Tektronix VX4750 Function Generator Module

The Tektronix VX4750 is a single-channel VXIbus-compatible function generator module engineered for high-performance automated test systems and research environments. It generates sine, square, triangle, ramp, pulse, DC, and arbitrary waveforms up to 25 MHz with 1 ppm frequency accuracy. The module delivers programmable amplitude control, multiple modulation schemes (FM, PM, AM, PSK, FSK, PWM), and flexible sweep capabilities across its entire frequency range.

– Technical Specifications

Waveform Generation
• Waveform types: Sine, Square, Triangle, Positive Ramp, Negative Ramp, Pulse, DC, Arbitrary
• Maximum output frequency: 25 MHz
• Frequency accuracy: 1 ppm
• Frequency sweep: Programmable across entire frequency range
• Output control: Continuous or gated for programmable cycle count

Amplitude & Output
• High impedance load: 0.0 to 11 Vp
• 50 Ohm load: 0.0 to 5.5 Vp
• Amplitude accuracy (0.001 Hz to 3 MHz, 50 Ohm): ±0.2 dB (±0.1 dB typical)
• Amplitude accuracy (3 MHz to 25 MHz, 50 Ohm): ±0.5 dB
• Amplitude flatness (0.001 Hz to 3 MHz, 50 Ohm): ±0.2 dB
• DC offset: Programmable

Modulation
• Types: FM, PM, AM, PSK, FSK, PWM (PWM applies to pulse waveform only)
• FM (external): 2 Hz to 5 MHz deviation range, 2 Hz resolution, 2 kHz bandwidth, ±1.414 V modulating signal
• AM (external): 2 kHz bandwidth, ±1.414 V modulating signal
• Modulation sources: Internal and external

Synchronization
• Internal reference: 10 MHz (1 ppm accuracy)
• Reference sources: VXI CLK10, external REF IN connector, internal 10 MHz
• Front panel REF OUT: Buffered 10 MHz reference or 33 MHz module clock (programmable)
• TTL outputs: SWEEP SYNC (end of sweep), MARKER FREQ (programmable), polarity selectable

Physical & Environmental
• Dimensions: VXI C size (262 mm × 353 mm × 30.5 mm)
• Weight: 2.38 kg (5.25 lb)
• Operating temperature: 0°C to +50°C
• Storage temperature: -40°C to +85°C

– Key Features

• Programmable frequency sweep over 25 MHz range with marker and sync outputs
• Dual-output amplitude capability for 50 Ohm and high-impedance loads
• Independent FM and AM modulation from external sources
• Module clock capability with flexible reference distribution
• VXI C-size form factor for mainframe integration

– Typical Applications

• Automated test equipment requiring multiple waveform generation
• Signal conditioning in RF and mixed-signal characterization
• Frequency sweep applications with phase-locked synchronization
• Modulation testing in communications systems

– Compatibility & Integration

The VX4750 fits any VXIbus-compliant mainframe. EMC compliance with EN 55011 Class A, EN 50081-1, EN 60555-2, and IEC 801 series standards (requires mainframe backplane shields per VXIbus Specification Rule B.7.45).