The HP 3326A is a high-performance two-channel synthesized function generator from Keysight Technologies (formerly Agilent / Hewlett-Packard). It integrates two independent synthesizers into a single instrument under microprocessor control, enabling versatile multi-channel signal generation, coordinated sweeps, and precise phase offset control.

Specifications

General

ParameterValue
InterfacesHP-IB (GPIB)
DisplayLED

Physical

ParameterValue
Power Supply100 / 120 / 220 / 240 V AC (selectable), 48 - 66 Hz
Operating Temperature0 to 55 °C
Dimensions (W×H×D)425.5 mm × 132.6 mm × 497.8 mm
Weight19 kg

Frequency Characteristics

ParameterValue
Frequency Range (Sine)1 µHz to 13 MHz
Frequency Range (Square)1 µHz to 1 MHz
Frequency Resolution (below 100 kHz)1 µHz
Frequency Resolution (at or above 100 kHz)1 mHz
Available WaveformsSine, Square, and DC

Amplitude and DC Offset

ParameterValue
AC Amplitude Range1 mV to 10 Vp-p
DC Offset Range±4.5 mV to ±4.5 V (dependent on selected AC amplitude)
Output Impedance50 Ω
DC Offset AvailabilityCan be added to either output in any mode

Dual-Channel and Phase Control

ParameterValue
Operating ModesTwo-Channel, Two-Tone, Two-Phase, Pulse
Two-Channel ModeChannels A and B operate independently
Two-Tone ModeChannel B frequency must be within 100 kHz of Channel A
Two-Phase ModeChannels A and B operate at the exact same frequency with a calibrated phase difference
Pulse ModeChannel B is the complement of the Channel A output
Channel-to-Channel Phase Offset Range±720°
Phase Resolution0.01°

Modulation and Sweep Capabilities

ParameterValue
Modulation TypesAmplitude Modulation (AM), Phase Modulation (PM)
Internal Amplitude ModulationAvailable on Channel A in Two-Channel mode (Channel B as sine/square source)
External Amplitude ModulationAvailable on all modes, independent for each channel
Internal Phase ModulationAvailable on Channel A in Two-Channel mode (Channel B as source)
External Phase Modulation (Two-Channel)Available on either or both channels
External Phase Modulation (Other Modes)Applied to both channels simultaneously
Synchronous Phase ModulationAvailable on both channels in Two-Tone, Two-Phase, and Pulse modes
Sweep TypesLinear (Linear Ramp, Triangular) and Discrete
Sweep Phase ContinuityPhase continuous frequency sweep
Linear Sweep DirectionsFrequency can increase or decrease (up-down continuous in Triangular mode)
Discrete Sweep Sequence CapacityUp to 63 frequency pairs
Discrete Sweep Switching Time (<1 MHz change)Typically 10 ms
Coordinated SweepingMicroprocessor-controlled coordinated sweeping of both outputs

Options

ParameterValue
Option 002 High Voltage Frequency RangeDC to 1 MHz
Option 002 High Voltage Amplitude Range4 mV to 40 Vp-p
High Stability Timebase OptionOption 001
High Voltage Output OptionOption 002

Timebase and Reference Oscillator

ParameterValue
External Reference Input1, 2, 5, or 10 MHz
Reference Output10 MHz

System Interfaces and Control

ParameterValue
Instrument CalibrationMicroprocessor-controlled internal self-calibration
Microprocessor ControlSimultaneous control of both synthesizers with simplified operation

Performance

ParameterValue
Harmonic Distortion (Sine)≤ -80 dBc (0.1 Hz to 100 Hz), ≤ -70 dBc (100 Hz to 100 kHz), ≤ -50 dBc (100 kHz to 1 MHz), ≤ -40 dBc (1 MHz to 13 MHz)
Spurious Signals (Non-Harmonic)≤ -80 dBc
Phase Noise≤ -115 dBc/Hz at 10 kHz offset from carrier
Amplitude Flatness (Sine)±0.1 dB (100 Hz to 100 kHz, relative to 10 kHz)

Standard Timebase

ParameterValue
Reference Output Frequency10 MHz
Reference Output Level≥ 0 dBm into 50 Ω
Aging Rate±5 × 10^-6 per year

High Stability Timebase (Option 001)

ParameterValue
Option 001 Aging Rate±5 × 10^-10 per day (after 72 hours warm-up)
Option 001 Temperature Stability±1 × 10^-8 (0 °C to 55 °C)

Rear Panel Connections

ParameterValue
External Modulation InputsBNC, AM and PM inputs for Channel A and Channel B
Sweep Control OutputsBNC, X-Drive (0 to 10 V sweep voltage ramp) and Z-Blank (TTL)
External Sweep Trigger InputBNC, TTL-compatible

Sweep

ParameterValue
Sweep Time Range (Linear)20 ms to 1000 s
Sweep Time Range (Log)1 s to 1000 s

Inputs & Outputs

ParameterValue
Sweep X-Drive Output0 to +10 V ramp
Rear Panel Sync OutputsTTL compatible into ≥ 50 Ω, 0.1 Hz to 13 MHz
Z-Axis Blanking OutputTTL level
Marker OutputTTL level

Modulation

ParameterValue
AM Modulation Depth Range0% to 100%

Reference & Timebase

ParameterValue
Standard Timebase Temperature Stability±5 × 10^-6 (0 °C to 55 °C)

Power Requirements

ParameterValue
Power Consumption150 VA maximum
Line Voltage Selection100 V / 120 V / 220 V / 240 V (selectable, +5% to -10%)
Line Frequency Range48 Hz to 66 Hz

Environmental

ParameterValue
Operating Humidity< 95% relative humidity (0 °C to 40 °C)
Storage Temperature-40 °C to +75 °C

Interfaces

ParameterValue
GPIB Interface FunctionsSH1, AH1, T6, L4, SR1, RL1, PP0, DC1, DT1, C0, E1

Technology

Synthesized Function Generator

Applications

Coordinated multi-channel signal generation, two-tone testing, and phase-locked signal simulation