The Keysight (formerly Agilent / HP) 8644A is a high-performance synthesized RF signal generator covering 251.5 kHz to 1030 MHz, designed for demanding R&D and manufacturing tests of communications systems. Known for its exceptional spectral purity, low phase noise, and highly accurate modulation capabilities, the 8644A utilizes a modular architecture to support diverse configurations, including options for high-stability oven timebases, enhanced low phase noise, and high-performance pulse modulation.

Specifications

Frequency

ParameterValue
Maximum Frequency1.03 GHz

Output

ParameterValue
Maximum Output Power+16 dBm
Output Power Range-137 dBm to +16 dBm

General

ParameterValue
InterfacesGPIB (IEEE-488)

Frequency Specifications

ParameterValue
Internal Reference Frequency10 MHz

Amplitude / Output Level

ParameterValue
Output Impedance50 ohms

Spectral Purity

ParameterValue
SSB Phase Noise with Option 004 (1 GHz Carrier, 20 kHz Offset)< -136 dBc/Hz
SSB Phase Noise (515 MHz Carrier, 20 kHz Offset)< -137 dBc/Hz

Internal Modulation Source

ParameterValue
Internal Audio Frequency Range0.1 Hz to 400 kHz
Internal Audio Frequency Resolution0.1 Hz

Input & Output Ports

ParameterValue
RF Output Connector TypeType-N female
External Modulation Input ConnectorsBNC female (front panel)
Internal Modulation/LF Output ConnectorBNC female (front panel)
10 MHz Reference Input ConnectorBNC female (rear panel)
10 MHz Reference Output ConnectorBNC female (rear panel)

Physical Characteristics

ParameterValue
Rack Unit Height4U

Ordering Options & Accessories

ParameterValue
Option 001High-Stability Oven Timebase
Option 004Rear Panel RF Output and Modulation Inputs
Option 005Electronic Attenuator

Options

ParameterValue
Option 010Reduced RF Leakage
Option 907Front Handle Kit
Option 908Rack Flange Kit
Option 909Rack Flange Kit with Front Handles
Option 910Extra Operating and Service Manual Set

Environmental

ParameterValue
Maximum Operating Altitude4,600 m (15,000 ft)
Maximum Storage Altitude15,200 m (50,000 ft)

Power Requirements

ParameterValue
AC Input Voltage90 to 132 Vac / 198 to 264 Vac (manually selectable)
AC Input Frequency Range48 to 440 Hz (for 90 to 132 Vac) / 48 to 66 Hz (for 198 to 264 Vac)

RF Emissions

ParameterValue
Standard RF Leakage< 1.0 µV induced in a 1-inch, 2-turn loop 1 inch from any surface

Reference Oscillator

ParameterValue
Option 001 Reference Aging Rate (Per Day)< 5 × 10^-10
Standard Reference Aging Rate (Per Year)< 2 × 10^-6

Interfaces

ParameterValue
Default GPIB Address19

Technology

Synthesized Signal Generator

Applications

RF Communications Testing, Receiver Sensitivity testing, Spectral Purity measurements, R&D