1. Physics 434 Module 5 1 Module 5 – Serial devices using VISA An application to measure capacitance

2. Physics 434 Module 5 2 Serial interfaces RS232 HPIB  GPIB VISA USB

3. Physics 434 Module 5 3 The Agilent (nee HP) 43310A

4. Physics 434 Module 5 4 Frequency domain: A low-pass RC filter.

5. Physics 434 Module 5 5 Time domain (à la Module 4) Apply a square wave, measure response, charge or discharge May not seen serial device; at least use Agilent to measure resistor

6. Physics 434 Module 5 6 Main points (see the doc) Understand the Agilent or Textronix Build the RC circuit (you might want to use the signal generator and scope to get a quick understanding). Two options (or your own ideas) Frequency domain: Get and use the SweptSineGenerator (in the Module5 llb). Generate the sweep. Time domain: use the Vi from Module 4 to create a long pulse Analysis either inline, or write out the data to fit Generate a final vi to calculate the frequency.

7. Physics 434 Module 5 7 Fitting with Levenberg- Marquartd.vi This VI has a nice interface to specify a model. It is a cluster of 3 items: the formula, an array of parameters to fit, (a,f) and the independent variable (x). Package it into a subVI, inputs X, Y, “Initial Guess”, output “Best Fit” and “Best Fit Coefficients” (really parameters). Make a LED light up if there is an error. The graph comparing data with best fit can be generated here (But note that this is already done: there is a fit_bode.vi you can use)

8. Physics 434 Module 5 8 The final project We will be coming around to discuss this. See the list of suggestions on the web site Can be individual or joint: if joint, the individual contributions need to be specified (specific sub-vis, for example.) It will still be a joint grade. Make a proposal, perhaps by e-mail. I want to have a title and a short description.