The Advantest R3261C is a spectrum analyzer for RF and microwave measurements across 9 kHz to 2.6 GHz. It delivers a 120 dB display dynamic range with amplitude measurement capability from -130 dBm to +25 dBm and 1 dB typical level accuracy. A synthesized local oscillator provides ±2 × 10⁻⁸/day frequency stability with 1 Hz resolution tuning. The instrument incorporates a tracking generator for frequency characteristic measurements, multi-marker analysis with counter mode capability, and manual sweep functionality for spot measurements.
Technical Specifications
Frequency Coverage: 9 kHz to 2.6 GHz with 1 Hz resolution synthesizer and counter.
Resolution Bandwidth: Switchable 30 Hz to 1 MHz in 1 to 3 dB steps; 6 dB bandwidths at 200 Hz, 9 kHz, and 120 kHz. Bandwidth accuracy ≤20%.
Amplitude Range: -130 dBm to +25 dBm with ±50 VDC maximum DC input. Maximum input +25 dBm at ≥30 dB attenuation.
Noise Performance: Average noise -121 dBm + 1.55f(GHz) dB; sideband noise ≤-105 dBc/Hz at 20 kHz offset (f ≤3.0 GHz); single-sideband noise floor -120 dBc/Hz minimum.
Selectivity: ≤15:1 (60 dB:3 dB).
Frequency Stability: ±2 × 10⁻⁷/year (internal reference); ±5 × 10⁻⁸ temperature stability (0–50°C); residual FM ≤50 kHz p-p at span ≤2 MHz; frequency drift ≤300 Hz/min after 1 hour warm-up.
Sweep: 50 ms to 1000 s programmable; manual sweep available.
Input: 50 Ω impedance, N-type connector.
Power: 90–132 V or 198–250 V, 48–66 Hz.
– Key Features
• Multi-marker system with active marker and pause functions for signal identification
• 1 Hz resolution frequency counter and start/stop frequency control
• Tracking generator for filter and amplifier characterization
• User-defined function menu customization
• Measuring window function for localized spectral analysis
• IC memory card for data and panel setting storage/recall
• Full GPIB remote control with optional controller function
• Serial I/O interface support
– Typical Applications
• RF component and subsystem testing
• Microwave signal analysis and troubleshooting
• Frequency response measurements via tracking generator
• Noise figure and phase noise characterization
– Compatibility & Integration
GPIB, serial I/O, and optional controller function enable integration into automated test systems and production environments.


















