HarryNNelson

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  1. Thanks JColvin! Presumably WaverFormsLive will just get changed in the "hot copy" we download eventually. As long as I'm here, a similar effect in the Bode plot... I was thrown off by the label "Amplitude (dB)" in attached. It appears to be "Amplitude^2", really... a factor of 2... maybe a better label might be "Power (dB)" or "Energy (dB)". Having said that, we've had fun making the Bode plot work for resonant circuits... need to divide down the AWG. best, Harry Nelson
  2. Hi, for the captures below, first channel 1 and then channel 2 see a 1Vpp (500 mV amplitude) sine wave at 5.501 kHz... the Ch1 FFT looks right, but maybe the vertical scale on Ch2 is not accurate... it is labeled "Ch1" and the range is -1000mV to +1000mV, peak location not plotted at 500mV for Ch2... but in both cases the little tag reads the appropriate amplitude... for a while this has confused me as to what normalization the FFT used... pretty sure it is amplitude, not pp or RMS... but perhaps the display for Ch2 needs some analysis... best, Harry Nelson
  3. Hi, 2 of my TAs have found that their OpenScopes have the grounds associated with Ch1 and Ch2 with wires that are black with a white stripe. Since the inputs are not differential/floating, doesn't matter much, but as we teach, some of the students (at home due to pandemic) are likely to get confused. Would be interesting to learn if this color change was characteristic of a particular production run, and, if there are other known issues with that run. best, Harry Nelson
  4. Yes, @JColvin, the web version works fine. Haven't tried the offline version. thanks again, Harry
  5. Thanks, maybe I have started to understand. Probably I dug the WaveForms Live .html out of the install, a "local" version, because it didn't occur to me to grab it from a link on the web at each start of a session... I'm just too old. Will check out later today. best, Harry
  6. Thanks... I don't really know what the difference between a "local copy" and other copies is, or how I'd end up with a "local copy"... in any case, I'll download from that site... I didn't keep a log of my steps to get here... best, Harry
  7. Hi, I don't see the "Bode plot" tool up in the upper right corner of the display window... seems to be 6, vertically... (1) FFT (2) expand to full time base (3)recenter time base (4)download (5)Pinout (6)full reset Firmware version is 1.301.0, says that is latest in configuration, macOS High Sierra, 10.13.6. thanks, Harry
  8. Thanks, yup, that seems to be the documented way of doing it... the RMS when there is a significant non-zero mean isn't particularly useful though, particularly when the mean is rather larger than the standard deviation, since they add in quadrature. The RMS just ends up being almost exactly equal to the mean. The standard deviation is a lot more useful... quantifies noise, for example... ripple on a DC voltage source. But I agree that the official RMS is what is given, that is consistent. I'd suggest considering changing to the standard deviation. all the best, Harry
  9. Greetings... Waveforms Live and OpenScopeMZ have generally worked very well for me. One small problem is the RMS calculation in the Math Menu. It seems not to subtract off the mean value... seems to be sqrt((1/(N-1)) (Sum (V^2))), should be sqrt((1/(N-1))(Sum((V-V_mean)^2)))... anyone else notice this? I work around by outputting the .csv file and computing there. Thanks for any help for feedback.