New detecting method?

[J_Player]

Originally Posted by g-sani

Hi J_P
Once many years back a friend of mine gave me a gold gun al718 for a month to see if it can detect anything or not.
There was a single page inside its box roughly explaining its operation.
All I paid attention then it was a part saying that if the pistol like detector was pointed to a precious burried target goes silent.
I discovered some guns from the 2nd world war once from about 50 meters and some other time it was 5 or 6 bullets spread close to each other but only 15cm deep.I was surprised to see that it was easy to go on target.
The gold gun has a digital voltmeter giving different readings as you sweep it from side to side apart from the amplified audio signal in the speaker.
I didn't use it many times to say the truth but I could tell whith the experience I had those days that this pistol could detect something.
This is how and why I got my goldgun later on from a shop that was closing down in States.I bought it for much less money than what Accurate Locators used to sell it.
I discovered later on that probably this type of lrl doesn't work any more since most of the VLF stations arround Greece closed down.
Some other users here in Greece say that there are some emmisions in certain days but thats not a solution for me.
Even accurate locators made a Tx later and started selling it again until it was for some reason discontinued.
So I am in position now looking for a Tx to duplicate the emf fields of the old days that don't exist now.
But the truth is I always leave it behind J_P because I can not reach to a right conclusion of what is best to do.

I can put photos down of the cct or the pistol itself but I think somebody put some already in the forum under some other thread.

Hi g-sani,
The way you describe the performance of the gold gun sounds similar to a radio direction finder. It sounds like it works by tuning the VLF signal from a distant transmitter that is no longer transmitting. How it can detect buried guns, I don't know. But if it needs a VLF signal to work, then this would explain why there were VLF transmitters manufactured to make a new VLF transmission after the VLF transmitter was shut down.

From what you posted, I would think you first need to determine what frequency the gold gun is tuned to (I think I remember it is somewhere around 60KHz). You may be able to send an email to the company that sold the transmitters, and ask what frequency they are. Then you could build a transmitter that sends a VLF signal at this frequency to put near your treasure hunting area. I think WM6 can give some good information on how to do this.

Best wishes,
J_P

[Qiaozhi]

The Gold Gun has 3 ranges:

1. 9.5KHz for long distance and weak EM fields.
2. 26.7-27KHz for USA.
3. 19.2KHz England, Philippines, Greece and USSR.

Or so they claim.

[WM6]

Originally Posted by J_Player

If you were use a small transmitter at your hunting site, then the signal coming from this transmitter will be broadcasting RF in the near field, whose propagation properties are not the same as transmitters far in the distance.

Yes, but huge changing in propagation (like changing wave polarization etc) are in first line characteristic of very high frequency band as UHF not in VLF/ULF band. By local small transmitter we find some others aspect of problem. We are searching for weak source of reflected signal and at the same time we have in vicinity relative strong source of transmitted signal at the same frequency which cover weak target signal and disturb successive search . This is why I repeated that 0.3W is far enough and even too much for successive search. This is why we need as much as possible directive RX antenna to suppress direct TX signal in combination with some tricks and searching skill.

If we compare UHF and ULF frequency band from reflectivity view UHF are better to detect especially small target in air because of its directivity and worse to detect something underground because of his weak penetration ability, on other side ULF are weak on directivity and so worse to detect something in air but way better to detect something underground because of his excellent penetration ability in soil. Theoretically ULF radar can detect invisible objects (objects behind of hills or behinds of horizon) which UHF radar cannot. This is why ULF can reach targets on unusual way and why we speak about importance of RX sensitivity and Rx antenna directivity.

[g-sani]

Originally Posted by WM6

I don't know what of instruments do you have in your lab.

If you start from "Gold gun" which is real for you, you need first to measure all of (as you say) three frequencies of your AL707. Do not believe to producers data it may vary, but because of ferrite antenna ("widest" Q) real data can be inside of acceptable tolerances.

There are some way to measure antenna resonance but first rule have to be that we may not to over-burden input LC circuit by direct measure instrument connection in a way to change his resonate frequency.

So we will try to measure without to over-lasting antenna circuit. Maybe you have or can lent some sort of reliable audio signal generator or signal generator for general use. If so, you first wind your testing transmit antenna from about 10 turns (1mm Cul) 10cm in diameter (or 10 turns on ferrite rods) and connect such testing antenna together with serial connected 1k pot (trim to middle position) to generator output. Put generator output on unloaded (max peak to peak output) square signal (typically 15vpp). Now you have your testing measurement transmitter ready.

