MAGNOMETER TECH QUESTION

[daverave]

i know very little about magnometers...is there any way just one sensor could be used instead of two to reject earth's magnetic field ??? or maybe should i try hall effect sensor ??? i need some discrimination with my pulse machine as one of the local beaches is infested with iron.

[Dave J.]

What theoretically might be possible is different from having something that works. Do you carry a strong magnet with you?

[WM6]

Do you carry a strong magnet with you?

For sand beaches good Ferro-ID idea.

Curious how near strong magnetic field of such magnet can imply to MD coil functionality?

[Orbit]

It is very easy to do ,i'm using this coil pi .

[daverave]

It is very easy to do ,i'm using this coil pi .

Hi Orbit...So how do i implement this ??? can one magnometer sensor or hall effect be used...or do i need two to reject earth's magnetic field...i guess a sensor near to coil will be a comprimise...and detector would need to be switched off before using the sensor ???

[Orbit]

To required switch is ,which excludes tx and includes magnetometer if such sensor I used the coil devices !
And if you use a special magnetometer then does not have to be turned off tx just be set the part where the magnetic field coils least !
Very simply used lm 386 audio amplifier and coil ..

[daverave]

To required switch is ,which excludes tx and includes magnetometer if such sensor I used the coil devices !
And if you use a special magnetometer then does not have to be turned off tx just be set the part where the magnetic field coils least !
Very simply used lm 386 audio amplifier and coil ..

Hi Orbit....im not really sure about what you are saying...i have some speake magnometers which someone donated to me and i have some hall effect sensors...and i have the carl morland designed pcb which i bought many years ago and never built at that time....im just very vague with magnometers.

[Ferric Toes]

Hi Orbit....im not really sure about what you are saying...i have some speake magnometers which someone donated to me and i have some hall effect sensors...and i have the carl morland designed pcb which i bought many years ago and never built at that time....im just very vague with magnometers.

Hi Dave,
I have not had any real success using magnetometers for ferrous discrimination. They are fine for larger iron targets but not much good for small nails and other tiny items which are a nuisance with a PI detector.

There are a lot of pinpointer probes on the market and it would be very useful to have one that has Fe/non-Fe identification. That would save a lot of time chasing small bits of iron in a hole. Does such a device exist? Ideally it needs to have a range of a couple of inches on a coin or ring.

Eric.

[daverave]

Hi Dave,
I have not had any real success using magnetometers for ferrous discrimination. They are fine for larger iron targets but not much good for small nails and other tiny items which are a nuisance with a PI detector.

There are a lot of pinpointer probes on the market and it would be very useful to have one that has Fe/non-Fe identification. That would save a lot of time chasing small bits of iron in a hole. Does such a device exist? Ideally it needs to have a range of a couple of inches on a coin or ring.

Eric.

Hi Eric...your right its the small nails and wire which are the main problem...not sure if a ferrous probe exists ??? ive noticed some detectors that incorperate a magnometer in the coil...like one called a black hawk and detec have a pulse detector with magnometer sensor in coil but i wonder if they work in any way or just a gimick????