2/15/12 Started lab like instructed: cloned repo, tested board and got it's number (#0), then hooked it to the function generator to test it with the example VI. The example VI wasn't doing anything and Dr. Koch helped me get the error message that was being returned by the DAQ function. It was an invalid board number (which I had not inputted incorrectly) which appears to be a bug and was fixed by restarting LabVIEW.

"Pidgin oscillator" has only one hit on google. (http://www.ajpiii.us/pages/85930E/AJPIII-2714.html) which appears to be a nonsense paper. "Pigeon oscillators" has only one hit on google. (http://www.tksa.jp/v/v/M/rw6.html) which appears to contain neither of the words "pigeon" or "oscillators." These appear to be nonsense (yet perhaps grammatically correct) papers. other variations of the phrases have no hits on google.

A simple version of a point by point data acquisition program. It's almost identical to the example so far since it's so basic. took a git snapshot.

from the questions in the instructions mindmap: "What is the maximum frequency wave that you can reliably sample?" After discussing aliasing in class and recalling PHYS290, The maximum frequency that can be reliably sampled is 1/2 of the sampling frequency. Since the first very low frequency due to aliasing appeared at ~120Hz I conclude that the sampling frequency is around this value.
Near 60Hz I find another low frequency beat pattern that acts only as an envelope on the expected high frequency signal. After discussing this with Dr. Koch I believe this is near the nyquist frequency, or half the sampling frequency. This envelope is caused by the shifting of the sampling points from peak-peak to midpoint-midpoint.

I made a program to have the DAQ card do a (relatively) small number of samples at a high rate and return them to a graph. The max sampling frequency in this mode (with a low number of samples) is 8000 samples per second. This is enough to get not only non-aliased data from a 500Hz wave but enough to actually begin to see it's sinusoidal character with only 2 sharp point in a peak.

Pictures of the front and back labview panels were gotten from file->print... then exported to an HTML for both VIs I made.

Comments:

Maria's Comment: I also had to restart LabVIEW to fix the same problem! When I was reading the pidgeon links I was like "crap, I totally forgot this part of the lab-- what the heck is a pidgin oscillator?!" but then I remembered. Anyway, objective comment: you gave an informative explanation of aliasing and how it related to the data that you got which was quite insightful.

Anthony says

You now make up 50% of the pidgin oscillator hits and 100% of the pigeon oscillators hits. Also link to your repository from your notebook post. I tried poking around and it took me several clicks to get there. Rule of thumb with website navigation, make your users have as little clicks as possible to get anywhere on your site. Most likely people will come across your repository from your notebook and allowing them to get to the code quickly is vital.