The model 197 is a compact, high performance chopper, offering features and benefits that are ideal for use in modern photometic systems.
- Without external controller
- Double opening
- Internal and external opening
- Synchronization outputs
The unit is self contained, comprising a dual aperture chopper blade, motor and the necessary driving electronics. Each aperture provides an independent reference output allowing simultaneous dual frequency operation (10:1 ratio) for dual-path experiments. Frequency control is by a precision internal oscillator set by a 4-digit push-button selector on the unit or by the application of an external AC reference signal. The unit is powered via an external line power supply module.
- Modulation 1: 150Hz to 3000Hz
- Modulation 2: 15Hz to 300Hz
- Accuracy ± 20 ppm at 25 ºC
- Manual or external control (0.5V to 10V sinuzoidal or peak to peak)
- 10V peak-to-peak sync paths
- Absorption, reflection and optical transmission
- Dual radiometric measurement