Many thanks for such excellent pointers to specific help features (and the caution on trying to overachieve a fairly simple task !).
You're correct in the one-point-at-a-time data acquisition. I've been lazy in simply taking one part of the prewritten driver and using that for reading the data continuously. I'll go back and examine the Fluke driver to look for more functionality. A most helpful item would be to limit the data to ~2 Hz. That's plenty for my needs just now. I'll look at the shipping examples to see if I can find a suitable example. Chris Nelson, one of our Minneapolis sales engineers, suggested building an array before running the Amplitude & Level Measurement VI. Apparently, the latter works on each chunk of data fed to it if one keeps the "original segments" size. Therefore, building an array of 1000 points or so would allow meaningful peak detection. In an initial trial of this, I found that I could collect 10,000 points at ~50 Hz and still process data continuously. However, the peaks reported were changing faster than expected: about every 2 seconds instead of every 200 seconds. I'll try this again with a pre-specified size of 10,000 points and see what happens.