The Keysight (Agilent) E8251A is a high-performance analog RF/microwave signal generator belonging to the PSG-A series. Operating over a broad frequency range of 250 kHz to 20 GHz with ultra-fine 0.01 Hz resolution, it provides outstanding level accuracy, dual internal modulation generators, and high output power options, making it a benchmark tool for testing high-power devices and accurate device characterization.

Specifications

Frequency

ParameterValue
Minimum Frequency250 kHz
Maximum Frequency20 GHz
Frequency Resolution0.01 Hz
Frequency Range250 kHz to 20 GHz
Frequency Extension LimitUp to 110 GHz with Agilent 83550 Series millimeter-wave source modules
Frequency Switching Speed< 15 ms (typical)

Output

ParameterValue
Maximum Output Power+13 dBm (+20 dBm with Option 1EA)
Output Power Range+13 dBm standard, +20 dBm with Option 1EA at 20 GHz
Phase Noise-110 dBc/Hz @ 20 kHz offset, 10 GHz carrier

Modulation

ParameterValue
ModulationAM, FM, Phase (ΦM), Pulse
Sweep ModesDigital Sweep (List and Step)

General

ParameterValue
InterfacesGPIB (IEEE-488.2), 10Base-T LAN, RS-232
DisplayColor LCD
Standard Warranty1-Year standard (5-Year optional)

Physical

ParameterValue
Power Supply90 to 264 VAC, 47 to 440 Hz, 250 W maximum
Dimensions (W×H×D)178 mm H x 426 mm W x 515 mm D
Weight< 21 kg

Amplitude

ParameterValue
Level Accuracy±0.7 dB to ±0.9 dB
Maximum Output Power (Standard)+13 dBm at 20 GHz
Maximum Output Power (Option 1EA)+20 dBm at 20 GHz

Spectral Purity

ParameterValue
Standard Phase Noise (10 GHz Carrier, 1 kHz offset)-85 dBc/Hz
Standard Phase Noise (10 GHz Carrier, 20 kHz offset)-110 dBc/Hz
Option UNJ Phase Noise (10 GHz Carrier, 1 kHz offset)-98 dBc/Hz
Option UNJ Phase Noise (10 GHz Carrier, 10 kHz offset)-110 dBc/Hz
Harmonics<-30 dBc (for carrier frequencies < 20 GHz at standard power, typical)
Spurious (Non-Harmonics)< -60 dBc (for carrier frequencies > 10 to 20 GHz)

Analog Modulation

ParameterValue
Internal Modulation WaveformsSine, square, triangle, positive/negative ramp, Gaussian Noise, Uniform Noise, Swept Sine, Dual Sine
Internal Modulation Rate RangeUp to 1 MHz
Modulation Signal SourceDual internal generators

Sweep and Operating Modes

ParameterValue
Sweep Mode CapabilitiesList and Step digital sweeps with user flatness correction at the test port

Output Power

ParameterValue
Step Attenuator0 to 115 dB in 5 dB steps (Option 1E1)

Environmental

ParameterValue
Operating Temperature Range0 to 55 °C
Storage Temperature Range-40 to 71 °C

Pulse Modulation

ParameterValue
Pulse Modulation Rise/Fall Time< 10 ns (6 ns typical)
Pulse Modulation On/Off Ratio> 80 dB

Amplitude Modulation (AM)

ParameterValue
AM Rate (3 dB Bandwidth)DC to 100 kHz
Maximum AM Depth90%

Frequency Modulation (FM)

ParameterValue
FM Maximum Deviation10 MHz (at 20 GHz)

Power Requirements

ParameterValue
Power Consumption< 250 W
AC Voltage Compatibility90 to 267 V AC
AC Frequency Compatibility45 to 440 Hz

Frequency Reference

ParameterValue
Internal Reference Aging Rate< ±1 x 10^-8/day (standard); < ±5 x 10^-10/day (Option UNJ)
External Reference Input1, 2, 5, 10 MHz (within ±1 ppm)

Inputs & Outputs

ParameterValue
RF Output ConnectorPrecision 3.5 mm male

Technology

Analog RF/Microwave

Applications

RF & Microwave Testing, Device Characterization, Radar & Receiver Testing