HP / Agilent 3325B Synthesizer/Function Generator

The HP/Agilent 3325B is a dual-mode signal source combining synthesizer precision with function generator flexibility. It delivers microhertz-resolution frequency control from 1 µHz to 20.999 MHz (sine) and 10.999 MHz (square, triangle, ramp), making it ideal for precision testing, calibration, and automated measurement systems. The instrument generates seven waveform types with exceptional phase control (±719.9°, 0.1° resolution) and supports phase-continuous sweeps across 100 programmable segments. Harmonic distortion remains better than -65 dBc up to 50 kHz, with spurious levels reaching -70 dBc. Multi-unit phase-locking enables coherent multi-channel applications.

## Technical Specifications

**Frequency & Resolution**
• Sine wave: 1 µHz to 20.999 MHz
• Square, triangle, ramps: 1 µHz to 10.999 MHz
• Sync output: DC to 60 MHz (TTL)
• Frequency resolution: Microhertz (µHz)
• Phase control: ±719.9° with 0.1° resolution

**Waveforms & Signal Quality**
• Sine, square, triangle, positive/negative ramps, arbitrary (ARB), DC offset
• Harmonic distortion (sine): <-65 dBc (≤50 kHz); -60 dBc (200 kHz); -40 dBc (2 MHz); -30 dBc (15 MHz); -25 dBc (20 MHz)
• Spurious levels: ≤-70 dBc
• Square rise/fall time: ≤20 ns; overshoot <5%; settling <1 µs
• Triangle linearity: 0.05% (≤10.999 kHz)

**Amplitude & Output**
• DC offset: ±5V (typical)
• Amplitude accuracy: ±200 mV (typical)
• Output impedance: <2 Ω (DC), <10 Ω (1 MHz)
• Isolated floating outputs

**Modulation & Sweep**
• Internal modulation sources: sine, square, arbitrary waveforms
• Sweep modes: LOG, LIN, discrete (100-segment capability)
• Phase-continuous sweep supported

## Key Features

• Microhertz resolution across 20 MHz span
• 10 non-volatile memory locations for test setup storage
• Programmable modulation with internal waveform sources
• Exceptional phase continuity for multi-unit synchronization
• Self-test capability (front panel or remote)

## Typical Applications

Precision frequency calibration, phase-coherent multi-channel testing, harmonic analysis, modulation characterization, automated test system integration, and communication system validation.

## Compatibility & Integration

HP-IB (IEEE-488) and RS-232 interfaces enable remote control and integration into automated test environments. Optional high-stability frequency reference (Option 001) provides ±5×10⁻⁷/week aging and ±1×10⁻⁷/month long-term stability.