The Keysight (formerly Agilent / HP) 8643A is a high-performance synthesized signal generator designed for demanding out-of-channel receiver testing and general-purpose RF applications. Offering superb spectral purity with non-harmonic spurious levels below -100 dBc up to 1 GHz and an SSB phase noise of -130 dBc/Hz at 20 kHz offset, the 8643A delivers exceptional accuracy and reliability. Its electronic attenuator on the 1 GHz version replaces mechanical relays with solid-state components to achieve excellent output level accuracy of +/-1.0 dB down to -127 dBm. Standard features include pulse modulation, a 0.1 Hz to 400 kHz internal modulation synthesizer with two-tone capability, and support for sine, square, triangle, sawtooth, and white Gaussian noise waveforms.
Specifications
Frequency
| Parameter | Value |
|---|---|
| Minimum Frequency | 252 kHz |
| Maximum Frequency | 1030 MHz (expandable to 2.06 GHz with Option 002) |
| Frequency Resolution | 0.01 Hz |
Output
| Parameter | Value |
|---|---|
| Maximum Output Power | +13 dBm |
| Output Power Range | -137 dBm to +13 dBm |
| Phase Noise | <-130 dBc/Hz (at 20 kHz offset, 1 GHz carrier) |
Modulation
| Parameter | Value |
|---|---|
| Modulation | AM, FM, Phase Modulation, Pulse Modulation |
General
| Parameter | Value |
|---|---|
| Interfaces | GPIB (IEEE-488.2) |
| Display | Liquid Crystal Display (LCD) |
Frequency Specifications
| Parameter | Value |
|---|---|
| Frequency Range | 252 kHz to 1030 MHz (expandable to 2060 MHz with Option 002) |
| Internal Reference Frequency | 10 MHz |
| External Reference Input Frequency | 1, 2, 5, 10 MHz |
Amplitude & Output Power
| Parameter | Value |
|---|---|
| Absolute Level Accuracy | +/-1.0 dB (down to -127 dBm) |
| Minimum Output Level | -137 dBm |
| Output Impedance | 50 ohms |
| Reverse Power Protection (RF) | 50 Watts (from 50 ohm source) |
| Attenuator Type | Electronic (solid-state, up to 1 GHz) |
Spectral Purity
| Parameter | Value |
|---|---|
| Non-Harmonic Spurious | <-100 dBc (up to 1 GHz, at offsets >10 kHz) |
| Harmonics | <-30 dBc (for output levels < +10 dBm) |
| SSB Phase Noise (1 kHz offset) | <-110 dBc/Hz (at 1 GHz carrier) |
| Residual FM | < 1.5 Hz RMS (in 300 Hz to 3 kHz BW, at 1 GHz carrier) |
| Broadband Noise Floor | < -140 dBc/Hz (at > 20 MHz offset, < 1030 MHz carrier) |
Frequency Modulation (FM)
| Parameter | Value |
|---|---|
| Maximum FM Deviation | Up to 10 MHz (carrier frequency dependent) |
| FM Frequency Response | DC to 100 kHz (DC-coupled), 20 Hz to 100 kHz (AC-coupled) |
Amplitude Modulation (AM)
| Parameter | Value |
|---|---|
| Maximum AM Depth | 100% |
| AM Resolution | 0.1% |
Internal Modulation Source
| Parameter | Value |
|---|---|
| Internal Modulation Synthesizer Range | 0.1 Hz to 400 kHz |
| Internal Waveforms Available | Sine, square, triangle, sawtooth, white Gaussian noise |
Interfaces & Connectivity
| Parameter | Value |
|---|---|
| RF Output Connector Type | Type-N female (front panel) |
Physical & Environmental
| Parameter | Value |
|---|---|
| Operating Temperature Range | 0 to 55 °C |
| Storage Temperature Range | -40 to 71 °C |
Options & Accessories
| Parameter | Value |
|---|---|
| Option 001 | High Stability Timebase |
| Option 002 | 2.06 GHz Frequency Extension |
Reference Oscillator
| Parameter | Value |
|---|---|
| Reference Output Frequency | 10 MHz |
| External Reference Input Frequencies | 1, 2, 5, 10 MHz (±10 ppm) |
RF Output
| Parameter | Value |
|---|---|
| Level Resolution | 0.1 dB |
Power Requirements
| Parameter | Value |
|---|---|
| AC Input Voltage | 90 to 132 Vac or 198 to 264 Vac (automatically selected) |
| AC Input Frequency | 47 to 440 Hz |
Performance
| Parameter | Value |
|---|---|
| SSB Phase Noise (20 kHz offset) | <-130 dBc/Hz @ 1 GHz carrier |
Technology
Synthesized RF Signal Generator
Applications
Receiver out-of-channel testing, RF component characterization, general-purpose RF signal generation