Vallon VMH3CS Mine Detector

[green]

Hi Eric,

We very much appreciate your efforts with the Vallon detector, and obviously it makes sense not to break something that's working so well. These detectors do appear to be hard to come by. Also, a peak inside probably wouldn't tell us an awful lot, particularly since the interesting stuff is mostly complex code hidden in a DSP.

Do you have any thoughts as to how they've managed to obtain such a good response to low conductivity targets with a 1.5mH coil? The accepted wisdom concerning PI detectors suggests that this should not be possible.

Hi Eric,

Second Qiaozhi's question. Wondering if sometime you are doing some target testing if you could include some lower conductivity targets. Piece cut from kitchen type aluminum foil(not heavy duty) 1x1 inch(1.6usec TC), 10x10mm(.6usecTC) and or a piece cut from the side of a aluminum soda can .25x.25 inch(1.4usec).

[Qiaozhi]

Hi Eric,

We very much appreciate your efforts with the Vallon detector, and obviously it makes sense not to break something that's working so well. These detectors do appear to be hard to come by. Also, a peak inside probably wouldn't tell us an awful lot, particularly since the interesting stuff is mostly complex code hidden in a DSP.

Do you have any thoughts as to how they've managed to obtain such a good response to low conductivity targets with a 1.5mH coil? The accepted wisdom concerning PI detectors suggests that this should not be possible.

[Davor]

These detectors will be coming onto the market in dribs and drabs due to upgrading of mine detection technology and downsizing of military forces and maybe they have a second life rather than being consigned to the dustbin.

Correct.
Unfortunately the minesweeper contractors in Croatia are in drags as their contracts are mostly hanging by a thread. I expect many more of these machines to hit ebay as more such companies bite the dust. Harsh times.

[6666]

Hi Eric, our son is in the Aussie army and currently on his 4th deployment in a foreign hostile country, I will attempt to ask him if he has used this detector in his job, he has been involved with similar devices used for clearing things that go boom.

[Ferric Toes]

Smart one will rather peek into a "box" and see how others done it, not just to make copy of it; but to learn something new.. eventually.
Ok... your device; your decisions.
But truth is this topic started very interesting and attracted huge attention... and just after few posts it diluted to pretty annoying "all the same" story.
Again; not my intention to disrespect nobody here, i just feel free to say my opinion loud and clear. Isn't that democracy?
I'm outta here... cheers!

The primary purpose of this thread was to investigate the possibility that the Vallon pulse induction mine detector could, in its retirement from military service, be an effective hobby detector for land and beach use. After all, even 10 years after it was introduced, it has some advanced features, a major one being effective ground balance. Being designed for military use in hostile environments, it is incredibly rugged, weather proof, dustproof and submersible to the top of the bottom shaft. Sensibly looked after it should last another 10 years in civilian use.

Having been involved in some magnetic soil studies and attended a conference in 2008 on detecting mines in difficult soils, I have read many of the reports on the use of various mine detectors in places such as Bosnia, Croatia, Iraq, and Cambodia. The Vallon was always very highly regarded for its performance.

Two years ago I purchased six VMH3CS search heads and shafts which has been thrown out as unfit for further service. 5 of the search heads turned out to be perfectly OK and one was cracked. It was the cracked one that I salvaged the swivel from, and is now mounted on the 11in search head recently built. Out of the shafts, by mixing and matching parts, I have 3 complete ones with internal cable and plugs. What I was never able to get until recently was the main control box of the VMH3CS.
Having being absent from the Geotech Forum for a few years I figured that someone might have tested a Vallon with coin, ring, nugget hunting, in mind; hence my initial post to see what the response would be.

These detectors will be coming onto the market in dribs and drabs due to upgrading of mine detection technology and downsizing of military forces and maybe they have a second life rather than being consigned to the dustbin. That is what I am investigating at present. The technical side as to how they work as well as they do is also interesting, but my facilities and expertise is limited when it come to programmed DSP. Someone else can investigate that if they wish.

From today's beach tests I am convinced that the VMH3CS is a good contender amongst other top PI units, inspite of the beach and weather conditions not being the best. I found two £1 coins which paid for two hours at the car park, plus fishing weights and other bits of metal. We did some depth tests in wet sand of US and UK coins but that is for another post.

[Geo]

Ivica, i believe that eventually Eric will present some pretty interesting things.
Let's be patient and let's wait (I'm and me impatient like you).
I am sure that at the end we will have earned enough from this thread, but I agree with you that everybody should say his opinion loud and clear.

[ivconic]

I don't get the impression from other posters on this thread that my posts are irrelevant. There will be many more on the testing and comparisons of the stock Vallon coil and ones that I will make. Right now I will make the point that there will be no photos of the inside. The reasons are these.

The VMH3CS is a specialised detector and built to military standards. Prior to coming into PI metal detectors I worked on military airborne radar equipment, so I know something about the standards in engineering that apply. Without a service manual, taking the Vallon apart is not easy and irreparable damage could result. I have a second Vallon which had a very rough time in field used and I carefully worked out the necessary sequence to open the case. The electronics is in a sealed screened box and could not be removed without damage. That is as far as I got. The detector is now being reassembled and the case, shaft etc. cleaned up.

Personally, I am not in the business of copying other manufacturer's detectors. I will look in a general way at what others do and maybe do a few measurements across the coil to investigate waveforms, current, timings, LRC etc. The knowledge that I would gain by examining the circuit boards would be very limited, particularly SM multilayer types and controlled by a programmed micro. What I have done thus far is non-destructive and does not impinge on patents, copyrights, or confidential commercial material.

