What similarity ?, what differences ?

[aft_72005]

Hi ,
My question from LRL mans
What similarity and what differences is between metal detector
And LRL or pistol detector ?
Best regards.

[aft_72005]

Originally Posted by aft_72005

Hi ,
My question from LRL mans
What similarity and what differences is between metal detector
And LRL or pistol detector ?
Best regards.

Without reply !!!!!!????

[J_Player]

Originally Posted by aft_72005

Without reply !!!!!!????

Maybe LRL experts do not know what the differences are. ?

From the perspective of a person who understands metal detector theory and LRL theories, I can explain what appears to be the diffrerence in theories and maybe operation between LRLs and metal detectors. Maybe an LRL expert who knows the answers can find some errors in my perspective and explain how it really works.

To begin, there are many kinds of LRLs:
A. Dowsing and electronically enhanced dowsing types.
B. Active coil types that broadcast an alternating signal that may be detected by any number of means.
C. Passive electronic types that listen for signals similar to a radio receiver with no transmitter.
D. Hybrid types that use a modified metal detector of some sort combined with "strange" circuitry that is not well explained.

There are many variations of these kinds of LRLs with overlapping between the classifications.
Variations can include using any of the following TX and RX methods:
1. Coils tuned to ELF, VLF and any other RF frequency into the microwave region (most often VLF).
2. Ariel antennas operating at anywhere between ELF to microwave.
3. LEDs, Lasers for TX of a beam to stimulate different areas of ground to be scanned, and coils to detect the response from the ground.
4. Broadcast band receivers used in passive mode or in conjunction with low power transmitters.
5. Electrostatic electronic sensors.
6. Dowsing rods with electronics added, such as low power signal generators connected to the rods or to the ground, or broadcasting in the air.
7. Dowsing rods with samples, magnets or "power loads" added to somehow influence the effectiveness of the rods.

Of all the kinds of LRLs I listed, the most similar to a metal detector is the TX/RX coil style pistol detector.
What is different?

Metal detector theory
Metal detector theory requires the TX coil to produce eddy currents in a target metal that can be detected in a receiver circuit. This depends on using a sensitive circuit and coil that can pick up the eddy currents, and hopefully examine the kind of eddy current to help determine what kind of metal is detected. Metal detectors are limited by the range of the magnetic field that can be transmitted as well as the range of the magnetic field of eddy currents. When the RX circuits are turned up to a high enough gain for maximum range, the problem becomes electronic noise from the internal circuits. If the circuits are optimized for minimal noise, then the second problem of external noise will become prominent --- noise from power lines, EMI, RF in the air, and even noises from the ground due to variations in earth currents interacting with mineralization in the soil. In order to avoid this kind of interference, most detectors have a faraday shield and ground balance circuits to "de-sensitize" the electronics so it will find signals that are not buried in the noise. The remaining signal is focused on the magnetic field with the electric field removed.

PD theory
If we compare a simple TX/RX coil type PD LRL to a metal detector, the first difference is there is no Faraday shield. The PD is also equipped with adjustments that allow it to be tuned much deeper into the noise region, and in some cases beyond stable circuit operation. We hear the experts of LRLs tell how it is necessary to move very slowly and hold the PD steady out in front pointed below the horizon, as well as not to wear clothing that collects static. It would seem they are trying to detect a signal at the extreme sensitivity adjustment, where any user movements could cause false signals. In fact, I expect this sort of detection to pick up a lot of EMI/RF and other interference noise from the air. The signals they are looking to find are not eddy current signals. For a VLF coil to receive a signal more than a meter or so, it must be operating as a radio receiver looking for variations in the broadcast signal. Without a Faraday shield, the electric field is not inhibited, so full RF TX and RX are possible. Possibly the amount of RF that is absorbed in the soil changes, and the diffraction of RF can be sensed. Or maybe there are RF reflections when a target is in range. According to some of the LRL experimenters, there is a hot spot in the location of long time buried metals that interacts with the signal they receive. It is unclear whether this signal must be transmitted, or if it exists separately from a transmitter, and can be detected with a simple passive receiver.


So far I described the theoretical difference between only one kind of LRL and a metal detector. There are many other kinds of LRLs.

