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emitting antenna with 333pF tune capacitor in close range it is pretty much just normal induction

I wanted to build a simple antenna setup for a project at university. I send a sine wave in one antenna and I should receive it on the other.

If you look at the photos you should see that those antennas don't look like normal antennas but much more like a solenoid, that is the point they should pretty much behave like a solenoid except they are an antenna meaning they are designed to emit radio signals in my case at 457khz.

One of their features is therefore high directivity, if the receiving antenna is perpendicular to the magnetic field then no signal. This is where my setup clearly doesn't seem to be working.

The first anomaly is the tuned capacitor for my receiving antenna that I found to be around 30pF when it should actually be 75pF according to my calculations (the antenna's inductance is 1.6mH)

The second is that whenever my receiving antenna is about 1m away from the emitting antenna I am still receiving the signal but I lose directivity entirely. This led to my theory that the cables were actually the components working as normal antennas in my circuit and sending/ receiving a signal that decreased much less rapidly with distance than the one I received from the ferrite loop antenna. I was able to prove this theory by removing the antenna and to my surprise, I was still receiving the signal but a little less strong.

So I tried reducing the amount of cables to a bare minimum however this doesn't seem to have worked.

I would appreciate your advice.

(The project seeks to demonstrate the workings of avalanche transceivers so if this doesn't work then I won't be able to do lots of demonstrating)

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The directivity applies to signals from a distance of several wavelengths or more. You're working at a separation of ~0.001 wavelength. You have a transformer, not a pair of antennas.

The coil has a "parasitic" capacitance of its own effectively in parallel with it. You must account for that in a resonance calculation.

You're also seeing electrostatic coupling. To get a good null with a loop antenna, you often need electrostatic shielding.

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You need to build this circuit with solder and wire or on solder perf board. The cross capacitance between breadboard tracks can be as much as 10pf, the inductance asking the track can be high also along with contact resistance

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