Need help, Series RLC resonance circuit, not getting high voltage

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kougou
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Hi all.

I am currently building a series RLC circuit as a magnetic field transmitter. Because I want to have a strong magnetic field, I need high voltage by making the circuit at resonance.
Here are the parameter I used:
L:1.15mH
R: 50 (internal resistance from functional generator )+ 0.58 (from inductor)
C: 1 nf.

Using equation the equations w0=1/sqrt(LC), and Vc= Q Vs= 1/R*sqrt(L/C)*vs,
w0=148kHz, and Q=21.2V, and Vs=5V(square wave), so voltage across capacitor should be around 108 V rms.

But using the oscilloscope, the V pk-pk voltage measured is only about 60 V, Vmax is about 20V.

So, why am I not getting the calculated result?
 

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Simon Bridge said:
A square wave is not a pure signal is it?
What happens when you put a range of frequencies into a resonator?
It could also be that your voltage source cannot provide more than 20V.


Thank you for your reply
The source is square wave, and it's jumping from 0 V to 5V. But the resonance voltage across the capacitor should be 5*Q=108V rms. One possiblity is that the functional generator doesn't provide that much current.
Besides that,
I don't know why my circuit doesn't know. Do you have any idea.