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Topic: Voltage Divider & Voltmeter help (Read 7 times) previous topic - next topic



I did as your diagram outlined..and it works 'perfect'...

I even left the meter included when I hooked up the Arduino just to keep an eye-on readings.

SO goes back to..  I must be doing something wrong on the breadboard set-up?

here is a pic:

thanks for the help guys!.


Your 4k7 resistor is shorted out because you have both ends in the same row of the breadboard.
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got ya!.   :)
I have also corrected my diagram to show my error/fix

I am now going to go back and change out the resistors to match for 8.4v input.

Thanks to everyone for your help.   :D


So you've had 7.4V going into your analog pin all this time?  That's not good.
Does the chip feel warm when powered up now? If so, you likely blew the pin.
And if not, it may be partly damaged and fail on you eventually.

"is there a way I can meter my resistors? to accurately find out the values?"
Yes, just measure them with your multimeter. You have gold bands on the resistors? I think that's 10% tolerance (maybe 5%, I'm  not sure which).
If you know the actual values, you can use that in your math for more accurate results.
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Runaway Pancake

I would just add: Ohmmeter your resistors out of circuit,
Never* put an ohmmeter on a live/powered circuit.

(* For your meter's sake.)
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