Very low frequency circuit very good
 

:):)
Very low frequency circuit very good
Very sensitive to static electricity and electromagnetic fields
Lightning strikes may harm him
It has an insulation feature, but I don't know how
Possible help from engineers, such as developing the antenna
https://4.top4top.net/p_1438qj6261.jpg

The device is completely stable
The TV senses from 1/2 meter

https://4.top4top.net/p_1439pnwh31.jpg
[IMG]https://4.top4top.net/s_1439pnwh31.jpg[/IMG]

very sensitive
I recommend making them, as the hand senses over 20 cm, the computer senses over 5 meters and many advantages

I shrunk the antenna so that the amplifier will not malfunction
By extending the antenna, it picks up the TV signal from 3 m

https://www.youtube.com/watch?v=kiaZ9xE0KEU

preamp high impedance
 

This circuit is very high impedance Preamp, this schema sharing one Friend from this forum.

You must use CA3130 (very high impedance), 741 operational has a very low input impedance.

ZAHORI WORK FINE WITH CA3130 :)

I added a 50hz notch filter :D

it's active antenna for sound card VLF reception , it's not an LRL

https://www.qsl.net/dl4yhf/speclab/vlf_rcvr.htm

Is it not suitable for detecting electromagnetic fields of metals?

Maybe with some modification, it will be able to detect a big treasure at some meters

No this is vlf filter
It can be used at the inputs of some other circuits

Can be so like ..... :razz:
This is part from all system .

Even better:




https://i59.servimg.com/u/f59/19/61/60/05/remote10.jpg

GOOD CIRCUIT WHAT'S VLF RECEIVER , CAN YOU SHARE THE VALUES ?

:) But here Laser wave is in wrong um (micrometer) .

It is about thermal IR (long wave infrared) laser, in this application ranging

from 6μm to 14 μm wavelength. This region is molecular vibration wavelength.



https://api.intechopen.com/media/cha...2/media/F3.png

Now is Okay ,Dear WM6

Hi friend's
I see a long range detector , use fm radio wave for detecting metal in depth , and builder saying can detect only old objects in depth .
Transmission using fm radio section , and receiver detecting maybe reflection or phase different and alarmed .
Is that possible ?
Any body have idea?

you mean some thing like Raven from treasureNow?

https://www.geotech1.com/cgi-bin/pag...aven/index.dat