Put your AL707 "ON" and approximate it to test antenna at about 20cm. Now you start to gradually change generator frequency from 0Hz to about 35kHz and watch for react from AL707 speaker or led. If you catch signal, try to establish his maximum. Frequency at which signal reach his peak is resonate frequency of selected frequency position of your AL707. Try the same way to establish other two frequency. In case of strongest signal from receivers speaker you can use attenuator on signal generator to get weak signal or put AL707 so apart from TX antenna to get weak signal from speaker. By weak signal we can more accurate establish peak and by this more accurate resonate frequency too.

In case of no signal from AL707 you can first regulate serial pot to lower resistivity of about 100E, more approximate test antenna to AL707 and at the end try to open it and measure signal at amplification stage by mV-meter or scope. To prevent possible damage hope that this would not be needed.

After you establish all three of antenna circuit resonate frequencies your next step is transmitter adopted to middle of three frequencies (or on one of his lower harmonics).

Here may you suggest to buy very usable testing instrument Portable frequency counter with possible use as field strength meter. You can search for it on eBay under name "GE FC-1 Portable Frequency Counter 10Hz - 2.6GHz". Usable to detect in-depended of transmitter and receiver resonate frequency of TX antenna and cheap.

Thank you very much for your help WM6.
The only thing that I have to ask you to explain me better is:

....After you establish all three of antenna circuit resonate frequencies your next step is transmitter adopted to middle of three frequencies (or on one of his lower harmonics). ....

Do you mean that if the lower freq. is 9khz and the higher is 10khz then the Tx must be adopted at 9.5Khz?

[J_Player]

Originally Posted by g-sani

Thank you very much for your help WM6.
The only thing that I have to ask you to explain me better is:

....After you establish all three of antenna circuit resonate frequencies your next step is transmitter adopted to middle of three frequencies (or on one of his lower harmonics). ....

Do you mean that if the lower freq. is 9khz and the higher is 10khz then the Tx must be adopted at 9.5Khz?

Hi g-sani,
Look what Qiaozhi posted:

The Gold Gun has 3 ranges:

1. 9.5KHz for long distance and weak EM fields.
2. 26.7-27KHz for USA.
3. 19.2KHz England, Philippines, Greece and USSR.

From this information, you need only one frequency for Greece to find the same VLF frequency you saw before.
19.2 KHz is the oscillator you want. This is much simpler than to build a variable frequency oscillator, and the antenna can be tuned for this frequency so it will send a strong signal at low power. Of course, you will want to make adjustments to find the exact tuning that gives good reception at your gold gun. See the WM6 post for this.

You could also build a transmitter that sends all 3 frequencies if you think this will help.

Best wishes,
J_P

[WM6]

Originally Posted by g-sani

Do you mean that if the lower freq. is 9khz and the higher is 10khz then the Tx must be adopted at 9.5Khz?

No, calculated middle frequency will be out of RX antenna resonance. We use real resonate frequency - one of three.

Exactly as J_P explain to you.

[g-sani]

ok I think I got it right this time.

[J_Player]

Originally Posted by WM6

Yes, but huge changing in propagation (like changing wave polarization etc) are in first line characteristic of very high frequency band as UHF not in VLF/ULF band. By local small transmitter we find some others aspect of problem. We are searching for weak source of reflected signal and at the same time we have in vicinity relative strong source of transmitted signal at the same frequency which cover weak target signal and disturb successive search . This is why I repeated that 0.3W is far enough and even too much for successive search. This is why we need as much as possible directive RX antenna to suppress direct TX signal in combination with some tricks and searching skill.

If we compare UHF and ULF frequency band from reflectivity view UHF are better to detect especially small target in air because of its directivity and worse to detect something underground because of his weak penetration ability, on other side ULF are weak on directivity and so worse to detect something in air but way better to detect something underground because of his excellent penetration ability in soil. Theoretically ULF radar can detect invisible objects (objects behind of hills or behinds of horizon) which UHF radar cannot. This is why ULF can reach targets on unusual way and why we speak about importance of RX sensitivity and Rx antenna directivity.

