Transmit Power?

[Duncan]

Aplologies if this question has been asked and answered in the past, but I was wondering if the amount of AC power fed to the transmit coil of an IB detector has any bearing on depth penetration?
Am I right in thinking that a higher (than normal) level of AC power fed to the coil would generate a more intense electromagnetic field that would penetrate further into the ground?

Duncan

[Max]

Aplologies if this question has been asked and answered in the past, but I was wondering if the amount of AC power fed to the transmit coil of an IB detector has any bearing on depth penetration?
Am I right in thinking that a higher (than normal) level of AC power fed to the coil would generate a more intense electromagnetic field that would penetrate further into the ground?

Duncan

Hi,
yes, you are right BUT more power would mean easy saturation could be reached, also on normal ground, due the fact that more coupling between tx and rx don't mean always a better S/N (signal to noise ratio).
What's really important in such devices is always S/N... cause if you have double the tx power but multiplied e.g. x4 noise... you just lose performance!
That happen easy... on the real field, of course you could made a powerful md that see a coin at 70cm in the air... but ,then, don't try to use it on the field ! Or you would detect the UFOs too...

That's why some really small power tx detectors (e.g. tesoro's) could beat any other "powerful" vlf... they rocks cause have a very good S/N!

Best regards,
Max

[Carl-NC]

A good analogy for metal detectors, is shining a light in the fog. A more powerful light will not penetrate any further, but will cause a lot more glare.

- Carl

[Geo]

You have right but I will place the subject little otherwise. The big power as all you say creates reflections in rock ground and in heavy ground . What becomes however in soil without rocks, as they is the fields and the beaches? My experience showed me that there the big power gives bigger depth. Whenever rather a switch to choice the power would be the better choice provided that in the parts that we search they have soft grounds

[Max]

You have right but I will place the subject little otherwise. The big power as all you say creates reflections in rock ground and in heavy ground . What becomes however in soil without rocks, as they is the fields and the beaches? My experience showed me that there the big power gives bigger depth. Whenever rather a switch to choice the power would be the better choice provided that in the parts that we search they have soft grounds

Hi Geo,
I agree... but depends on sand composition too...
If you have too iron oxides in sand... a powerful tx on a VLF make you see the UFOs too there!

Fact is that if you have a good soil and flat uniform conditions (like in air tests) you could gain depth... you'll not degrade your S/N much in flat uniform conditions... no hot-rocks, no black-sand, not too oxides

but problem is that there are too few places like this!

A general purpose detector must, then, be low powered...
to avoid much troubles...

Another example is on PI... I've tested GS4... wow on the beach what a machine! Powerful, great depth ! But then I switched to inland... and found tons of pottery, bricks ... and then hang it on the wall.

Best regards,
Max