I got a situation: at the moment I am unable to access both channels for Keithley 2182A nanovoltmeter using LabVIEW. However, for some odd reason, while I cannot access the channels at once, LabVIEW does give me the ability to access channel 1 and the ratio between the two channels - from which I use those points to find channel 2.

However, again, because of my hardware, it appears I would need a minimum of two measurements (the minimum size of my buffer is of two), so I am wondering if the following decisions are sound with experimental good practices:

  1. Given that I get two measurements for channel 1 ($V_1$), I cannot just pick one of them (either at random or deliberately) so I calculate the mean of the two measurements and keep the mean measurement of $V_1$.
  2. Likewise, given two measurements of the Ratio of channels 1 and 2 ($\frac{V_1}{V_2}), I too calculate the mean and keep the mean measurement of $\frac{V_1}{V_2}$.
  3. And finally, I calculate the ratio between these two measurements to yield the mean of channel 2 ($V_2$).

Right now this is just a draft, proof-of-concept so I can do some measurements to teach myself basic lab techniques. However, I also know, from experience, that what I just described sounds like really bad in terms of error propagation. For instance, I think I can able to stand by steps 1 and 2 in terms of error propagtion, but the third step, the ratio, I am wondering: how bad is this ratio measurement in terms of error propagation?

Also, any books, papers, etc about experimental techniques in electronics would be greatly appreciated!


  • 2
    \$\begingroup\$ Just fix LabView - don't compromise on stuff. \$\endgroup\$
    – Andy aka
    Feb 27, 2020 at 20:51
  • \$\begingroup\$ Thanks for the feedback. I just want to add: I have tried, but have been unsuccessful on this. However, I also have to add: I am coming back to LabVIEW after 2+ years hiatus. \$\endgroup\$ Feb 27, 2020 at 20:53


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