Hi WM6,
What you say about ULF radar is very interesting. ULF has a very large wavelength (many km) which makes it hard to image any small object from interference/reflection in the way microwave radar can. But the ground penetration is excellent for very large things. If you wanted to use RF to detect things in the ground, then VLF would be more suitable because the wavelength is shorter to allow better resolution of the buried object. As you increase the frequency, the resolution improves but the ground penetration is less. So a treasure hunter is looking for a frequency between the low and high that will have good ground penetration to maybe 1 meter, and good resolution to be able to locate where the anomaly is.

We know geologists use frequencies usually between 10-30KHz to map large rock fractures and ore deposits as well as fault lines. But they cannot find a buried coin 10 cm deep. Their signals are long wavelength that detect up to 25m deep in the ground or more.

But if we raise the frequency to 100 KHz, then the wave becomes shorter and will only penetrate to maybe 10 meters deep. At 250KHz, we expect even less depth, but better resolution of shallow targets.

My question is what is the best frequency you would consider for as treasure hunter who only wants to see to 1-2 meters depth maximum?
From the charts I look at, it seems that this may be very close to the lower AM broadcast band of 550 KHz.

Do you think an AM radio or modified AM radio at below 550 KHz could be used for looking at LF/VLF interference under the ground?
Also, is there a way to use these frequencies as a VLF radar?

Best wishes,
J_P

[WM6]

Originally Posted by J_Player

What you say about ULF radar is very interesting. ULF has a very large wavelength (many km) which makes it hard to image any small object from interference/reflection in the way microwave radar can. But the ground penetration is excellent for very large things. If you wanted to use RF to detect things in the ground, then VLF would be more suitable because the wavelength is shorter to allow better resolution of the buried object. As you increase the frequency, the resolution improves but the ground penetration is less. So a treasure hunter is looking for a frequency between the low and high that will have good ground penetration to maybe 1 meter, and good resolution to be able to locate where the anomaly is.

We know geologists use frequencies usually between 10-30KHz to map large rock fractures and ore deposits as well as fault lines. But they cannot find a buried coin 10 cm deep. Their signals are long wavelength that detect up to 25m deep in the ground or more.

But if we raise the frequency to 100 KHz, then the wave becomes shorter and will only penetrate to maybe 10 meters deep. At 250KHz, we expect even less depth, but better resolution of shallow targets.

My question is what is the best frequency you would consider for as treasure hunter who only wants to see to 1-2 meters depth maximum?
From the charts I look at, it seems that this may be very close to the lower AM broadcast band of 550 KHz.

Do you think an AM radio or modified AM radio at below 550 KHz could be used for looking at LF/VLF interference under the ground?
Also, is there a way to use these frequencies as a VLF radar?

As you say in this field we can find a lot of question and research possibilities that can lead to one of (for amateur) rare ways to get something like real RDL (Reasonable Distance Locator). Principle are simple, realisation not so.

To reach long distances it is allways better to use lower frequencies, because as we go higher more dissipation on earth surface occured. This is not only reason to go at lower frequencies, we amateur are limited by our experimetation to rare authorized frequencies for such experiments or we are out of law. So, for us, relative safe are EM wave experiments inside upper spectrum of audio frequencies, say abuot 20kHz.

For "about 20 kHz" frequencies we need only weak transmitter to reach huge distance because of very low surface dissipation. On other side weak transmitter do not push our very weak tracked signals "back to underground" from our antenna and cover it and false its direction by its own signal strenght. Distance propagation of those wavelenght not mean that we can detect something at miles and kilometers, as babbling scammers propaganda. No, we can discuss only about meters, provided that we build our devices so, that it is possible. Nor detection of single coin from distance of a meter or so is impossible under some circumstances (at first of coin orientation against directed Rx antenna). But at first we can locate by this method different underground metalic deposits and not small golden nuggets.

Additional hint: such "about 20 kHz" weak transmitter equipped with well build and tunned stacked vertical antenna we can put even in our backyard and search in circle on radiated terrain kilometers away from home equipped only with a receiver. In this case transmitter have to be weak as discussed yet and well adjusted to antenna to prevent disturb our neighbors by radiated harmonic interferences.

In general VLF wave are not less reflective from the same target (if we neglect diffraction) as UHF wave but are more dispersive in reflection so we get by multiple factor weaker signal from VLF reflection as by same ULF propagation. Reason more for sensitive receiver and extremly directive Rx antenna.

