L, C, D, Q) and DC bias capability, which means the choice between them is driven primarily by the required frequency range, the need for gain-phase transmission measurement, and the measurement accuracy required at the application's test frequency.

Each model below is its own dedicated product page with condition-matched pricing. Pre-Owned units are graded against the datasheet's published specifications during inspection, and each pre-owned configuration is priced according to the specific condition and accessory state of that unit. Click through to each model's page to see current availability and the condition options offered.

The HP 4194A's combination of impedance and gain-phase measurement in one instrument makes it the right choice when a single bench setup must characterize both component impedance and two-port network transmission behavior. With the optional HP 41941A or HP 41941B Impedance Probe Kit installed, the same instrument extends its impedance coverage to 100 MHz, addressing applications above the 40 MHz limit of the base configuration.

The clearest dividing line between these two analyzers is frequency coverage and measurement scope. The HP 4192A operates from 5 Hz to 13 MHz with 0.15% basic accuracy on impedance and a measurement range from 1.0000 Ω to 1.000 MΩ — well suited to low-frequency component, materials, and electrochemical impedance work. The HP 4194A operates from 100 Hz to 40 MHz on impedance (0.17% basic accuracy, 10 mΩ to 100 MΩ range) and adds 10 Hz to 100 MHz gain-phase measurement that the HP 4192A does not offer.

DC bias range is also different between the two instruments: the HP 4194A supports up to ±40 V DC bias, while the HP 4192A supports up to ±35 V. OSC level ranges and accuracy are application-specific and are documented in the specifications table that follows. For applications that require impedance measurement above 40 MHz, the HP 4194A paired with the HP 41941A or HP 41941B Impedance Probe Kit reaches 100 MHz at a 100 mΩ to 1 MΩ measurement range.

Additional differences in specifications beyond the few shown above are not listed here — see each model's full specifications below.

Product Core & Specifications

About this used unit

• Warranty included on every unit
• Functional verification included against datasheet specifications
• Standard Calibration Upgrade Options: No Calibration Required, NIST Traceable, Z540.1 or ISO 17025 with Data, Z540.3 Guardbanding with Data.
• Note that unnecessary accessories may not be included (contact Test Architect to confirm).

Please review the Manufacturer's Data Sheet to verify published specifications. Feedback on this webpage is always welcome — please reach out to your Test Architect at any time for questions or concerns. Thank you, we truly appreciate you being our customer.