• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Triode/Pentode Loadline Calculator

Hi
I'm working on a program to simulate loadlines. Here's a link to the first version:

Triode Loadline Simulator v.0.2

The list of tubes is constantly updated. This is a simple javascript, so the program can be run without any installation :) and can be run by most web browsers. To change the parameters (operating point etc.) use triangular indicators that can be dragged using the mouse.

I checked the behavior of the program using different browsers. There is no problem with new versions of browsers. Unfortunately, Internet Explorer version 8.0 and earlier can not cope with it. In a newer version of IE for example. 11.0 this problem does not occur.
 
Thank you for your interest in the subject.
The simulations are carried out on the basis of the Koren's model - the same as often used in Spice modeling.

Improved vacuum tube models for SPICE, Part 1

So the program can simulate any triode provided that its parameters (five values: mu, ex, kp, kg1, kvb) are known.
According to your suggestion, after testing phase I will add the ability to specify parameters of any triode by the user. I hope I will do it in few days.
In the meantime I will be adding new models. I calculate Koren's parameters using anode characteristics and javascript program implementing genetic algorithm.
I will be grateful for any comments on whether the characteristics are well matched
 
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Would be nice if one can define a load line around an operating point... drag the load line pivoted at the operating point. Then you don't have to be limited by Va, eg. a ccs load application.

Would also be nice to be able to import the tube characteristics from something like the utracer.
 
Would love to see one for GM70, extending past 1000v :yummy:
I need to refine the genetic algorithm, as there are large discrepancies for voltages above 1kV. Mayby the Koren's formula is not suited for large anode voltage ranges - I hope not, and it is only the matter of genetic algorithm parameters.
Of course, there is no problem if you already have Koren's parameters for GM70 - I'll add it to the tube list.

Would be nice if one can define a load line around an operating point... drag the load line pivoted at the operating point. Then you don't have to be limited by Va, eg. a ccs load application.

Would also be nice to be able to import the tube characteristics from something like the utracer.

With this shifting a lodaline is a cool idea :). I append it to the list of options to be added to the program. I have "uTracer" tester :). It is perfect :), but stores the results as a table of measurement points, not a tube model parameters :(. Parameters have to be calculated independently. So, this useful option can be added when i finish testing the procedure for calculation of tube parameters based on the results of measurements (see for axample the problem with voltages above 1kV). The algorithm, I use at present is already adapted to import data from uTracer.
 
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This is very cool indeed. I've been playing around with it for a bit. It's fun. One question, though...

For ECC83, when I shift parameters so that the supply voltage is 360V (the maximum allowed), Rp is 220k, Ug is -1.2V, Ia is 0.98mA, the calculator shows H2 as 0.000% (!!). However, if I shift the operating point so that Ug is 0.87mA and Ug is -1.5V, H2 is 2.405%.

Is that reading of 0% H2 distortion caused by the sim going crazy due to grid current?
--

Also, I agree that the maximum allowed supply voltage should be raised for most of the models. For instance, the ECC88 is limited to +180V. I've seen +300V used, routinely.

Can I request 6N6P, 5687 and 6SN7 (6N8S, 6H8C)?
 
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Thank you for your feedback. I fixed procedure of calculating h2 (I did not take into account that the value of h2 can be less than zero, and I unnecessarily replaced negative values with zeros). I increased the Vmax for ECC88. I also added 6SN7GT.
Because the simulation results depend on the accuracy of the data points, below I enclosed the data that I used (the format used in the uTracer) for verification.

