Hey!
I am starting with electronics and was using Multisim for simulations. I am following Make - Electronics book.

Multisim is quite nice but now i found a circuit that will not work there.

The problematic circuit:


Knowing that people like different simulators i would like to ask you for a favor:
Could you draw this same example in your favourite simulator and report back here what happens.


From the results i would like to find simulator that works with these simple circuits.


Thank you very much!

 

Why does this circuit not work you in your simulator? By the way what is your source for this circuit. The circuit do not look coorect as shown. The resistor vaules will ensure that the LED is off no matter with 6 volt DC as supply voltage

 

Multisim goes crazy, sometimes giving errors other times just stopping the capacitator charging.

There is a thread in multisim support forums about this and some guys modified it alot to get it working. But i would like it without modifications because it is working in real life why not in simulator?


Edit: this circuit is direct screenshot from "Make-electronics"

 

Does simulation allow input for "put"?

 

Hello,

Look at the bottom of the following page for an explenation of the PUT:
http://digilander.libero.it/nick47/thup.htm

As the page is in italian, I used google to translate it:
https://translate.google.com/transl...gilander.libero.it/nick47/thup.htm&edit-text=

Bertus

 

I made picture of multisim. This is how it gets stuck and nothing happens anymore:

 

Just about works as is in LTspice, depending on choice of LED model. Works better, and less dependent on LED type, if 15k is replaced by higher value, e.g. 22k.

 

Just about works as is in LTspice, depending on choice of LED model. Works better, and less dependent on LED type, if 15k is replaced by higher value, e.g. 22k.

Just curious... Where did you get your PUT model?

 

Just about works as is in LTspice, depending on choice of LED model. Works better, and less dependent on LED type, if 15k is replaced by higher value, e.g. 22k.

Thank you for the results!
I tested 22k in multisim and it is working also. Quite small drift from the real circuit so i think it is acceptable.

However still wondering why it is not working as is and how can LED type make any difference here?

Thanks!

 

Just curious... Where did you get your PUT model?

Free download from Yahoo LTspice User Group.

 

still wondering why it is not working as is and how can LED type make any difference here?

Transistor gain? Junction forward voltage drop? Leakage current? ....?