The Keysight (formerly Agilent HP) 8657A is a robust, synthesized RF signal generator designed for versatile receiver testing. Covering a frequency range from 100 kHz to 1040 MHz, it offers simultaneous and mixed AM and FM modulations, a high-quality solid-state electronic attenuator for enhanced reliability, and excellent spectral purity, making it ideal for both in-channel and out-of-channel test applications.

Specifications

Frequency

ParameterValue
Minimum Frequency100 kHz
Maximum Frequency1040 MHz

Output

ParameterValue
Maximum Output Power+13 dBm
Output Power Range+13 to -143.5 dBm
Phase Noise<-130 dBc/Hz at 20 kHz offset (500 MHz carrier)

General

ParameterValue
InterfacesGPIB (IEEE-488)

Frequency Specifications

ParameterValue
Frequency Switching Speed< 35 ms
Option 001 Reference Aging Rate< 5 x 10^-10 per day
External Reference Input Frequency1, 2, 5, or 10 MHz

Amplitude and Output

ParameterValue
Minimum Output Level-143.5 dBm
Level Accuracy±1.0 dB (levels > -127 dBm, typically ±0.5 dB)
Output Impedance50 ohms
Reverse Power Protection (RF)50 Watts (from a 50 ohm source)
Reverse Power Protection (DC)50 VDC
Attenuator TypeAll-electronic solid-state attenuator

Spectral Purity

ParameterValue
Harmonics<-30 dBc (for levels < +7 dBm)

Amplitude Modulation (AM)

ParameterValue
AM Depth Range0 to 99%
AM Resolution1%

Frequency Modulation (FM)

ParameterValue
FM Modulation Frequency Response (3 dB)DC to 100 kHz (DC-coupled) or 50 Hz to 100 kHz (AC-coupled)

Internal Modulation Source

ParameterValue
Internal Modulation Frequencies400 Hz and 1000 Hz

Physical and Environmental

ParameterValue
Operating Temperature Range0 to 55 °C

RF Output

ParameterValue
Level Resolution0.1 dB
RF Output ConnectorType-N female (front panel standard, rear panel with Option 002)

System Features

ParameterValue
Storage Registers100 non-volatile registers (00 to 99)

Options

ParameterValue
Option 002 Rear Panel ConfigurationMoves RF output and modulation input/output connectors to the rear panel

Technology

Synthesized RF Signal Generator

Applications

Receiver testing, RF component characterization, general laboratory use