# Loopstick (ferrite rod) antenna circuit model

A ferrite rod antenna circuit equivalent is usually given as so:

The numbers are made up, I didn't calculate the exact C you need to have to make it resonate at 1 MHz.

Here's a slightly more complicated model I found online that adds another implicit C, besides the variable one you add externally:

Here's my concern: no matter whether the LC is resonant or not, since it's in parallel to the "voltage source", it will be forced to take on its entire voltage.

I believe there should be a voltage division somewhere, so that if the LC (and the 10 Ohm wire resistances) are low impedance, most of the voltage will show elsewhere.

The above would work nicely.

I wonder what is the right circuit model for an ferrite rod (loopstick) antenna that demonstrates voltage division when the LC tank is out of resonance, and the voltage has to be captured outside of it ?

Is this a looptstick antenna as well?

• No, that's not the correct model by half a mile. Commented Oct 30, 2020 at 18:50
• Hey Andy, could you please help me understand what is the correct model? And where i can see the voltage division on it? All the models I saw online don't give you a voltage division, so it seems that whether the LC is resonant or not, the entire voltage will display across it, as it's in parallel to the "voltage source". Commented Oct 30, 2020 at 18:54
• A better way of putting it is that the magnitude of XC = XL at resonance. That's the more conventional way of stating the same thing. Or $\dfrac{-1}{j\omega C} = j\omega L$. Commented Oct 30, 2020 at 20:00