Mosfet Hartley Oscillator.

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Lightium

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I am having trouble designing a Hartley oscillator using Mosfet's because Mosfet's a new to me still. All I know is that Q/I= switching time. I had to change the extension on the file, EOL won't take an sp3 file?

 

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So I figured out that:
L1+((N2*flux1)/I1) / L2+((N1*flux2)/I2) = gain

I'll see how this plays out when I get back to my desk.
 
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So from the equation if the tank circuit is symmetrical gain will be 1. If L1 is higher then L2, then gain will be > positive 1.
 
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The key variable for MOSFETs is the OFF threshold Vgs(th)=Vt @100uA and the ON resistance RdsOn at Vgs >> 2Vt in between controlled by (Vgs-Vt)^2.

Here I bias each transistor with some threshold just using a DC battery then sweep with adjustable AC to compare how they differ yet similar. https://tinyurl.com/2la4ml22 for voltage controlled quadratic current.



I plotted all the input and output voltages, currents and power dissipation. To choose this input DC bias, this can be done by a large series R for a load and connect input to output. But then if you know the characteristic equations, you don't need to do this.

Any questions?
 
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Define what you expect on the output exactly with impedance at 75kHz?, then what is needed on Vgs to get that. Your gate bias and excess of inductors are problems.
 
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