As Davor correctly noticed; no disrespect from me on your account, not at all.
I am just a bit annoyed with so many posts and words and no pictures and photos yet.
Your chances to investigate it in details, according only to what you heave available out from the box (coil connector), are pretty narrow and limited in that matters.
All you can do is to scope signal and it's features... which are few any you already did it. Do we know something more than we knew before? Not much.
"...I am not in the business of copying other manufacturer's detectors..."
I am. Not exactly on it's "dark side" but only in educational purposes.
Ain't no better way to learn things than using theory&practice altogether on live example.
Besides... what is older; chicken or egg?
Who copied whom? Who was the first? Who invented front end? Pulsing circuit? Audio? Sampling?
Those questions are completely pointless today. Because no one can come out now and say "i am original designer" completely.
Smart one will rather peek into a "box" and see how others done it, not just to make copy of it; but to learn something new.. eventually.
Ok... your device; your decisions.
But truth is this topic started very interesting and attracted huge attention... and just after few posts it diluted to pretty annoying "all the same" story.
Again; not my intention to disrespect nobody here, i just feel free to say my opinion loud and clear. Isn't that democracy?
I'm outta here... cheers!

[Davor]

The electronics is in a sealed screened box and could not be removed without damage.

Is there any chance to see how it looks inside? Do you by any chance have any photos from the phase of opening the damaged box?

I believe ivconic was just anxious to see it and meant no disrespect.

I also don't believe in copying other people's work. Finding out why something works well, and designing your own solution that does the same or better is something I do believe in. On the other hand, we all seen the entrails of machines that competed against Vallon, and lost, and it would be educational to see what makes it tick. Vallon most obviously put some interesting ju-ju in that small box, and it is European.

[daverave]

Hi Dave, Correction, you can buy an untested VMH3CS for £400. I checked, and they do not have the full 63 page instruction manual, only a plastic laminated field card.

There is only one VMH3CS(EF) and that is my fully tested and refurbished one with the 11in search coil which I finished yesterday and will be tested on the beach today at low tide (11.50am). At some future point it will go to Australia for testing in the worst mineralised ground in the world.

Hi Eric....i forgot about the ebay VMH3CS being untested...i think for the price it would be worth taking a risk if i were in the market to buy one....should be interesting to see what depth you get in wet sand with your larger coil

[Ferric Toes]

50 hundreds annoying and irrelevant content pages more here... and eventually we'll deserve the rare luck to see posted photos from the inside of the damn unit... i guess?
Eric... earlier when i advised you to take it easy... i didn't really mean that easy!
It is tough to accept that one of the most brilliant PI expert here is constantly hesitating to open damn toy and take few shots from the inside!?
Is it so hard? Maybe dangerous?
Sheeeeeeeeeeeshhhhh!

I don't get the impression from other posters on this thread that my posts are irrelevant. There will be many more on the testing and comparisons of the stock Vallon coil and ones that I will make. Right now I will make the point that there will be no photos of the inside. The reasons are these.

The VMH3CS is a specialised detector and built to military standards. Prior to coming into PI metal detectors I worked on military airborne radar equipment, so I know something about the standards in engineering that apply. Without a service manual, taking the Vallon apart is not easy and irreparable damage could result. I have a second Vallon which had a very rough time in field used and I carefully worked out the necessary sequence to open the case. The electronics is in a sealed screened box and could not be removed without damage. That is as far as I got. The detector is now being reassembled and the case, shaft etc. cleaned up.

Personally, I am not in the business of copying other manufacturer's detectors. I will look in a general way at what others do and maybe do a few measurements across the coil to investigate waveforms, current, timings, LRC etc. The knowledge that I would gain by examining the circuit boards would be very limited, particularly SM multilayer types and controlled by a programmed micro. What I have done thus far is non-destructive and does not impinge on patents, copyrights, or confidential commercial material.

[ivconic]

you could always buy a VMH3CSEF on ebay for the bargin price of £400 UK pounds

Huge chances to pay for detector and get .... cat in a sack!
Eric has rare luck to get device in good shape.

[Ferric Toes]

you could always buy a VMH3CSEF on ebay for the bargin price of £400 UK pounds

Hi Dave, Correction, you can buy an untested VMH3CS for £400. I checked, and they do not have the full 63 page instruction manual, only a plastic laminated field card.

There is only one VMH3CS(EF) and that is my fully tested and refurbished one with the 11in search coil which I finished yesterday and will be tested on the beach today at low tide (11.50am). At some future point it will go to Australia for testing in the worst mineralised ground in the world.

[daverave]

you could always buy a VMH3CSEF on ebay for the bargin price of £400 UK pounds

[ivconic]

Maybe Eric don't like to give more info about this detector.....
Perhaps it is a matter of conduct to the other manufacturers

Maybe so...

[Geo]

50 hundreds annoying and irrelevant content pages more here... and eventually we'll deserve the rare luck to see posted photos from the inside of the damn unit... i guess?
Eric... earlier when i advised you to take it easy... i didn't really mean that easy!
It is tough to accept that one of the most brilliant PI expert here is constantly hesitating to open damn toy and take few shots from the inside!?
Is it so hard? Maybe dangerous?
Sheeeeeeeeeeeshhhhh!

Maybe Eric don't like to give more info about this detector.....
Perhaps it is a matter of conduct to the other manufacturers