Wavetek 148A

The Wavetek 148A is a dual-generator AM/FM/PM signal source delivering precision modulated waveforms across 0.0002 Hz to 20 MHz. The instrument combines a main function generator with an independent modulation generator, enabling complex waveform creation and precise timing control. The main generator produces sine, triangle, square, ramp, pulse, and DC outputs up to 30 V p-p with adjustable symmetry (1:19 to 19:1), amplitude, and DC offset. Sine distortion remains below 0.5% from 1 Hz to 10 kHz, while square wave symmetry holds within 1% across the same range. Pulse outputs deliver 25 ns minimum width at up to 10 MHz repetition rates.

The modulation generator supports AM (0–100% depth with suppressed carrier operation), FM (up to 1000:1 frequency ratio), and PM (±50° carrier phase shift). Both generators accept manual front-panel control and external voltage control for frequency sweep and modulation depth adjustment. The 50 Ω output impedance includes an overload indicator for clipping detection.

– Technical Specifications

• Main Generator Frequency: 0.0002 Hz to 20 MHz
• Output Amplitude: Up to 30 V p-p
• Waveforms: Sine, triangle, square, ramp, pulse, DC voltage
• Sine Distortion: <0.5% (1 Hz–10 kHz)
• Square Symmetry: ±1% typical (1 Hz–10 kHz)
• Pulse Width: 25 ns minimum
• Repetition Rate: 10 MHz maximum
• Symmetry Range: 1:19 to 19:1 continuously adjustable
• Output Impedance: 50 Ω (terminated)
• AM Depth: 0–100%, suppressed carrier capable
• FM Deviation: Up to 1000:1 frequency ratio
• PM Deviation: ±50° carrier phase shift

– Key Features

• Dual-generator architecture for simultaneous modulation and independent signal generation
• Three operational modes: continuous, triggered (external or internal source), gated (external or internal source)
• Selectable start/stop points (−90° to +90°) for triggered and gated operation
• Electrical frequency control via external voltage
• Overload LED for output clipping indication

– Typical Applications

Modulated signal generation, component characterization, communication system testing, trigger and timing control, waveform shaping for precision measurement.

– Compatibility & Integration

Accepts external modulation and trigger sources; manual and electrical control interfaces.