Hello, I have set a signal with the VPWL. I am using voltmeter to see what kind of signal I have set up in VPWL.

If I am adding a 10k resistor under VPWL source, it is changing my signal which comes from VPWL source.

Could somebody explain me why it is happening? If I change any other parts they dont affect my VPWL source.



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Ohms law and Kirchoff. E=IR. The current that flows in the 10K resistor(pot) subtracts from the source voltage.

Hint, it is called an IR drop.

 

Just moved a ground to the correct place and everything is fine now.