Detecting in wet sand?

GeauxLSU

Jr. Member
Apr 2, 2013
30
9
Baton Rouge, La
Primary Interest:
All Treasure Hunting
Upvote 0

streetglide

Jr. Member
Aug 17, 2011
82
44
Santa Barbara ca.
Detector(s) used
Mxt, Excal. 800, 1000
Primary Interest:
Beach & Shallow Water Hunting
Try the wet sand with your MXT. If the machine is not stable move up to the dry sand, that will tell you what area of wet sand the machine will be stabile at.My MXT is not stable at all in the wet sand,to solve that problem I bought a Excal. Good luck Joe.
 

baywalker

Bronze Member
Aug 24, 2011
1,116
432
Southwest Florida
Detector(s) used
Garrett & Fisher
Minelab Excaliber II
Garrett Pro Pointer
Primary Interest:
All Treasure Hunting
Wet sand is wet sand whether it is in your back yard or at the beach and it does give you more depth .
 

coryg

Jr. Member
Mar 18, 2013
92
58
Upstate, NY
Detector(s) used
Garrett AT Pro
Primary Interest:
All Treasure Hunting
The ace 350 bugs out on the beach close to the water. I don't know what it is, but the machine does not like wet sand and salt water.
 

Terry Soloman

Gold Member
May 28, 2010
19,423
30,109
White Plains, New York
🥇 Banner finds
1
🏆 Honorable Mentions:
1
Detector(s) used
Nokta Makro Legend// Pulsedive// Minelab GPZ 7000// Vanquish 540// Minelab Pro Find 35// Dune Kraken Sandscoop// Grave Digger Tools Tombstone shovel & Sidekick digger// Bunk's Hermit Pick
Primary Interest:
Metal Detecting
Wet sand is wet sand whether it is in your back yard or at the beach and it does give you more depth .

Sorry, but this is NOT correct. Are you detecting in the saltwater and on wet ocean sand, or will you be hunting dry sand and freshwater lakes and river beaches? This is important because there are different metal detectors designed for fresh- or, salt- water use. For instance, a "VLF" or very low frequency type metal detector works extremely well on dry sand and in fresh water. It does not work as well in saltwater, or on wet ocean-water beaches. In highly conductive saltwater conditions pulse induction or "PI," and multi-frequency VLF "BBS" metal detectors excel.

The VLF metal detector sends 4,000 - 80,000 radio (sign) waves per-second into the ground. When the radio waves hit something conductive - like an iron nail, gold ring, coin or aluminum pull-tab, a magnetic field sets up around the object and a particular signal frequency is transmitted back to the detector's receiving coil. VLF metal detectors have the ability to "discriminate," or tell what type of metal they are seeing by "reading" the return signal frequency.

An iron nail for example, has a different frequency than a silver coin. The processor in the metal detector knows the difference between the two, and can be set to remain silent when seeing the nail. However, the radio waves bounce off everything that is conductive in the sand or water. This is why VLF detectors must be "ground balanced" to work effectively in highly mineralized soil, or on highly conductive saltwater beaches. You must tune or adjust the machine to see through the "fog," or white-noise created by the salt and iron in the sand or water you are detecting. Unfortunately, this usually leads to a loss of depth and stability with most VLF detectors.

Minelab has a fully submersible VLF beach machine that can discriminate out iron in wet sand and saltwater. The “Excalibur” uses Broad Band Spectrum, or “BBS” technology, and retails for about $1,300.00. According to Minelab, their BBS operating system, “simultaneously transmits, receives and analyses a broad band of multiple frequencies to deliver substantial detection depth, high sensitivity and accurate discrimination for a wide range of target types.” The key takeaway here is “multiple frequencies.” Unfortunately, radio waves regardless of their frequency still have to be filtered and balanced in heavily conductive wet-ocean sand and highly mineralized saltwater. That limits the systems depth capabilities.

The magnetic iron sands (“Black Sands”), salt, and high concentrations of other minerals in the water and sand conspire to bounce the radio waves away from the target. Conductivity and mineralization act like a shield around the target and create white noise that must be filtered electronically. Think of it as turning on your bright headlights in a heavy fog at night. All that powerful light is diffused and causes a complete white out – you can’t see anything three-feet past the hood of your car! However when you turn on your yellow fog lights, you can see a little further – not as far as you could in clear daylight, but further. That is why all radio wave machines must be “ground balanced” or tuned, to maximize their depth potential, and why BBS filters and multi-frequencies are so effective – yet still limited.

Unlike BBS and VLF metal detectors which constantly send and receive thousands of low frequency radio waves per second, a Pulse Induction (PI) metal detector fires high-voltage pulses into the sand several hundred times per second. If no metal is present the electric pulse decays at a uniform rate with no anomalies. When metal is present a small “eddy” current flows through it causing the voltage decay time to increase, which creates a measurable anomaly. Unlike VLF radio waves, electronic pulses are impervious to the effects of conductivity and mineralization, and are unaffected by salt or black sands.

