This manual provides operating instructions, safety guidelines, specifications, and programming details for the Stanford Research Systems SR844 RF Lock-In…
The document serves as a comprehensive user guide for the SR844 RF Lock-In Amplifier manufactured by Stanford Research Systems. It covers essential topics including safety precautions regarding high voltages and photomultipliers, initial setup procedures involving line voltage selection, and an overview of the instrument's functional blocks such as the signal input path and digital signal processor.
The guide details operational procedures for configuring time constants, sensitivity, and reference channels, alongside explanations of display outputs like X, Y, R, θ, and dBm. It also includes sections on using the device as a double lock-in, performing noise measurements, and utilizing auxiliary inputs and outputs for advanced signal processing applications.
| Bandwidth | 25 kHz to 200 MHz |
|---|---|
| Input Impedance | 50 Ω or 1 MΩ || 30 pF |
| Full Scale Sensitivity | 100 nV to 1V rms |
| Gain Accuracy (< 50 MHz) | ±0.25 dB |
| Power Consumption | 70 Watts |
| Operating Temperature | +10 °C to +40 °C |
A 1/2 Amp fuse is required for 220V/240V operation.
Specifications apply after 30 minutes of warm-up.
The typical input noise is less than 8 nV/√Hz.