The common difference LRLs all have from a metal detector can be summarized as follows:
1. They are claimed to detect metals at long distance using methods that cannot be demonstrated to be working live in front of skeptical witnesses.
2. Most LRLs require long-time buried metals in order to work. LRL experts claim they detect a secondary phenomenon that develops after metal has been buried a long time. But what secondary phenomenon they claim to detect has never been explained in a manner that can be demonstrated or duplicated. Usually the method of operation claimed can be shown to be untrue with simple instruments.
3. Anyone with electronics and construction skills can build a metal detector that works. Nobody can build an LRL that works except a very few people who do not demonstrate the LRL working in front of skeptical witnesses*. The idea that their LRL works exists only in their stories, not in the experience of most people who read their stories.
4. All LRLs seem to require special methods or skills to use them successfully. From dowsing to electronic coil LRLs, there are special instructions that must be followed before any chance of detecting can happen. Also the "environmental conditions" must be favourable in order for them to work. These requirements seem to work to compliment the fact that LRLs cannot be demonstrated in front of skeptical witnesses. These requirements also work to compliment the fact that nobody can build an LRL except the very few people who say they can, but do not demonstrate them working.

Those are some differences between metal detectors and LRLs that I have observed from a technical perspective.
Are there any LRL builders or users that see some errors in my observations, or know some more differences?

Best wishes,
J_P

* Exception: Morgan and Geo demonstrated LRLs they built to other forum member (not completely skeptical). Maybe there are a few others who also did?

[Gwil]

(1) Metal detectors operate on well established scientific principles.

(2) LRLs apparently operate on theories that do not appear in any textbook and that would be worth several Nobel prizes if they could be proved correct.

Perhaps one day those Nobel prizes will be awarded. But I have my doubts.

Gwil

[J_Player]

Originally Posted by Gwil

(1) Metal detectors operate on well established scientific principles.

(2) LRLs apparently operate on theories that do not appear in any textbook and that would be worth several Nobel prizes if they could be proved correct.

Perhaps one day those Nobel prizes will be awarded. But I have my doubts.

Gwil

I agree,
Nobel Prizes are awarded to people who demonstrate they have made a great accomplishment.
If it is not demonstrated to be correct to the Nobel Prize committee, then there will be no prize.

Best wishes,
J_P

[detectoman]

hello aft, the lrl difference is; these lrl are put in reception limits, are dm extremely hot"
but whit special support
md have little radio of magnetic irradiation
lrl extended these radio of propagation and reception in waves multiples' armonic
i see, esteban can give you exact detail
i never tried my probable wrongs stuff lrls
im entusiast hobbyst
i am teoric builder, but when i sure any lrl of me is experiment superior, and my buried coins already, i go try all these extrange cacharros

[aft_72005]

Originally Posted by J_Player

Maybe LRL experts do not know what the differences are. ?

From the perspective of a person who understands metal detector theory and LRL theories, I can explain what appears to be the diffrerence in theories and maybe operation between LRLs and metal detectors. Maybe an LRL expert who knows the answers can find some errors in my perspective and explain how it really works.

To begin, there are many kinds of LRLs:
A. Dowsing and electronically enhanced dowsing types.
B. Active coil types that broadcast an alternating signal that may be detected by any number of means.
C. Passive electronic types that listen for signals similar to a radio receiver with no transmitter.
D. Hybrid types that use a modified metal detector of some sort combined with "strange" circuitry that is not well explained.

There are many variations of these kinds of LRLs with overlapping between the classifications.
Variations can include using any of the following TX and RX methods:
1. Coils tuned to ELF, VLF and any other RF frequency into the microwave region (most often VLF).
2. Ariel antennas operating at anywhere between ELF to microwave.
3. LEDs, Lasers for TX of a beam to stimulate different areas of ground to be scanned, and coils to detect the response from the ground.
4. Broadcast band receivers used in passive mode or in conjunction with low power transmitters.
5. Electrostatic electronic sensors.
6. Dowsing rods with electronics added, such as low power signal generators connected to the rods or to the ground, or broadcasting in the air.
7. Dowsing rods with samples, magnets or "power loads" added to somehow influence the effectiveness of the rods.

Of all the kinds of LRLs I listed, the most similar to a metal detector is the TX/RX coil style pistol detector.
What is different?

