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I just created a dead simple circuit.

The switch is set to close after 1 second. I'm trying to run the time simulation for 2 seconds with an interval of .1s, measuring the voltage at the input of R1.

There is no progress, and no error messages that I can see. All I get is a blank screen like this.

Any ideas on how I can debug my circuit to make the simulation work?

Hi @maurin, your circuit is currently private so we can't see it. Can you click the "Make public" button on your circuit page so we can take a look?

Sorry about that. It is now public. Thanks for taking a look.

Always make sure every component lead goes somewhere, under all conditions. When your switch is open, the gate of the fet is floating. That confuses the number-crunching code, as the voltage there is going to be undefined.

Try putting a 100,000,000 ohm resistor from there to ground. That may help.

Alright, I put the 100M ohm resistor, and the simulation works now. Thanks for clarifying the need to connect every lead.

Well, I'd no idea that in CL, simply naming a net +5V invoked a 5V source.

Hmmm. What if I have a 1V source and name the +ve end of it +1V? Does CL complain about having two voltage sources in a loop? Yes it does.

Careful with those netnames ...

This is OK:

but this is broken:

Naming the net 1V fixes the brokeness.

@maurin,

Don't forget that if you update a schematic that you have linked into a forum post, that schematic will change which may lose the context of the original question or informative posting.

It may be better to keep the original and save the modifications under a different name

:)