Hello
It seams that my HPS140 needs calibration. It shows wrong results, that makes me sad.
E.g. it shows 434.7Hz instead 440Hz (t=0.2ms/div) and 96mV instead 100mV. Voltage measurement is different in different V/div selection, but this because of biting, I guess. E.g. at 2V/div online result is 5.38V, on hold I have 5.00V at 2V/div and 5.336V at 1V/div? At that time two independent multimeters shows 5.15V. I think at 1V/div 5.168V is closer to 5.15V then 5.336V.
But frequency measurement is much more preferable for me then voltage.
Is it any way to calibrate it, using signal generator or another oscilloscope?
I think these values are very normal! 434.7 compared to 440 is just 1.2% difference! As most of the other values the HPS140 can measure can deviate within +/- 2.5%, this will be a very good result.
The voltage measurements look quite OK. Don’t forget that this is an 8-bit device. Always use a V/div setting that gives an as large as possible signal.
The resolution of the frequency measurement is limited by the screen resolution. For higher accuracy, you require a frequency counter.