The Romer-Lewin ring with inductors (part 3 preview)
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- Опубліковано 22 сер 2024
- A sneak preview of what will be part 3 of the inductive Romer-Lewin ring series. (Apologies, but due to certain technical difficulties I cannot produce videos longer that 5-6 minutes.)
Here I show the voltages measured right across the two lumped inductors, getting RMS readings that, once corrected for the UT139C bandwidth, sum up to a value that is essentially the EMF (but it's actually higher, as we shall see when treating the case of generalized impedances.)
The correction factors that allow me to use the UT139C at 4 kHz are: 2.12 for voltages under 40 mV (readings under about 20 mV) and 2.06 for voltages above 40-50 mV (readings above 20-25 mV.)
Therefore, when I read 8.94 mV on the UT139C, the actual measure should be 8.94*2.12 = 18.95 mV. This is in agreement with what the UT661E reads when in the same position, that is 18.99 mV.
Conversely, when I read 40.37 V on the UT139C, the corrected measure is 40.37*2.06 = 83.16 mV. In good agreement with what the UT61E reads when in the same position: 83.81 mV.
Considering the tolerances of the instruments, we can confidently use the UT139C to measure voltages at 4 kHz ( in the range 0-200mV) with a simple multiplicative correction.