Noise spectrum analyzer software

The detector noise characterization system is controlled using an in-house software package developed with Microsoft Visual Basic. The system is based on an SR785, dual channel, Fourier transform, dynamic signal analyzer and SR550, low noise preamplifier. The software uses the GPIB interface to communicate with the instrument. The software capabilities include: control all the front panel functions (except power on) through the software, read data from the SR785, record data in an embedded Microsoft Excel workbook, with single channel or dual channel modes.

Instrument configuration of the noise measurement setup

Block diagram of the noise measurement setup. The sample, a power supply (battery), a bias resistor, and a low noise preamplifier are placed inside the noise-shielding cage. The sample is mounted in the same dewar system which is used for spectral measurements. A thick copper plate at the sample temperature is used as the radiation block to provide dark conditions for the detector.

The main user interface for the noise spectrum analyzer software showing real experimental data taken from the samples.

Spectrum analyzer control panel. On screen buttons allow the user to change the parameters remotely without using the instrument front panel buttons.