Oscilloscope not reading frequency correctly
I apologize if this is a "nooby" question, but the oscilloscope seems bugged, at least for AC Voltage. I have the Pokit Pro connected to a wall outlet, (USA, 60 hz 120V RMS nominal).
Voltage reads fine, but frequency is borked. When I change the x axis (ms/div), the waveform doesn't change scale, but the freqency calculation does, (oddly, the period calculation does not). For example, if I put it on 100 us/div, it says my AC current is running at 2926.83 Hz, (and sometimes bugs down to 1951.22 Hz, seemingly at random). Simply changing the scale to 1 ms/div and it says 292.68 Hz, bugging andomly down to 195.12 Hz. Going to 10 ms/div and it says I'm doing 29.27 Hz, with bugs down to 19.51 Hz, (note these are all off by equivalent orders of magnitude). The waveform looks the same on the screen, regardless of zoom level.
Oh gosh, even worse, I seem to get new, different frequencies when disabling/renabling acquisition using the onscreen pokit button.
None of these values are close to the 60 Hz my AC current is running at (I'm in a major US city - I guarantee we aren't running at 30 Hz!). I've got the most updated firmware
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Just to pile on, I was playing with a square wave generator. Check out the period and frequency functions in these screen shots compared with the actual values of the square waves, (I used cursors to "measure" them).
1s square wave:
10 ms square wave:
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