The Agilent/Keysight 8656B is a programmable synthesized signal generator delivering stable, low-distortion RF signals from 0.1 MHz to 990 MHz. Built for manufacturing test, R&D, and field service environments, it combines precise frequency control with flexible modulation and remote programmability via HP-IB interface.
Technical Specifications
Frequency & Timing
• Frequency range: 0.1 to 990 MHz (underrange capability to 10 kHz)
• Frequency resolution: 10 Hz
• Frequency switching speed: <35 ms
• Internal reference aging: 2 ppm/year
• High stability timebase (Option 001): 1.5 × 10⁻⁸/day
Output Power
• Level range: +13 dBm to −127 dBm
• Level accuracy: ±1.0 dB
• Level resolution: 0.1 dB
• SWR: −5 dBm); <1.5 (levels <−5 dBm)
• Reverse power protection: 25 W
Modulation
• AM and FM modulation supported
• Internal modulation rates: 400 Hz, 1 kHz
• External modulation bandwidth: DC to 50 kHz (DC coupled); 20 Hz to 50 kHz (AC coupled)
• FM distortion: <1.5% (all specified deviations, DC to 100 kHz); typically 1 kHz); <0.5% (internal rates, ≥3 kHz peak deviation)
• Incidental AM: <0.1% (center frequency ≥500 kHz, peak deviation <20 kHz, internal rates)
• Simultaneous and mixed modulation modes from internal and external sources
Signal Quality
• SSB phase noise: −126 to −114 dBc
– Key Features
• 100 non-volatile save/recall registers for front panel settings
• Full HP-IB remote programming with standard functions (SHO, AH1, TO, L2, SRO, RL1, PP0, DC1, DTO, CO, E1)
• Selectable AC power: 100/120/220/240 VAC (±5%, −10%), 48–440 Hz; 125 VA max
• Operating temperature: 0 to +55°C
• RF leakage: <1.0 µV (two-turn 2.5 cm loop at 2.5 cm from front surface)
– Physical
• Dimensions: 133H × 425W × 520D mm
• Net weight: 18.1 kg