Metal detector theory
Metal detector theory requires the TX coil to produce eddy currents in a target metal that can be detected in a receiver circuit. This depends on using a sensitive circuit and coil that can pick up the eddy currents, and hopefully examine the kind of eddy current to help determine what kind of metal is detected. Metal detectors are limited by the range of the magnetic field that can be transmitted as well as the range of the magnetic field of eddy currents. When the RX circuits are turned up to a high enough gain for maximum range, the problem becomes electronic noise from the internal circuits. If the circuits are optimized for minimal noise, then the second problem of external noise will become prominent --- noise from power lines, EMI, RF in the air, and even noises from the ground due to variations in earth currents interacting with mineralization in the soil. In order to avoid this kind of interference, most detectors have a faraday shield and ground balance circuits to "de-sensitize" the electronics so it will find signals that are not buried in the noise. The remaining signal is focused on the magnetic field with the electric field removed.

PD theory
If we compare a simple TX/RX coil type PD LRL to a metal detector, the first difference is there is no Faraday shield. The PD is also equipped with adjustments that allow it to be tuned much deeper into the noise region, and in some cases beyond stable circuit operation. We hear the experts of LRLs tell how it is necessary to move very slowly and hold the PD steady out in front pointed below the horizon, as well as not to wear clothing that collects static. It would seem they are trying to detect a signal at the extreme sensitivity adjustment, where any user movements could cause false signals. In fact, I expect this sort of detection to pick up a lot of EMI/RF and other interference noise from the air. The signals they are looking to find are not eddy current signals. For a VLF coil to receive a signal more than a meter or so, it must be operating as a radio receiver looking for variations in the broadcast signal. Without a Faraday shield, the electric field is not inhibited, so full RF TX and RX are possible. Possibly the amount of RF that is absorbed in the soil changes, and the diffraction of RF can be sensed. Or maybe there are RF reflections when a target is in range. According to some of the LRL experimenters, there is a hot spot in the location of long time buried metals that interacts with the signal they receive. It is unclear whether this signal must be transmitted, or if it exists separately from a transmitter, and can be detected with a simple passive receiver.


So far I described the theoretical difference between only one kind of LRL and a metal detector. There are many other kinds of LRLs.

The common difference LRLs all have from a metal detector can be summarized as follows:
1. They are claimed to detect metals at long distance using methods that cannot be demonstrated to be working live in front of skeptical witnesses.
2. Most LRLs require long-time buried metals in order to work. LRL experts claim they detect a secondary phenomenon that develops after metal has been buried a long time. But what secondary phenomenon they claim to detect has never been explained in a manner that can be demonstrated or duplicated. Usually the method of operation claimed can be shown to be untrue with simple instruments.
3. Anyone with electronics and construction skills can build a metal detector that works. Nobody can build an LRL that works except a very few people who do not demonstrate the LRL working in front of skeptical witnesses*. The idea that their LRL works exists only in their stories, not in the experience of most people who read their stories.
4. All LRLs seem to require special methods or skills to use them successfully. From dowsing to electronic coil LRLs, there are special instructions that must be followed before any chance of detecting can happen. Also the "environmental conditions" must be favourable in order for them to work. These requirements seem to work to compliment the fact that LRLs cannot be demonstrated in front of skeptical witnesses. These requirements also work to compliment the fact that nobody can build an LRL except the very few people who say they can, but do not demonstrate them working.

Those are some differences between metal detectors and LRLs that I have observed from a technical perspective.
Are there any LRL builders or users that see some errors in my observations, or know some more differences?

Best wishes,
J_P

* Exception: Morgan and Geo demonstrated LRLs they built to other forum member (not completely skeptical). Maybe there are a few others who also did?

Hi J_ Player, hi all
Thanks for your exactly point of view. It was usefully. But my question from you and other
Members about " absorption with stimulator transmitter " now .

How it work ? I need data for designing …….
Best regards.

[detectoman]

morgan, i think you can eliminate aluminium detection, whit modification on coil form, & wire's specification, or anten frecuences etc
each tipe of lrl is whit distinct capabilites and distinct troubles

[J_Player]

Originally Posted by aft_72005

Hi J_ Player, hi all
Thanks for your exactly point of view. It was usefully. But my question from you and other
Members about " absorption with stimulator transmitter " now .

