Agilent 33120A - Arbitrary Waveform Generator

Agilent 33120A — Arbitrary Waveform Generator

15 MHz • 40 MSa/s • 12‑bit Arbitrary Waveforms • AM/FM/FSK • Sweep • Burst

Purpose & Capabilities

A professional‑grade arbitrary waveform/function generator designed for:

• Analog and digital circuit testing

• Filter and amplifier characterization

• Sensor simulation

• Audio and low‑RF experiments

• Microcontroller and logic stimulation

• Educational and lab‑grade signal generation

The Agilent 33120A is known for exceptionally clean output, stable DDS performance, and high‑quality arbitrary waveform capability.

Access Level

• General Member Use

• No reservation required

• Only authorized volunteers may service or calibrate the unit

• Use caution when connecting to sensitive circuits

Specifications

Waveform Generation

• Waveforms:

  • Sine

  • Square

  • Triangle

  • Ramp

  • Pulse

  • Noise

  • Arbitrary waveforms

• Max Frequency:

  • 15 MHz
    (sine)

  • Lower limits for square/pulse depending on duty cycle

• Sampling Rate:
  40 MSa/s

• Vertical Resolution:
  12‑bit

• Arb Memory:
  16,000 points

• DDS Architecture:
  Yes

Output Characteristics

• Output Impedance:
  50 Ω

• Amplitude:
  Up to 10 Vpp into 50 Ω (20 Vpp open‑circuit)

• DC Offset:
  Adjustable

• Rise/Fall Times:
  Fast DDS edges

• Modulation:

  • AM

  • FM

  • FSK

  • PWM

  • Sweep (linear/log)

  • Burst

Additional Features

• Built‑in 100 kHz frequency counter

• GPIB + RS‑232
  (for remote control)

• Nonvolatile memory for saved setups

• Front‑panel numeric keypad + soft keys

Before You Begin

• Inspect the unit:

  • Ensure BNC connectors are clean

  • Verify output amplitude is set low before connecting

  • Check that the output is OFF before wiring

• Use proper cables:

  • 50 Ω coax recommended

  • Avoid long unshielded leads

• Confirm your circuit can handle the selected amplitude and offset

Operating Guidelines

Basic Setup

• Select waveform type

• Set frequency, amplitude, and offset

• Choose output impedance (50 Ω recommended)

• Enable output only after settings are correct

Arbitrary Waveforms

• Use built‑in shapes or upload via GPIB/RS‑232

• Useful for:

  • Custom modulation

  • Simulating sensors

  • Non‑sinusoidal test signals

  • Digital noise patterns

Modulation Modes

• AM/FM:
  For analog experiments

• FSK:
  For digital communication simulation

• PWM:
  For microcontroller‑like signals

• Sweep:
  For filter characterization

• Burst:
  For gated or one‑shot signals

Frequency Counter

• Connect signal via dedicated input

• Ensure amplitude is within safe range

• Useful for verifying oscillators or clock signals

Supported Use Cases

Approved:

• Audio experiments

• Filter testing

• Logic circuit stimulation

• Oscillator verification

• Analog prototyping

• Sensor simulation

• Educational labs

Not approved:

• Driving motors

• High‑current loads

• High‑voltage circuits

• RF beyond 15 MHz

• Direct connection to inductive loads without protection

Care & Etiquette

• Do not yank BNC cables

• Turn output OFF before changing connections

• Keep amplitude reasonable — avoid slamming circuits with high voltage

• Return cables neatly

• Report:

  • Distorted output

  • Frozen display

  • Noisy or unstable waveforms

  • Keypad or encoder issues

Common Issues & Troubleshooting

• Distorted waveform

  • Load not 50 Ω

  • Amplitude too high

• No output

  • Output disabled

  • Wrong waveform selected

• Frequency counter unstable

  • Signal too weak or noisy

• Arb waveform errors

  • Memory full or invalid format