Real Metal Detectors

[michael]

Hi friends.
I'm back from a hard digging on a hard soil; only 3 meters progress for 4 nights. puuuufffff. what a wild, tiresome and bad condition.

Michael - if you tap the top of the white box, does it sound hollow, or do you think it's full of potting compound?

in your answer I tapped White chamber carefully, all parts sound be full of compounds except to the part I circled.

[Qiaozhi]

Hi friends.
I'm back from a hard digging on a hard soil; only 3 meters progress for 4 nights. puuuufffff. what a wild, tiresome and bad condition.

in your answer I tapped White chamber carefully, all parts sound be full of compounds except to the part I circled.

In that case, even if you sawed the top off the module, it is unlikely that we would learn anything.

[BillA]

Did I understand that this is an all metal MD ?
or is it a magnetometer ? (ferrous only)

it is not a US product for the many reasons described

has anyone searched in Spanish or Portuguese ?
it would appear to be a clone of something, why the misdirection ?

Bill

[Max]

Did I understand that this is an all metal MD ?
or is it a magnetometer ? (ferrous only)

it is not a US product for the many reasons described

has anyone searched in Spanish or Portuguese ?
it would appear to be a clone of something, why the misdirection ?

Bill

Hi,
it's probably a clone of an existing PI MD, probably an industrial MD modified to be a depth kind.

The mislading informations are probably there for many reasons like:

- manifacturer wanna hide himself, that's cause of previous bad fame with other devices or cause don't wanna be involved in copyrights and patent issues that could lead to a lawsuit and relative money loss. People read forums like this... learn about good and bad companies and products and I think just really naive people today, with all these informations available by Internet, will buy from a bad famed manifacturer.

- manifacturer wanna make people belive that device is a genuine USA product, from military arena: it's common belived that US military stuff is hi quality (infact, it is) and very special technology (this also). People are prepared to spend much money for a USA made , military device... and these could spend many thousands US dollars for the unit. Who wanna pay e.g. 10000 usd for something made in China or Brazil ?

- manifacturer cut this way any relationship with device, thus making impossible for the customer asking e.g. for servicing etc this free other resources cause they could haven't any customer service... abroad labs etc... expecially they haven't declare where their offices are located etc

- the celeron sticker is probably just another way to make people belive there's something magic... inside the box.

Now... all that doesn't mean device doesn't work as explained, though it's probably a cloned device made somewhere far from USA.

Kind regards,
Max

[BillA]

Thanks Max

I'm thinking it is a magnetometer, nothing more.
If so it can be compared to any other mag, specs all over.
The comparisons to date are with other 'treasure hunting' devices; it would be more interesting with industrial mags whose performance is known.

Michael
Did you make your 2m coil ?
What was the design basis ? (same as the 1m but larger ?)

Bill

[michael]

Hi friends. due to a friend recommend I tried to prepare pictures of any possible part inside for urgent time if needed to be replaced, know the exact value of components. I measured most Resistors and wrote Caps value & diode numbers.
I took much better quality pictures. I noticed that some info of 2 IC ( in MDL board regarded as transistor) maybe recognizable. I pulled a wet cotton on ICs then appeared better then results became these that you see.
for biggest transistor it seems impossible, no way. for 8 pin IC as you see very poor info appeared.
Is here any body can help and recognize them? (I mean at least 2 Tr). I know this is entirely usless to make a copy of that but can be a help to me for my rainy day.

Thanks in advance.

[Max]

Hi friends. due to a friend recommend I tried to prepare pictures of any possible part inside for urgent time if needed to be replaced, know the exact value of components. I measured most Resistors and wrote Caps value & diode numbers.
I took much better quality pictures. I noticed that some info of 2 IC ( in MDL board regarded as transistor) maybe recognizable. I pulled a wet cotton on ICs then appeared better then results became these that you see.
for biggest transistor it seems impossible, no way. for 8 pin IC as you see very poor info appeared.
Is here any body can help and recognize them? (I mean at least 2 Tr). I know this is entirely usless to make a copy of that but can be a help to me for my rainy day.

