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msysta
02-12-2010, 12:38 PM
Hello,

When soil is frozen weird ideas come to you:

Would it be possible to do such setup for metal detecting where transmitter would be separated as standalone box in middle of the search area? Transmitting happening via underground "antenna" like steel rod or similar. Like take 6 feet rod and hammer it into the soil, connect tx output to it and power up.

This would be interesting because it could use "enourmous" tx power (by aggregate or other ext power source) compared to handheld devices.

The concern would be the rx side. Would normal detector with ground balance and without own tx circuit work with this? How far would it reach?

Are there any such tryouts?

thanks,
Markus

J_Player
02-12-2010, 01:28 PM
Hello,

When soil is frozen weird ideas come to you:

Would it be possible to do such setup for metal detecting where transmitter would be separated as standalone box in middle of the search area? Transmitting happening via underground "antenna" like steel rod or similar. Like take 6 feet rod and hammer it into the soil, connect tx output to it and power up.

This would be interesting because it could use "enourmous" tx power (by aggregate or other ext power source) compared to handheld devices.

The concern would be the rx side. Would normal detector with ground balance and without own tx circuit work with this? How far would it reach?

Are there any such tryouts?

thanks,
MarkusThis is a method used by geologists to locate a lot of things under the ground. There are several kinds of signals they use, from ground resistivity, induced polarization, and a few other techniques when driving rods into the ground. There are also VLF surveys, where geologists use the signal from existing government maintained VLF transmitters that are constantly running to produce signals under the ground. These transmitters allow you to survey an area by simply carrying a VLF receiver loop around and looking for variations. You can read a lot about these methods in the Geophysics forum above.

The only problem with these methods is they are not normally used for hobby metal detecting, but to map larger ore bodies, and rock formations or faults. I have heard people talk about ideas to use these methods for ordinary metal detecting or for cache locating. Maybe they can be used as you described.

Best wishes,
J_P