Using the same heavy fog at night metaphor that I referred to earlier, pulse induction is like headlights that cut completely through the fog as if it were not there at all. The trade-off for that added depth and clarity is the inability to discriminate, or block out iron targets that you generally don’t want to waste time and energy digging. While a pulse induction machine detects all metals without discrimination, the minute differences in the signal tone and quality can give a skilled and experienced operator a clue as to what the target may, or may not be.
 

OP
OP
GeauxLSU

GeauxLSU

Jr. Member
Apr 2, 2013
30
9
Baton Rouge, La
Primary Interest:
All Treasure Hunting
Sorry, but this is NOT correct. Are you detecting in the saltwater and on wet ocean sand, or will you be hunting dry sand and freshwater lakes and river beaches? This is important because there are different metal detectors designed for fresh- or, salt- water use. For instance, a "VLF" or very low frequency type metal detector works extremely well on dry sand and in fresh water. It does not work as well in saltwater, or on wet ocean-water beaches. In highly conductive saltwater conditions pulse induction or "PI," and multi-frequency VLF "BBS" metal detectors excel.

The VLF metal detector sends 4,000 - 80,000 radio (sign) waves per-second into the ground. When the radio waves hit something conductive - like an iron nail, gold ring, coin or aluminum pull-tab, a magnetic field sets up around the object and a particular signal frequency is transmitted back to the detector's receiving coil. VLF metal detectors have the ability to "discriminate," or tell what type of metal they are seeing by "reading" the return signal frequency.

An iron nail for example, has a different frequency than a silver coin. The processor in the metal detector knows the difference between the two, and can be set to remain silent when seeing the nail. However, the radio waves bounce off everything that is conductive in the sand or water. This is why VLF detectors must be "ground balanced" to work effectively in highly mineralized soil, or on highly conductive saltwater beaches. You must tune or adjust the machine to see through the "fog," or white-noise created by the salt and iron in the sand or water you are detecting. Unfortunately, this usually leads to a loss of depth and stability with most VLF detectors.

Minelab has a fully submersible VLF beach machine that can discriminate out iron in wet sand and saltwater. The “Excalibur” uses Broad Band Spectrum, or “BBS” technology, and retails for about $1,300.00. According to Minelab, their BBS operating system, “simultaneously transmits, receives and analyses a broad band of multiple frequencies to deliver substantial detection depth, high sensitivity and accurate discrimination for a wide range of target types.” The key takeaway here is “multiple frequencies.” Unfortunately, radio waves regardless of their frequency still have to be filtered and balanced in heavily conductive wet-ocean sand and highly mineralized saltwater. That limits the systems depth capabilities.

The magnetic iron sands (“Black Sands”), salt, and high concentrations of other minerals in the water and sand conspire to bounce the radio waves away from the target. Conductivity and mineralization act like a shield around the target and create white noise that must be filtered electronically. Think of it as turning on your bright headlights in a heavy fog at night. All that powerful light is diffused and causes a complete white out – you can’t see anything three-feet past the hood of your car! However when you turn on your yellow fog lights, you can see a little further – not as far as you could in clear daylight, but further. That is why all radio wave machines must be “ground balanced” or tuned, to maximize their depth potential, and why BBS filters and multi-frequencies are so effective – yet still limited.

Unlike BBS and VLF metal detectors which constantly send and receive thousands of low frequency radio waves per second, a Pulse Induction (PI) metal detector fires high-voltage pulses into the sand several hundred times per second. If no metal is present the electric pulse decays at a uniform rate with no anomalies. When metal is present a small “eddy” current flows through it causing the voltage decay time to increase, which creates a measurable anomaly. Unlike VLF radio waves, electronic pulses are impervious to the effects of conductivity and mineralization, and are unaffected by salt or black sands.

Using the same heavy fog at night metaphor that I referred to earlier, pulse induction is like headlights that cut completely through the fog as if it were not there at all. The trade-off for that added depth and clarity is the inability to discriminate, or block out iron targets that you generally don’t want to waste time and energy digging. While a pulse induction machine detects all metals without discrimination, the minute differences in the signal tone and quality can give a skilled and experienced operator a clue as to what the target may, or may not be.


Wow, thanks for all the information!!! That definitely helps me understand the subject better. Thanks again!! :headbang:
 

Sir Gala Clad

Bronze Member
Jul 9, 2012
1,330
511
🏆 Honorable Mentions:
1
Primary Interest:
All Treasure Hunting
Baywalker: It depends on what metal detector you are using.
 

califteacher

Full Member
Sep 30, 2012
162
232
Vista, San Diego County, CA
Detector(s) used
Minelab CTX3030 and Excalibur II
Primary Interest:
Beach & Shallow Water Hunting
Thank you for taking the time to write such an detailed reply. It is nice to see a thread that is so informative and educational, which is what this site should be about.
 

baywalker

Bronze Member
Aug 24, 2011
1,116
432
Southwest Florida
Detector(s) used
Garrett & Fisher
Minelab Excaliber II
Garrett Pro Pointer
Primary Interest:
All Treasure Hunting
Terry I wish I could be as articulate as you ,I was just speaking in general terms and using dif detectors in each location. We had just had a good rain down here and it got the normally dry beach sand wet down to 10"and I have found that it gives me better signal ?
 

Top Member Reactions

Users who are viewing this thread

Top