6SN7GT

Code:
Point    Curve     Ia (mA)        Is (mA)       Vg (V)          Va (V)         Vs (V)         Vf (V)
1        1          1.65           0             0.0             20.00          500.00         6.30
2        1          3.50           0             0.0             40.00          500.00         6.30
3        1          5.75           0             0.0             60.00          500.00         6.30
4        1          8.30           0             0.0             80.00          500.00         6.30
5        1          10.95          0             0.0             100.00         500.00         6.30
6        1          13.65          0             0.0             120.00         500.00         6.30
7        1          16.75          0             0.0             140.00         500.00         6.30
8        1          19.55          0             0.0             160.00         500.00         6.30
1        2          0.70           0             -2.0            40.00          500.00         6.30
2        2          1.65           0             -2.0            60.00          500.00         6.30
3        2          3.20           0             -2.0            80.00          500.00         6.30
4        2          5.35           0             -2.0            100.00         500.00         6.30
5        2          7.90           0             -2.0            120.00         500.00         6.30
6        2          10.50          0             -2.0            140.00         500.00         6.30
7        2          13.15          0             -2.0            160.00         500.00         6.30
8        2          16.00          0             -2.0            180.00         500.00         6.30
9        2          19.00          0             -2.0            200.00         500.00         6.30
1        3          0.70           0             -4.0            80.00          500.00         6.30
2        3          1.70           0             -4.0            100.00         500.00         6.30
3        3          3.25           0             -4.0            120.00         500.00         6.30
4        3          5.25           0             -4.0            140.00         500.00         6.30
5        3          7.55           0             -4.0            160.00         500.00         6.30
6        3          10.15          0             -4.0            180.00         500.00         6.30
7        3          13.00          0             -4.0            200.00         500.00         6.30
8        3          15.90          0             -4.0            220.00         500.00         6.30
9        3          19.05          0             -4.0            240.00         500.00         6.30
1        4          0.85           0             -6.0            120.00         500.00         6.30
2        4          1.85           0             -6.0            140.00         500.00         6.30
3        4          3.40           0             -6.0            160.00         500.00         6.30
4        4          5.40           0             -6.0            180.00         500.00         6.30
5        4          7.65           0             -6.0            200.00         500.00         6.30
6        4          10.20          0             -6.0            220.00         500.00         6.30
7        4          12.85          0             -6.0            240.00         500.00         6.30
8        4          15.80          0             -6.0            260.00         500.00         6.30
1        5          1.00           0             -8.0            160.00         500.00         6.30
2        5          2.05           0             -8.0            180.00         500.00         6.30
3        5          3.60           0             -8.0            200.00         500.00         6.30
4        5          5.50           0             -8.0            220.00         500.00         6.30
5        5          7.85           0             -8.0            240.00         500.00         6.30
6        5          10.20          0             -8.0            260.00         500.00         6.30
7        5          12.95          0             -8.0            280.00         500.00         6.30
8        5          15.70          0             -8.0            300.00         500.00         6.30
1        6          1.05           0             -10.0           200.00         500.00         6.30
2        6          2.15           0             -10.0           220.00         500.00         6.30
3        6          3.65           0             -10.0           240.00         500.00         6.30
4        6          5.65           0             -10.0           260.00         500.00         6.30
5        6          7.90           0             -10.0           280.00         500.00         6.30
6        6          10.00          0             -10.0           300.00         500.00         6.30
7        6          12.50          0             -10.0           320.00         500.00         6.30
1        7          0.55           0             -12.0           220.00         500.00         6.30
2        7          1.15           0             -12.0           240.00         500.00         6.30
3        7          2.30           0             -12.0           260.00         500.00         6.30
4        7          3.78           0             -12.0           280.00         500.00         6.30
5        7          5.60           0             -12.0           300.00         500.00         6.30
6        7          7.65           0             -12.0           320.00         500.00         6.30
7        7          9.90           0             -12.0           340.00         500.00         6.30
8        7          12.15          0             -12.0           360.00         500.00         6.30
1        8          0.62           0             -14.0           260.00         500.00         6.30
2        8          1.30           0             -14.0           280.00         500.00         6.30
3        8          2.45           0             -14.0           300.00         500.00         6.30
4        8          3.95           0             -14.0           320.00         500.00         6.30
5        8          5.80           0             -14.0           340.00         500.00         6.30
6        8          7.60           0             -14.0           360.00         500.00         6.30
7        8          9.95           0             -14.0           380.00         500.00         6.30
1        9          0.70           0             -16.0           300.00         500.00         6.30
2        9          1.48           0             -16.0           320.00         500.00         6.30
3        9          2.60           0             -16.0           340.00         500.00         6.30
4        9          4.10           0             -16.0           360.00         500.00         6.30
5        9          5.90           0             -16.0           380.00         500.00         6.30
6        9          7.85           0             -16.0           400.00         500.00         6.30
1        10         0.77           0             -18.0           340.00         500.00         6.30
2        10         1.55           0             -18.0           360.00         500.00         6.30
3        10         2.62           0             -18.0           380.00         500.00         6.30
4        10         4.00           0             -18.0           400.00         500.00         6.30
5        10         5.87           0             -18.0           420.00         500.00         6.30