I was wondering how would be the simpliest way to determine a capacitor value with the help of the scope. I connected a 2.2 uF capacitor in serie with a 990 Ohm resistor, negative port of capacitor to GND, positive port of capacitor to the resistor, and the other leg of resistor to the wavegen1 with a square signal at 20 Hz / 1V amplitude, the scope channel 1 being connected accross the capacitor. My first tought was to create a short script, calculating the rise time at 63% of the value of the voltage (1V) and then dividing this time by the resistor value. I'm not experienced enough to do that with script (it's probably very basic, if someone could give me some advice about this scripting, would be cool...). The other way I found was to play with the cursors ans manually place one horizontal cursor at 63% of 1V (0,63 V) and then to place a set of verical ones in order to determine the rising time from 0V to 0,63V...this is fair enough for me, I found roughly 2.07 ms, which corresponds to a capacitor value of 2.09 uF (I measured the capa at 2.09 uF with my multimeter). Then I saw that in the measurements there is a RiseTime calculation available...but I cannot figure how this value is calculated : it is from 0% to 100% of the signal, or it is from 0 to the triggering value which is set in the trigger value ? The value calculated gives 3.89 ms....
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Odolc
Hello,
I was wondering how would be the simpliest way to determine a capacitor value with the help of the scope. I connected a 2.2 uF capacitor in serie with a 990 Ohm resistor, negative port of capacitor to GND, positive port of capacitor to the resistor, and the other leg of resistor to the wavegen1 with a square signal at 20 Hz / 1V amplitude, the scope channel 1 being connected accross the capacitor. My first tought was to create a short script, calculating the rise time at 63% of the value of the voltage (1V) and then dividing this time by the resistor value. I'm not experienced enough to do that with script (it's probably very basic, if someone could give me some advice about this scripting, would be cool...). The other way I found was to play with the cursors ans manually place one horizontal cursor at 63% of 1V (0,63 V) and then to place a set of verical ones in order to determine the rising time from 0V to 0,63V...this is fair enough for me, I found roughly 2.07 ms, which corresponds to a capacitor value of 2.09 uF (I measured the capa at 2.09 uF with my multimeter). Then I saw that in the measurements there is a RiseTime calculation available...but I cannot figure how this value is calculated : it is from 0% to 100% of the signal, or it is from 0 to the triggering value which is set in the trigger value ? The value calculated gives 3.89 ms....
Thanks for your support
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