VLF null and frequency

[manhunt47]

What is the exact problem?
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Thankful
In the settings section, I fixed this problem and changed it completely

[manhunt47]

An interesting subject I encountered was the Fisher F75, because the circuit structure is similar to resonant series, but its signal response is different.
An interesting point in this circuit is that the resonance frequency Rx is quite similar to that of Tx
I found information from the map and signals from this device from the MD4U forums, which I put here.

[manhunt47]

As you can see, the PREAMP section and the loop structure of the DD type are displayed, and the values of the inductances are also known.

[manhunt47]

Now I simulate the PREAMP circuit of the F75 and answer the frequency and phase response.
As you can see, in the Vin signal the amplitude and phase changes in the TX frequency range are small and not too sharp.



Phase Response and Signal Domain Vin


Phase Response and Signal Domain Vout

As can be seen, the Vout signal from the Vin signal at a frequency of Tx is 20 degrees behind.