Multisim and Ultiboard

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Multisim Vacuum Tube Models


Log ago I successfully did simulate several vacuum tube circuits in Electronic Workbench.
In Multisim 7 and 14 the tube models seem to be much the same, but I get no sensible results from simulation.
Is there a known problem with the models or am I doing something wrong?

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Could you expand on you mean by "no sensible results"? Is it values you are not expecting, or errors and warnings? 


Which tube models are experiencing the issues with? 


Are you using both MultiSim 7 and 14, with the undesired results occuring in both?




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I am using Multisin 7 and first tried simulating measurement of tube parameters for 12AX7 and 12AT7 by using DC Sweeps which I have earlier done in Electronic Workbench. The plate current remained very small regardless of anode and grid voltages. I then tried to simulate a simple audio amplifier but DC operating point came out with almost zero plate current. Transient simulation gave a small output signal.

I tried the DC sweep test with an evaluation version of Multisim 14, with same results.

Now I will try to reinstall EWB on an old Windows XP computer and recheck the old simulations.

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Yes, as explained by this post, it does seem that other people have experienced this issue beforehand.


There are recommendations to create your own model, until R&D is able to fix the existing models.


Thank you 

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Hi -- newbie here testing out the software for purchase. Has this been done yet?


And while we are on that subject... anywhere to get an EL-34 model?

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