Thanks in advance.

Hi,
uhm... do you ask for an impossible mission ???

Does your message selfdestroy within 5 seconds ???

Ok... the scraped labels are not so useful... what's useful is what I can see , chars and numbers.

1. is an STM made mosfet, BUZ series... something e.g. BUZ11 or BUZ21 and the like... cannot be more accurate cause I see nothing more than that. Probably is an N-channel kind, but to know better you have to make your measures there.

2. is probably a voltage regulator... maybe L7805CV and the like... I don't see its label... but position of ST logo seems indicate that... look at picture 2 and you'll see/read "MOROCCO" at middle like in yours. You can check with a multimeter for regulated voltage at pin3, output...just to be sure of what is it.

3. This is very tricky... all about removed: I recognized the case as a TI part, probably is an NE5534AP made by TI. The last char there.... is related to production plant and similar information... proprietary code of TI. It seems there's an "N" as first char of IC label but maybe you'll see better using a magnifing lens.

Now that all this Sherlock Holmes' stuff is performed... could I light that dang cigar !?

What to say... seems nothing from MARS inside!

Kind regards,
Max

[michael]

Hi, thanks a lot Max, good, very good. Good help.
if you remember, I never cared about where it's made the important thing is it really works, terribly works now made in Morocco or Afghanistan, not important, and if so, what a shame on famous firms in giant industrial countries without such production. it's not important is made in USA, mars or country from Africa. it works, that's enough.
I'm a picky in this affair and don't approve a device simply.
believe me it is worth of course for those who search blindly on wilderness and remote areas for big lost treasures at great depths.
When I focused on USA made was just to give a point or a direction to find maker and based on what I'd heard its' origin was America.
I paid for after about one day different tests on that which it easily and successfully passed.

Max on second IC at end I see “8” you mentioned is L7805CV I see "WCC850104" end number is “4”!!! or this doesn't matter?
BTW Max; do you have any guess for the biggest Transistor you see here? Or have a limitation list of probable options or no have a huge list of similar stuff?
of course these are not enough but for me be informed it is better than unknowing.
I thing in back of LCD I see some tiny microchips and highly possible inside white chamber be such components.

[Max]

Hi, thanks a lot Max, good, very good. Good help.
if you remember, I never cared about where it's made the important thing is it really works, terribly works now made in Morocco or Afghanistan, not important, and if so, what a shame on famous firms in giant industrial countries without such production. it's not important is made in USA, mars or country from Africa. it works, that's enough.
I'm a picky in this affair and don't approve a device simply.
believe me it is worth of course for those who search blindly on wilderness and remote areas for big lost treasures at great depths.
When I focused on USA made was just to give a point or a direction to find maker and based on what I'd heard its' origin was America.
I paid for after about one day different tests on that which it easily and successfully passed.

Max on second IC at end I see “8” you mentioned is L7805CV I see "WCC850104" end number is “4”!!! or this doesn't matter?
BTW Max; do you have any guess for the biggest Transistor you see here? Or have a limitation list of probable options or no have a huge list of similar stuff?
of course these are not enough but for me be informed it is better than unknowing.
I thing in back of LCD I see some tiny microchips and highly possible inside white chamber be such components.

Hi,
the "MOROCCO" there is just about where's located production plant of component: STM has production plants in MOROCCO , as well as e.g. MALAYSIA that's why you read it there.

This doesn't mean device was assembled in Africa: I belive there's high probability (90%) device is a South American made clone of something else.

The "8" you read at middle of second is part of a production code... about e.g. date of production, lot, country, plant, line etc... all this used by manifacturer of semiconductor to retire (if needed) defective products... simply to identify all such params but not device kind; device kind is in first row, scraped away...we cannot read it: use a multimeter and check for voltage at pin3... that's will say wich voltage there is and so about device label...if e.g. a 7805 or different one.

The big case you posted I'm not sure is a transistor: let me explain... that case is employed in various ways and for e.g.

