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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?

Screenshot at 2023-04-30 01-56-19.png
 

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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.

1683222176220.png


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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Of course with Vgs=0Vdc it won't oscillate.
 
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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