11-21-2006 07:09 AM
02-26-2007 01:09 PM
Thanks for that input, Ingo, it solved my problem gettin a 12AX7 to swing in an RC oscillator.
I tried very hard to read the help file for my MS8.028, increased all sorts of stuff with no success, but your info was like the key...
Well it i is still interupted by "too small timestep" but last for a lot longer time. And its like Brad said, way too slow. I computer of today OUGHTA work faster.
I observed that the error comes when the risetime is steep and the voltage level high. Could it be that the calculations are not really prepared for hundreds of volts vs. short risetimes? And tubes has their similarities to FETs ´but not those high voltage levels. Unless we talk about hexfets, but they are like nore ON/OFF devices, right? Is there no chance that the Workbench tea, could concider looking at the calculations inner system for higher voltage levels / analog amplification factors / steep voltage level risetimes?
I made this RC oscillator to check an old guitar amp that had a defective tre,molo circuit. All components measured the right values, but I found that the third RC circuit, connected to the gate of the tube, didnt have a 60 degree phaseshift, so I suspected a leaking capacitor. Now that capacitor measured correct with a simple LCR meter, but leakage requires the old Sencore to be dusted off. B4 I did that I wanted to check with Multisim first what happens if I put a 1 MOhm resistor acroo one of the three RC links. It faded the oscillation excactly as in the guitar amp... I spended hours to make this, and I did it just to learn the workbench system better.
I really did. I found that I can add a comment to the circuit, describing hat changes had to be done in the simulation options.
Best regards,
Lars Ahlstrom
supertech, Sweden
10-15-2009 07:27 AM
03-16-2013 09:23 AM
i have a problem with the circuit in simulating. please help me with getting the output
03-16-2013 09:23 AM
i have a problem with the circuit in simulating. please help me with getting the output
03-19-2013 08:37 AM
Hi,
Delete the floating nets that you have there (9, 10, 18) and delete the voltage source (v4) that isn't connected to anything. Then if you are not using vdd, vcc, etc, delete those as well, if you are using them then connect them. This makes your simulation run properly. Try not to have so many unconnected components, if you don't need them then don't place them on the schematic.
Kind regards,