AV multiband VLF receiver

[ikumi5]

hello ts
antenna=? (how many turns (Approximately ))
sorry i have no L meter

thanks and regards

[mustefa ubram]

Correction circuit WITH 3914

[iron1944]

WM6 great master help me?
This large square coil circuit instead of 5 khz alıcı.Ben ferrite rod diameter of 1 cm length 20 cm
use wire diameter and number of turns of the coil wound on the rod lazım.Ferrite how should it be?
Thank you.

http://k1306.hizliresim.com/1b/u/pm3y5.jpg

[WM6]

Originally Posted by iron1944

WM6 great master help me?
This large square coil circuit instead of 5 khz alıcı.Ben ferrite rod diameter of 1 cm length 20 cm
use wire diameter and number of turns of the coil wound on the rod lazım.Ferrite how should it be?
Thank you.

http://k1306.hizliresim.com/1b/u/pm3y5.jpg

It depend of ferrite rod characteristics which are not known..

You can use the same wire diameter. First wind 50 testing turns on your ferrite rod and measure inductance. Out of this you can calculate total inductance bzw. number of turns.

For 5kHz preference:

your coil inductance have to be 1mH

and C1 1uF (instead of 0.02uF as on schematic).

[liubing]

Help PI detector project, 50X50cm can detect 5m, with 1x1m coil, which help me? Discrimination is not required,

[WM6]

Originally Posted by liubing

Help PI detector project, 50X50cm can detect 5m, with 1x1m coil, which help me? Discrimination is not required,

You probably already know who would help you dig at 5m?

[liubing]

I look forward to explore 5M

[WM6]

Originally Posted by liubing

I look forward to explore 5M

Good, pinpoint at 5m is +-2m. So you need to dig hole 5x4m. And not only one, there can be in hole some metallic ore only. Probably no problem for you?

[liubing]

I am here 20X20CM reach 2.5M, then undetectable basic thing that is buried very deep, but there are countless treasures underground, so I am committed to increasing depths

[liubing]

Who can provide the increasing depths of effective programs? Interested parties are welcome to explore a friend

[WM6]

Sorry, but I will left all those countless treasure to you.

Not interested in 5m (empty) hole digging adventure.

[mahditala]

Friends does not work on my device

[WM6]

Dear mahditala. This is a toy only, to play around, with intention to practice some basic electronic building and in hope to prevent you from buying highly overpriced crap as Mineoro, OKM etc., which does not work also.

And what is not working on your device, you got no sound out of it, or it cannot point you to golden treasure?

[edward]

Originally Posted by WM6

Dear mahditala. This is a toy only, to play around, with intention to practice some basic electronic building and in hope to prevent you from buying highly overpriced crap as Mineoro, OKM etc., which does not work also.

And what is not working on your device, you got no sound out of it, or it cannot point you to golden treasure?

Hi wm6

I am working on this vlf receiver

I dont have ferrite rod 20 cm long in avilable

What do you reccomend me??

Can i use from shorter ferrite???

[WM6]

Originally Posted by edward

Can i use from shorter ferrite???

You can use ferrite from an old transistor MW radio.


As long you maintain ferrite antenna at 57mH, by proper number of turns,
band limits with proposed C values will be OK.


Answer on how to establish proper number of turns, you can find here.


http://www.longrangelocators.com/for...5&postcount=30

[edward]

Originally Posted by WM6

You can use ferrite from an old transistor MW radio.


As long you maintain ferrite antenna at 57mH, by proper number of turns,
band limits with proposed C values will be OK.

Answer on how to establish proper number of turns, you can find here.


http://www.longrangelocators.com/for...5&postcount=30

You mean if i changed the length of the ferrite i need to set the inductance to 57 mH by changing number of turns
Ok
About vu meter: 1 mili amper full scale does not exist how can i measure the signal strength?? (Except using leds)

[WM6]

Originally Posted by edward

You mean if i changed the length of the ferrite i need to set the inductance to 57 mH by changing number of turns
Ok

By various length or diameter or Ferrite brands (composition) you need

to set inductance to 57mH by proper number of turns.
Otherwise you need to recalculate all bad capacitors.

Originally Posted by edward

About vu meter: 1 mili amper full scale does not exist how can i measure the signal strength?? (Except using leds)

Stay with in schematic proposed LED indicator.
You do not need 1mA VU meter.

[edward]

Originally Posted by WM6

By various length or diameter or Ferrite brands (composition) you need

to set inductance to 57mH by proper number of turns.
Otherwise you need to recalculate all bad capacitors.







Stay with in schematic proposed LED indicator.
You do not need 1mA VU meter.

How can i recalculate the capacitors?

[abdou2014]

the antenna of my gold gun is 59mH

https://ibb.co/mMNpy0

what can I have with this schematic ???

[edward]

Originally Posted by abdou2014

the antenna of my gold gun is 59mH

https://ibb.co/mMNpy0

what can I have with this schematic ???

This is gold gun???

The gold gun includes tow 3.5 cm ferrite rods with 337 turns wire 0.2 mm from center of each rod

[abdou2014]

Mr WM6 Is the transmitter essential ?
where should the transmitter be fixed ?

[WM6]

Originally Posted by edward

How can i recalculate the capacitors?

Corrections my typo in previous post: Not " all bad capacitors." but "all band capacitors".



You can use one of online LC tank calculators with known variables L and frequency band.

I suggest you not to change C value, but to establish L of ferrite antenna at 57mH by proper numbers of turns.

[WM6]

Originally Posted by abdou2014

Mr WM6 Is the transmitter essential ?
where should the transmitter be fixed ?

Of course it is essential.


TX is your separate multi frequency device or existing (military) sender working at about 30kHz.

RX to TX should be oriented like this example with Gold Gun:

[abdou2014]

is this receiver capable of detecting the earth's magnetic field ?

[WM6]

On lower band, if you move sensor to fast.