Guidance on resonant freq scanning circuit

chadj2 said:

I am not exactly sure if the inductance change could be specified that precisely.
I would say the inductance change would be quite random.
limiting the range of inductance range

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So the search algorithm would involve. . .
triggering a search if the off-resonance condition is detected within a certain tolerance and
searching down to a low limit and
searching up to a high limit and
if resonance is not reestablished, outputting an error signal.

If you want to stay in the analog domain, implementing this algorithm could be tricky.

An eight-to-one change in resonant frequency requires a huge 64-to-1 change in inductance, unless the series capacitance is also changing. How do you intend to change the inductance over that range?

I was planning on keeping the load very light on the secondary winding by PWM. I am realizing that this is more challenging than I first thought, but I will keep looking. Thanks

Chad

What is your understanding of inductance? And, as I said before, how do you plan to vary it?

I plan on varying it by by controlling how much current I am pulling out of the secondary winding around that inductor. It is basically going to be acting like a transformer. What I have seen as I have played with resonance circuits is that when I put a resistor on the secondary of the inductor in the tank the resonance frequency changes. So that is all I am trying to do. I am just trying to find out a way to easily track the resonance frequency. I know I can do it manually but I was wondering if I can do it automatically. It is looking extremely hard from what I am hearing and what I have read.