-power BJT
-power IGBT
-some "unusual" mosfet devices
-power double fast recovery diodes (like MBRxx series) used in e.g. DC-DC converters

In any case, that package is for power stuff that run at high voltage... so if BJT could be , as example, a flyback driver like e.g. S2000. Unfortunately the label is completely scraped and so you can make just wild guesses unless you desolder it and check with multimeter or some other tools...that will be an "invasive" procedure...

Kind regards,
Max

[michael]

Hi. thanks again Max. on MDL board this big one's regarded transistor (T1) as you see in Pic from above.
when you think it's for high voltage purpose don't have any option
or suspect to any component? if no, can tell by this time S2000 is best suspect.
another thing is about one cap beside the small one.
it seems value intentionally has been erased and wrote number 3. what's your guess?

[Fred]

Hi,
Yes i completely agree with the big one, probably a big HV (mosfet?)transistor, anyway it is the one that connect to the coil.It is connected in darlington config,with the small bc548-like one
Also the 2 other ones are probably regulators,their center pins are grounded.One must be 5V , the other must be 9V or less if supply is 12V...
We would need better pics to trace the circuit,some parts are hidden...
BTW Max, the big cap is connected directly to supply so no secret technology here ...In fact the only HV present here would be the one from the coil itself.In fact the coil is connected to + and transistor ground it,
l looks like a very simple design.If there is a secret it is in the signal processing,not in the hardware.
Averaging values may be the secret...
Regards,
Fred

[Fred]

it seems value intentionally has been erased and wrote number 3. what's your guess?

Hi,
No, that one look normal to me , 3pf cap ...
Regards,
Fred.

[michael]

Hi, Fred, thank you. are sure it's 3 pf? then what's the smaller cap?
I don't know if such pictures be help as many things are inaccessible.
here like before that I did just for your request(surely cannot be a progress. only finding maker is final help.), again put some from different angles in respond to you not some guys who think can get result with provoking.
BTW fellows, don't you think this board is double sided?

[Max]

Hi. thanks again Max. on MDL board this big one's regarded transistor (T1) as you see in Pic from above.
when you think it's for high voltage purpose don't have any option
or suspect to any component? if no, can tell by this time S2000 is best suspect.
another thing is about one cap beside the small one.
it seems value intentionally has been erased and wrote number 3. what's your guess?

Hi,
I agree with Fred about cap... seems 3pF, not relabeled. If you think it's relabeled cause see it better... well could be also: some extreme tuning could be at selecting caps too... then relabeling according to some scheme they use... though seems really strenge thing if so. I think there are all ordinary components.

About the big transistor: in early designs of PIs bipolar transistors where used cause the lack of mosfet devices... then , when mosfets become popular and offered improved performances they were the number 1 choice in PI switching devices. At that ancient times... most CRT hi voltage BJTs were employed: look at old Corbyn's article in wireless world.

Now... the thing there... is connected at coil , right ? If so... must be a switching device and , cause few mosfets really use that package, I think could be some hi voltage BJT or IGBT.

Now... Fred stated there's a darlington connection there (I've not checked circuit) and then it MUST be a BJT.

If so, it's probably something like in old CRT flyback sections... a huge e.g. triple mesa , hi voltage NPN... S2000 is an example but could be anything similar.

That BJTs are rated usually 1200V or more breakdown... very high... and usually have very small capacitance , allowing fast switching. If so, your PI probably inject very large amount of current in coil... then the hi voltage spike is VERY fast cutted by breakdown at something 800-1500V... and then evenlope at out of preamp is integrated etc... probably using a numeric alghoritm.

Could this lead to better performances than with mosfets ??? Yes, sure.

Consider most PIs have 400V breakdown and di/dt pulse duration is limited by that: when peaks reach 400V, current peak shape stay there as long as signal is over 400v... longer time than with breakdown at 1200V, in few, simple words: allowing a greater breakdown allow wider , always di/dt, transient seen at target... wider decaying evenlope allowing increased response at RX, you can integrate better and that will stay at higher S/N than 400V.

Unfortunately there are too few data to understand how the various pieces work together.

Kind regards,
Max

[michael]

and I think with this one all aspects of this part(uncovered) be recognizable.