Agilent/Keysight 1157A

The Agilent/Keysight 1157A is a 2.5 GHz active probe engineered to acquire high-frequency signals with minimal loading on the Device Under Test. Its high input impedance and low capacitance deliver accurate measurements across analog and digital waveforms while preserving signal integrity in demanding test environments.

Technical Specifications

• Bandwidth: 2.5 GHz


• Input Impedance: 100 kΩ, 0.8 pF (non-resonant)


• Rise Time: 140 ps (110 Ω resistive signal pin with solderable ground socket)


• Dynamic Range: 5 V peak-to-peak; >12 V peak-to-peak for edges exceeding 3 ns


• Voltage Offset: ±15 V

Key Features

• AutoProbe interface enables automatic oscilloscope configuration on compatible instruments


• Multiple probe tip configurations optimize performance across different measurement scenarios


• 110 Ω resistive signal pin (green) with solderable ground socket achieves full 2.5 GHz bandwidth and 140 ps rise time


• 130 Ω resistive signal pin (orange) with ground blade assembly option


• Resistive signal leads in 5 cm and 10 cm lengths support surface-mount and through-hole applications


• Micro clip attachment for precision probing of compact nodes


• Dedicated ground socket (E2637A) available separately


• Compact form factor facilitates access to densely populated circuit areas

Typical Applications The 1157A addresses high-speed analog and digital signal measurement where probe loading must be minimized. Its low input capacitance and non-resonant design suppress overshoot and ringing artifacts common in high-impedance circuits. Applications include design validation, signal integrity analysis, and troubleshooting on circuits operating in the multi-gigahertz range.

Compatibility & Integration The probe integrates with Keysight Infiniium Series and InfiniiVision 5000, 6000, and 7000 Series oscilloscopes (excluding 6000 Series 100 MHz models). AutoProbe compatibility eliminates manual probe configuration, reducing setup time and ensuring consistent measurement parameters across test sessions.