[Krzysztof]

Hi, WM6, J_player.
I have some ideas for discussion:
1. Tx antenna should be the characteristics of a vertical magnetic. For example, a low power 10mW may be an antenna coil structure feryt of basketball (max Q) upright position (at the high power nature ferytu turn into a piece of wire). Maybe some other magnetic antenna Slit (but size - it could be a bad idea) . I think that 1/4 lambda antenna or coil, has a large vertical leaf levels of radiation, and we do not want to receive the signal reflected from the surface only goal.
2. Can benefit from the popular timers 36kHz quartz and pure analog generator to minimize the distortion and
harmonics. Rx side, you can think of crystal ladder filter with the same X-tals
3. I think that AM 500 kHz bandwidth makes for great Skin effect (more superficial than deep). In addition, A3 gives random modulation signal strength at measurement. Any modulation of A1, A2, A3, A3A is amplitude modulation, which forces a large measure of time - averaging.
4. How about an antenna Tx / Rx Framework 1m x 1m placed horizontally 20cm above ground level to eliminate the capacity of the soil (detuning) and reduced mutual visibility (direct reception)
5. Do you not think that we are moving close to the technology 50 years ago and described by Mikebg in this forum?
Vy 73 Chris

[WM6]

Hi Krzysztof,

thanks, I think your ideas are worth to be seen.

Can you go a little further according your ideas and post here some graphic presentation of your ideas and maybe some schematic or diagrams?

Yes, we are talking about an old radio communication technology as mikebg rediscover it too, but if it work all is ok.

It work if proper builded and used, and, as we can see, even used by modern army in different way.

[Geo]

Originally Posted by Krzysztof

Hi, WM6, J_player.
I have some ideas for discussion:
1. Tx antenna should be the characteristics of a vertical magnetic. For example, a low power 10mW may be an antenna coil structure feryt of basketball (max Q) upright position (at the high power nature ferytu turn into a piece of wire). Maybe some other magnetic antenna Slit (but size - it could be a bad idea) . I think that 1/4 lambda antenna or coil, has a large vertical leaf levels of radiation, and we do not want to receive the signal reflected from the surface only goal.
2. Can benefit from the popular timers 36kHz quartz and pure analog generator to minimize the distortion and
harmonics. Rx side, you can think of crystal ladder filter with the same X-tals
3. I think that AM 500 kHz bandwidth makes for great Skin effect (more superficial than deep). In addition, A3 gives random modulation signal strength at measurement. Any modulation of A1, A2, A3, A3A is amplitude modulation, which forces a large measure of time - averaging.
4. How about an antenna Tx / Rx Framework 1m x 1m placed horizontally 20cm above ground level to eliminate the capacity of the soil (detuning) and reduced mutual visibility (direct reception)
5. Do you not think that we are moving close to the technology 50 years ago and described by Mikebg in this forum?
Vy 73 Chris

Hi Chris.
Do you mean something like the photo???

Regards

[Krzysztof]

Hi all.
Modest note attached.

Unchecked idea is to use my Fluxgate magnetometer as an Rx!
Always treated the VLF and the other as EMI, now you look at it differently.
Tx antenna gives the issue a magnetic field, propagated in the ground, when it is sufficiently stronger than the earths magnetic field in conjunction with GPS and "Vumate" or "Snuffler" we are better than many well-known German company.
Who else will join the storm drain?
Vy 73 Chris

[Krzysztof]

Hi Geo.
It looks like a mini two-box.
And I think the 2 antennas with a vertical magnetic polarity, the land
component preferably disperses component magnetic field the electromagnetic field.
Maybe someone is thinking of something better than the ferites
antenna.
Vy 73 Chris

[WM6]

Hi Geo,

you are main developer here. Are you done some test?


Yes Krzysztof, it is more clear to me now, what you suggest.
Except draving Ad.4: did you imagine RX or TX coils as a fixed scaning or mobile?

[g-sani]

It seems to me that many of you here know the tips to build an LRL using rf (Tx and a Receiver to go on target)
This theory is already proved that it works and all you electronics should have one ready in your home for your treasure hunting expeditions.
Instead of that you are looking for other ways of building LRLs when you never had any treasure discovered yet.
Forgive me but I don't understand you.
I remember Esteban said that it is working and I think also he put a very old pfoto somewhere of people using it back in the late '30s.
Well I will put it down again.
I used to owe once something like that and I said it before in some other thread that it was working allright.Some people don't believe me but what can I do about that.
I said to Geo that sometime I will give him the Rx(which I still have) to see if we can make a suitable Tx so to make it work again.
You see we placed it once underneath a tree and we took the Rx and went a bit far from the transmiter while trying to spot a target.It was raining heavily some hours before and water drops was coming down from the leaves.The result was a short circuit at the Tx and it stopped working.We sent it for service but...
They sent us a different LRL back telling us that they could not repair the Tx.I loved that LRL and I was upset when we received back a different one.
Anyway, this one works as well but now you have to be a bit of a dowser to go on target.
To tell you the truth I wouldn't mind of paying some money again for such an LRL and if anybody knows anything in the market please let me know.
Does anybody knows if MAGNACAST™ 5000 FORWARD GAUSS Metal Detector™ works on the same principle?