How it work ? I need data for designing …….
Best regards.

Nobody has ever given information about absorption with a stimulator transmitter. For long range metal detecting, the term absorption is meaningless outside the context of light, in which light frequencies can be absorbed by various materials. Another possibility is in reference to RF which can be absorbed by materials depending on the frequency of the RF and the composition of the materials that are absorbing the RF.

According to Esteban, there are emissions from the ground of long time buried metals which he depicted as a sine wave in his diagram above titled "phenomenon from gold signal".
Does this mean that long time buried metals emit a sine wave?

I don't think so.
What does it mean?

-- Nothing that can be measured or demonstrated with any standard instruments. The only instrument that is claimed to absorb these alledged emissions from buried metals is an LRL.
The design and construction details are shown in Esteban's post above so you can build an emission sensor to detect the "phenomenon from gold signal" for yourself and decide if there are any emissions from long time buried metals.

However, the diagrams from Esteban do not show how to build an absorption with stimulator transmitter. It is simply a passive receiver. The basic design of the passive receiver is the same as a simple radio receiver with an amplifier. The important details are in the construction, which apparently is designed to optimize the signal received to select a very specific artifact from the noise being tuned.

If you wanted to build a version that has a stimulator transmitter, then you may need to use a different design than the one shown. Vernell Electronics sells the kind you are asking about which consist of a 555 signal generator to send a signal into a field, while holding a small hand-held coil receiver that tunes RF as you walk through the field. Theoretically, you should find a signal line running from the target metal to the transmitter where you will find altered reception of the TX signal from your coil.

The 555 signal generator has a selector switch that will chose various frequencies used to find different metals. It the early models such as the VR-800, the 555 circuit has no power amp, and simply sends the 555 output to be broadcast.

Here is a photo of another similar kind of LRL that uses a stimulator transmitter and coil receiver:

[FrancoItaly]

Hi All
I think that, as Esteaban says, the phenomenon it has many aspects and with a passive receiver we will have many difficulties in order to select the just signal. The better thing it's to use a transmitter/receiver system and to look for little changes in received signal. Obviously some frequencies are better than others and it's necessary to maximize the "antenna arrangement" in order to pick up and to converter the "lrl signal". I'm working about a ferrite arrangement, TR-IB Balance, for the moment only in my laboratory.

Best Regards

[Esteban]

Originally Posted by J_Player

Nobody has ever given information about absorption with a stimulator transmitter. For long range metal detecting, the term absorption is meaningless outside the context of light, in which light frequencies can be absorbed by various materials. Another possibility is in reference to RF which can be absorbed by materials depending on the frequency of the RF and the composition of the materials that are absorbing the RF.

According to Esteban, there are emissions from the ground of long time buried metals which he depicted as a sine wave in his diagram above titled "phenomenon from gold signal".
Does this mean that long time buried metals emit a sine wave?

I don't think so.
What does it mean?

-- Nothing that can be measured or demonstrated with any standard instruments. The only instrument that is claimed to absorb these alledged emissions from buried metals is an LRL.
The design and construction details are shown in Esteban's post above so you can build an emission sensor to detect the "phenomenon from gold signal" for yourself and decide if there are any emissions from long time buried metals.

However, the diagrams from Esteban do not show how to build an absorption with stimulator transmitter. It is simply a passive receiver. The basic design of the passive receiver is the same as a simple radio receiver with an amplifier. The important details are in the construction, which apparently is designed to optimize the signal received to select a very specific artifact from the noise being tuned.

If you wanted to build a version that has a stimulator transmitter, then you may need to use a different design than the one shown. Vernell Electronics sells the kind you are asking about which consist of a 555 signal generator to send a signal into a field, while holding a small hand-held coil receiver that tunes RF as you walk through the field. Theoretically, you should find a signal line running from the target metal to the transmitter where you will find altered reception of the TX signal from your coil.

The 555 signal generator has a selector switch that will chose various frequencies used to find different metals. It the early models such as the VR-800, the 555 circuit has no power amp, and simply sends the 555 output to be broadcast.

Here is a photo of another similar kind of LRL that uses a stimulator transmitter and coil receiver:

You're right. The sine wave is only indicative.

Esteban