Orcad & tube library

[Antonix]

I have added a library of Tubes to Orcad 10.3.
I have runned simulation of a my circuit that contain a part of tube library
and I have error undefined subcircuit.

I have added the library as global and now I have errors of node floating.

How i can do ?

 

[pmillett]

Hi -

"Floating nodes" means that there are nodes with no DC reference to ground, or no connection. You need to add some reference - like a 1000 megohm resistor - to placate the simulator. Or, the subcircuit names aren't matched up with the symbol names so they are unconnected.

This might also be helpful (especially with undefined subcircuits, I always have issues with associating the models and pins correctly) if you haven't looked at it:

http://www.duncanamps.com/technical/pspicetubes.html

Pete

 

[Antonix]

OK.

I have solved the problem placing a 0 volt ground to circuit.

 

[Antonix]

Just a question on measures with Orcad.

I have to test the frequency response of a preampli circuit.
I have set AC VIN 1V and I have create a new simulation profile with AC Speep from 0.01Hz to 1Meg.

It's correct?

How can i measure the THD distortion?

I know that I create a Transient simulation centered to 1khz.