http://www.vernellelectronics.com/productinfo.htm#5000

[mikebg]

AL707 and AL718 are very primitive and imperfect compared to EM16 of Geonics, because they have no a second ferrite rod antenna for reference signal. The operating principle of EM16 is described in patent US3500175.

[WM6]

Originally Posted by g-sani

Instead of that you are looking for other ways of building LRLs when you never had any treasure discovered yet.
Forgive me but I don't understand you.

When, in disgrace with fortune and men's eyes,
I all alone beweep my outcast state
And trouble deaf heaven with my bootless cries
And look upon myself and curse my fate,
Wishing me like to one more rich in hope,
Featured like him, like him with friends possess'd,
Desiring this man's art and that man's scope,
With what I most enjoy contented least;
Yet in these thoughts myself almost despising,
Haply I think on thee, and then my state,
Like to the lark at break of day arising
From sullen earth, sings hymns at heaven's gate;
For thy sweet LRL remember'd such wealth brings
That then I scorn to change my state with kings.

Willy Shake (S.29)

[Seden]

MikeBG,

This is true. What I would rather use is an active antenna to pick up the reference signal and compare the phase of the ref. signal with the signal from the horizontal loop over the treasure or ore. Another idea that I've seen in Magnetotelluric patents is to observe spectrum in the audio range when you are over ore deposits. For treasure you would use higher frequencies to see the smaller objects. In lieu of that you could use a white noise generator to do the same with much better S/N for the same spectrum signature of different metals or ores.

Randy

[Krzysztof]

Hi of all.
I don't think so , that we're to clear forums as well bids of unfamiliar utilization present techniques not abnegating sie the old man vets. Yourselves ain't dowser , Respect those regular people whereas not swindler.
I not know gold gun , I think not , everybody they've entrance into nich as well wherefore bids of unfamiliar coinage DIY.
J_Player g_Sani.
To be sure best antenna is not they've big storing magnetically clearing switch pawn as well least radiation electricians over world ; 60 years before the communication was done ex antenna underground on figures 2 probes tributary margin ex generator engine-room undersized frequency communication (besieged troops ).
Wherefore coinage ex signal electric ex generator Tx until world is not worst.
J_Player.
Zone LF this dubious coinage. Exemplary transmitter Monte Carlo (225kHz, 200kW) premises (interference) transmitter Warsaw (227kHz, 1MW) heard on Nand France free past distances upwards of 1000km to automotive receiver wireless.
Wave worldly-minded superficial is not large what prompts breaking signal aims.
Yesterday wrong frequency quartz ex timepieces duty be 32768Hz.
I don't think so , that Tx generator to quartz 32kHz at least on often Tx clearing us ex the rubs and worries of life of stability.
WM6.
Account spool Rx clear mobil until scaning. Spool blanket 1m x 1m will correspondent , not refutes of utilization spools on the lines of MD average 30 - 40 cm , whereas depths yet never mind.
Receiver tenderheartedness 1 mikroVolt ex strait zones ex such quartz on strained serial duty be gross on hand.
Yourselves deal to spring coinage ex Rx on figures gradiometers fluxgate ( tenderheartedness some nT/m )- this so-so promisingly.
At least once EMI will be utilization.
Bids until tendering your coinage.
Best regards. Vy 73! Chris.

