VLF null and frequency

[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.

[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]

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]

What is the exact problem?
If you're asking about changing the font or the size and color then there should be a toolbar that allows you to do this.
If the toolbar is not there, then it must be a problem with your browser.

Thankful
In the settings section, I fixed this problem and changed it completely

[Qiaozhi]

Hello Qiaozhi
Admin if possible help me
Previously, I could write the font and color of the book and even put the sticker, but now that toolbar does not exist
My toolbox does not exist to change fonts and more

What is the exact problem?
If you're asking about changing the font or the size and color then there should be a toolbar that allows you to do this.
If the toolbar is not there, then it must be a problem with your browser.

[manhunt47]

Please read the forum rules -> Basic Rules of the Forums
and make your posts in English.

Hello Qiaozhi
Admin if possible help me
Previously, I could write the font and color of the book and even put the sticker, but now that toolbar does not exist
My toolbox does not exist to change fonts and more

[manhunt47]

I do not understand the language of your writing, especially on the image

[pustareka]

[Qiaozhi]

NAUTILUS ТХ и CХ имеют по 4.2 Ом, толщина провода 0.45мм - одна пара хвостов соеденена вместе и кинута на землю, вторая пара на платку в параллель им пленочный кандер неизвестного номинала. РХ имеет сопротивление 26 Ом толщина 0.3 мм, в параллель РХ стоит кандер 22Н. Корпус катушки изнутри промазан графитом и обе половинки корпуса. TX= 4.2 R WIRE 0.45mm CX=4.2 R WIRE 0.45mm RX = 26 R WIRE 0.3mm C_RX=22n Transistori 2N5088 GRAFIT SHILD CASTOTA NAUTILUS F 13965 Hz FAZA TX/RX = 0 GR.

Please read the forum rules -> Basic Rules of the Forums
and make your posts in English.

[pustareka]

NAUTILUS ТХ и CХ имеют по 4.2 Ом, толщина провода 0.45мм - одна пара хвостов соеденена вместе и кинута на землю, вторая пара на платку в параллель им пленочный кандер неизвестного номинала. РХ имеет сопротивление 26 Ом толщина 0.3 мм, в параллель РХ стоит кандер 22Н. Корпус катушки изнутри промазан графитом и обе половинки корпуса. TX= 4.2 R WIRE 0.45mm CX=4.2 R WIRE 0.45mm RX = 26 R WIRE 0.3mm C_RX=22n Transistori 2N5088 GRAFIT SHILD CASTOTA NAUTILUS F 13965 Hz FAZA TX/RX = 0 GR.

[manhunt47]

The tx coil inductance I'd a known commodity. 14khz @ x capacitance, I can't remember, but I did check it.
Now check out the Nexus. I t had balanced TX and Rx at unity resonance.
Cheers, I be back, after I drink some more coffee.

I did not find any schematic information about nexus devices.
I even saw several forums.

[dbanner]

The tx coil inductance I'd a known commodity. 14khz @ x capacitance, I can't remember, but I did check it.
Now check out the Nexus. I t had balanced TX and Rx at unity resonance.
Cheers, I be back, after I drink some more coffee.

[dbanner]

I was curious to check the frequency response of the Nautilus circuit
But since the coil inductance is unknown, but the transmitter's only frequency is specific, and it was also said that the receiver's resonant frequency is the same as the transmitter, so I first calculated the amount of INDUCTANCE coil RX and then simulated it.
Of course I did not know the type of transistor.

[ATTACH]45567[/ATTACH][ATTACH]45568[/ATTACH]

Your tests confirm my logical observations, though I never pursued it. It is precisely what I would have expected.

[manhunt47]

Hello
Someone can help me
Previously, I could write the font and color of the book and even put the sticker, but now that toolbar does not exist.

[Koala]

coil doesn't settle down for the first hour detecting ?

https://www.youtube.com/watch?v=oMwSMDK9__U&t=0s&list=PLpEdWf-sVlbgBKmT6uS0Avdi2t9b-tWhG&index=2


like the idea of stereo audio