Elektor 5/07 Magnetometer

[teknoloji]

Andy Flind's project on EPE (January 1995) is based also on transformer. Signal shows via 10 leds and audio variation. Uses common chips. You can modificate it for various purposes.

Hello
Pictures can not be read. install a large clean image.
If you install it, or epe magazine 1995 issue.

Thank you.

[okantex]

Hi İKUMİ5
did you completed this magnetometer.

is it suitaable for metal and cavity search.

did you try it with polar anttenas

best regards
okantex

[ikumi5]

Simple Magnetometer project found at follow link:
http://www.elektor-electronics.co.uk...rt=53325&PN=On
Using 220V/12V mains transformer for sensor.

Hi Rael,

PCB that i made from your schematic diagram.

many thanks!!!

regards

ikumi5

Simple Magnetometer project found at follow link:
http://www.elektor-electronics.co.uk...rt=53325&PN=On
Using 220V/12V mains transformer for sensor.

good day!!!

Sir,I think your circuit is easy to build, please can you post a much greater resolution of your schematic diagram or please sent me your schematic diagram at [email protected]

[okantex]

there adc is used to get digital output to pc to get visual results.nothing else.may be helpfull to differ metal and cavity.

[Crowbar]

At EMFAD datasheet is mentioned that is detects conductive materials and such anomalies using stand alone VLF radio stations- so it's interesting what is SNR and sensitivity of a coil systems in it if whole system serachs at max depth of 12m and has 10bit ADC with 5V dynamic range.

I mean how it can detect any physical object at normal range without any trasmitter-reciever techniques...

Maybe misunderstand you, BUT, have you tried opening your eyes? you should then be able to detect/see physical object at normal range, and maybe you no trip over and face first in mud.

[okantex]

can not it be changed to 10khz -150khz range.may be 10-40khz, 40-80khz,80-120khz,120-150khz.selectable frequency ranges.
if we can do it.it will work like emfad.

[rael]

The ELF receiver use 1-23 Hz frequency range /Elektor 5/2007/. More about this project found at follow link:
http://www.vlf.it/kurt_2/ELF-Signals.htm

Мany VLF, ELF receivers are designed for receiving signals from power terrestrial transmitter, emitting VLF-ELF waves.
http://www.vlf.it/itulist/itulist.htm
http://www.vlf.it/

[Crowbar]

I mean how it can detect any physical object at normal range without any trasmitter-reciever techniques...

[Crowbar]

It's very strange how does an EMFAD searchs in VLF range 44KHz and up without any active transmitter.

[okantex]

what about the ELF(150kz) reciever project at same magazin?
did any body try it.it looks like EMFAD UG12 in manner.
can not it be used as it if antenna hold like detector ,I mean directly to ground.

[rael]

Hi,

More about magnetometers and gradiometers You can find at Geotech's Magnetometer Projects and Magnetometer References pages.

http://geotech.thunting.com/cgi-bin/...sors/index.dat
http://geotech.thunting.com/cgi-bin/...fmx1/index.dat

"Gradiometers.
One of the problems with magnetometers is that small fluctuations occur in otherwise very large magnetic fields,
and those fluctuations can sometimes be important. A further problem with singlesensor systems is that they are very
sensitive to orientation. Even a small amount of rotation can cause unacceptably large, but spurious, output changes.
The changes are real, but are not the fluctuations that you are seeking. A gradiometer is a magnetic instrument
that uses two identical sensors that are aligned with each other so as to produce a zero output in the presence of a
uniform magnetic field. If one of the sensors comes into contact with some sort of small magnetic anomaly, then it
will upset the balance between sensors, producing an output. The gradiometer gets its name from the fact that it measures
the gradient of the magnetic field over a small distance (typically 1 to 5 feet)."

"Expermenting With Magnetic Sensors" by Joseph J. Carr, part 2 page 3

I think, transformmer sensor have insufficient sensitivity for field research use.

On the subject of Gradiometers, exactly what are they good at doing? Is there some info on them somewhere to read?

[Crowbar]

Gradiometer and induction magnetometer are different things.