[J_Player]

Originally Posted by g-sani

It seems to me that many of you here know the tips to build an LRL using rf (Tx and a Receiver to go on target)
This theory is already proved that it works and all you electronics should have one ready in your home for your treasure hunting expeditions.
Instead of that you are looking for other ways of building LRLs when you never had any treasure discovered yet.
Forgive me but I don't understand you.
I remember Esteban said that it is working and I think also he put a very old pfoto somewhere of people using it back in the late '30s.
Well I will put it down again.
I used to owe once something like that and I said it before in some other thread that it was working allright.Some people don't believe me but what can I do about that.
I said to Geo that sometime I will give him the Rx(which I still have) to see if we can make a suitable Tx so to make it work again.
You see we placed it once underneath a tree and we took the Rx and went a bit far from the transmiter while trying to spot a target.It was raining heavily some hours before and water drops was coming down from the leaves.The result was a short circuit at the Tx and it stopped working.We sent it for service but...
They sent us a different LRL back telling us that they could not repair the Tx.I loved that LRL and I was upset when we received back a different one.
Anyway, this one works as well but now you have to be a bit of a dowser to go on target.
To tell you the truth I wouldn't mind of paying some money again for such an LRL and if anybody knows anything in the market please let me know.
Does anybody knows if MAGNACAST™ 5000 FORWARD GAUSS Metal Detector™ works on the same principle?

http://www.vernellelectronics.com/productinfo.htm#5000

Hi g-sani,
The Magnacast 5000 is said to be an AM transmitter using a loop antenna to send a signal to one side. Then a second small receiver loop is held in the hand to locate the hidden metal. I heard no information to show that the Magnacast 5000 works, or not works. You can only know by trying it to see. Forward Gauss does not mean anything. No electronics engineer or scientist has ever heard of forward gauss. It does not exist. This is only a word made by the manufacturer to make it sound like it is new technology. Also, I do not believe you will find multiplexing circuits inside this detector like the manufacturer claims. But I don't know for sure.

I would not spend money for this detector unless you see it finds hidden treasures first. The other detectors built by VR Electornics are believed to fail for finding treasure. Even Dell Winders said "...operating conditions deteriorated affecting the reliability of the instrument making it impractical for my use in 1988".

You can read more about the Magnacast 5000 here, where Dell Winders posts false information and tries to hide the truth about forward Gauss: http://www.geotech1.com/forums/showthread.php?t=13089

Best wishes,
J_P

[Geo]

Originally Posted by WM6

Hi Geo,

you are main developer here. Are you done some test?


Yes Krzysztof, it is more clear to me now, what you suggest.
Except draving Ad.4: did you imagine RX or TX coils as a fixed scaning or mobile?

Hi WM6,

I made it before 2... 3 years. I tested but i had problems. It had the ability to detect a big object at 30m but it was very sensitive North horizon, at distance between me and detector and from trees.
So i let it at the side .
Maybe at lower frequency to work better .... who knows.
I don't remember sure, but i think that it worked at about 800Khz.

Regards

[Krzysztof]

Hi Geo.
It issues me, that secret sticks (lie) in (to) in antenna with vertical magnetic polarization.
So as vertical feryt, we search something better.
And f max< 32kHz.
Vy73 Chris.

[WM6]

Originally Posted by Geo

Hi WM6,

I made it before 2... 3 years. I tested but i had problems. It had the ability to detect a big object at 30m but it was very sensitive North horizon, at distance between me and detector and from trees.
So i let it at the side .
Maybe at lower frequency to work better .... who knows.
I don't remember sure, but i think that it worked at about 800Khz.

Geo, are you tried to put your ferrite antenna in RFI protective housing made from can of beer (one side open) and connected to ground of oscillator?

[g-sani]

Originally Posted by J_Player

Hi g-sani,
The Magnacast 5000 is said to be an AM transmitter using a loop antenna to send a signal to one side. Then a second small receiver loop is held in the hand to locate the hidden metal. I heard no information to show that the Magnacast 5000 works, or not works. You can only know by trying it to see. Forward Gauss does not mean anything. No electronics engineer or scientist has ever heard of forward gauss. It does not exist. This is only a word made by the manufacturer to make it sound like it is new technology. Also, I do not believe you will find multiplexing circuits inside this detector like the manufacturer claims. But I don't know for sure.

I would not spend money for this detector unless you see it finds hidden treasures first. The other detectors built by VR Electornics are believed to fail for finding treasure. Even Dell Winders said "...operating conditions deteriorated affecting the reliability of the instrument making it impractical for my use in 1988".

You can read more about the Magnacast 5000 here, where Dell Winders posts false information and tries to hide the truth about forward Gauss: http://www.geotech1.com/forums/showthread.php?t=13089

Best wishes,
J_P

This is what I thought to be J_P.The rest of their detectors have nothing special to show.
Of course the same thing applies here.Try it yourself to get knowing the truth, as always.
Regards, g-sani