## Resolution, Scanning Speed and Demodulation Bandwidth

on 06.12.2011 at 09:40 by Andrin on Blog of Andrin Doll
This post is about the interplay between resolution, scanning speed and demodulation bandwidth. I demonstrate how the scanning process can be described in spatial, time and frequency domain, and show that this is a valuable toolbox to analyze your measurement setup as a whole.

## Dynamic Plotting of HF2 Lock-in Data with Python

on 03.11.2011 at 18:06 by Lara Juricic on Blog of Jürg Schwizer
The Matplotlib is a library for creating 2D plots of arrays in Python. The purpose of this blog entry is to depict a general approach to enable continuous updating of figure data during the Python script execution. The figure update functionality is useful for plotting measurement data that is recorded with the Zurich Instruments HF2LI Lock-in amplifier.

## Exploring the HF2LI-MOD: Measuring Bessel Functions

on 20.10.2011 at 12:40 by Andrin on Blog of Andrin Doll
In this post, I demonstrate the capabilities of the HF2LI-MOD upgrade by demodulating 4 FM sidebands simultaneously. With the help of a basic sweep routine programmed in LabVIEW, I measure 5 Bessel functions by direct sideband demodulation of an FM signal. This post might give you an inspiration on how to improve your measurement sensitivity by introducing an advanced demodulation scheme of multiple sidebands.

## Amplitude and Frequency/Phase Modulation Explained

on 20.10.2011 at 09:22 by Michele Zaffalon on Blog of Michele Zaffalon
I always had difficulties in understanding frequency modulation (FM) and its frequency spectrum. Even for the pure tone modulation, the FM spectrum consists of an infinite number of sidebands whose signs change from one sideband to the next one and whose amplitudes are given by the horrible Bessel functions. I have a pictorial representation of AM/FM that helped me understand the sidebands.

## Controlling the HF2LI Lock-in with Python

on 04.05.2011 at 16:45 by Lara Juricic on Blog of Jürg Schwizer
This blog entry contains a basic example how to communicate with HF2LI Lock-in using the Python programming language. This is achieved with an interface library of Zurich Instruments that transforms the ziAPI into a native Python interface.

## Controlling the HF2LI Lock-in with Matlab

on 03.01.2011 at 10:33 by Jürg Schwizer on Blog of Jürg Schwizer
Controlling the Zurich Instruments device directly with Matlab is extremely powerful for repetitive measurements and scripting. This blog entry explains a method to communicate with the ziServer directly from Matlab. This interface is very fast and thus well suited to record large data sets at high-speed.