Full m/lab SD2000 schematics

[Mechanic]

Excellent! Knew you could figure it out!

Of course you are just building this for educational purposes aren't you.....!

Cheers Mick

[victor68]

Yes...and are a lot of thinks to learn. I am old fashion and I have a feeling about detectors...the best way is to stay in analog circuits. Regards, Victor.

[Kev]

They must of thought that it brings good luck to add 2 X 4148 diodes as a protection feat. Pity that these diodes are never exactly the same as each other and if a big spike came down the lower voltage drop of the two will conduct and be converted into a tiny little bit of conductive slag. My advise is to get rid of the diodes as we can do without the extra 10pf of capacitance at that part of the circuit. The Goof is in the bias setup of the 2 transistors, the set point is wrong and upsets the noise figure and the available low signal gain. There are other technical (not quite right) components in other parts of the circuit, especial on the gain settings on some opamps. Some of the stages should have rc networks rather than a straight resistor to cut out a lot of artifact noises being generated by the detector itself when the input signal causes problems with the slew rate of some components.

Anyway, thanks to Zed for putting up a decent schematic, much better than the hotch potch of drawings from past contributors.

Other ML things that we have at our disposal is circuits for the 2100 2200 but not the later ones (being worked on) Source code for the above two and I think the code has been cracked for the 3000 series.

We do not want to post too much at this time as ML will go into meltdown and the stock options will go to zero. They just need to be slowly softened up like the old SD2000 popping up and saying "Hello Boys".

Just think that if Eric Foster or Corbyn patented their work then we would not have a M/L.

Hi,
Does anyone know of a published solution to this?
Are there any "long tail" specialists here?
I may need to swap out components and see, but that's a bit of wall beating, much better to understand the theory!
Does the normal base bias theory hold? Then why have they minimally loaded the input with 33K, is this the goof?
Did they find that the LM394 hfe variations required it, or Oz ground variations required it?
Why is the gain so low in the second stage, is this where more sensitivity can be wrung out?
Why such a weird tail current regulator?

Anybody care to share their hard won knowledge on these questions, this old crust would surely appreciate the saving what little of life remains not scratching the head and lifting and tearing tracks!



Cheers Gentlemen
Kev.

[technos]

Excellent! Knew you could figure it out!

Of course you are just building this for educational purposes aren't you.....!

Cheers Mick

You know, I am quite disappointed in this statement. Perhaps you could explain yourself better. I know I made a posting about this four years ago http://www.geotech1.com/forums/showt...408#post114408

Maybe you could point out what US patent for this detector is still in effect, because I know that it has no copyright protection under US law. I've looked under the patents that are posted elsewhere on this site, and any patent that could have covered this detector expired back in 2013. Carl really needs to update the first 2008 post he made in this thread. Interestingly, two of Minelab's patents had already expired then.

So there is nothing from stopping someone from making clones of these machines and selling them on any street corner they desire. Of course, they can not use the Minelab trademark, but I bet they could use the number "2000" to describe it - as numbers are not - trademarkable - as the US federal courts have decided previously (from the 80386 cpu days).

I have wrangled over this with others, but no amount of wishful thinking by those with specific interests can change the law.

[mickstv]

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[Kev]

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[WM6]

Please, make your posts in English!
Here are the Forum Rules ->
http://www.geotech1.com/forums/showthread.php?t=10526

[Carl-NC]

You know, I am quite disappointed in this statement. Perhaps you could explain yourself better. I know I made a posting about this four years ago http://www.geotech1.com/forums/showt...408#post114408

Maybe you could point out what US patent for this detector is still in effect, because I know that it has no copyright protection under US law. I've looked under the patents that are posted elsewhere on this site, and any patent that could have covered this detector expired back in 2013. Carl really needs to update the first 2008 post he made in this thread. Interestingly, two of Minelab's patents had already expired then.

So there is nothing from stopping someone from making clones of these machines and selling them on any street corner they desire. Of course, they can not use the Minelab trademark, but I bet they could use the number "2000" to describe it - as numbers are not - trademarkable - as the US federal courts have decided previously (from the 80386 cpu days).

I have wrangled over this with others, but no amount of wishful thinking by those with specific interests can change the law.

Most likely the SD2000 is no longer under any patents, if it ever was. When the schematic was originally posted ML contacted me and asked me to remove it. When I asked why, they cited an expired patent. I pointed out the patent had expired and, even so, posting a schematic does not violate even legitimate patents, only producing the item is a violation. I recall they cited other vague and undefined legal issues and that I was inciting people to violate patents, which is actually part of patent law.

I told ML the schematic was staying, and to short-cut the need to hire a lawyer I simply offered to include a disclaimer. I think ML realized they had no leg to stand on and that I wasn't going to easily fold, so they accepted the situation and went away. Probably there's nothing to stop anyone from making a clone (but not a counterfeit), except that ML could decide to make it an expensive venture.

- Carl

[Kev]

Care to elucidate Unregistered?

[WM6]

Great, that you are not surrender in this case, Carl.

But you live in USA, if you live in Australia, the outcome appears to be different.

Example: when Doug posted two photos of (I think ->) GP Extreme bare (no white painted) board on AEGPF, it did not take long, to "convince" him, how they should, faced with "arguments", to withdrawn such "IP sensitive" material.

[Carl-NC]

No, I disagree, with photos of unpainted PCBs the case is even more elemental. There is not only no leg to stand on, there is not even a toe, so you simply say, "They stay."

[Qiaozhi]

Care to elucidate Unregistered?

"Unregistered" will be unable to reply to your posts, as everyone now has to be registered to access the forum. You can thank the spammers.

[Kev]

"Unregistered" will be unable to reply to your posts, as everyone now has to be registered to access the forum. You can thank the spammers.

Rhetorical question really, just to underscore the fact, the "Goof" has yet again been safely buried.

[ivconic]

My logic is quite different.
If i wasted my hard earned money to buy any product, in this case ML product, once i payed for it; it is my own property, and therefore i can do with it whatever i want.
If they don't like that; they shouldn't sell those at first place.
I can open it, i can copy it, i can make copies and try to sell them.
Those copies are not their property but mine own.
You think this is maybe wrong and bit weird attitude, but think twice.
Not only that they robbed you for average product, not only that they attracted you with pure lies to waste your hard earned money; but also they want to take full control even further over your using of that product!
It's not gonna happen folks, at least not with me.
Once i give my money for something; it is fully mine and under my full control.
And if they want to protect their "intellectual" property (what a joke, especially in ML case); than they should use more brains and less brute force.
For example; they should make the device which is impossible to copy... or at least very hard to copy and impossible to huge majority.
"Intellectual property" especially in md category is pretty tough case to define. Which idea is which. Who done that first. Who copied whom. Etc...
The one who first used opamp at md frontend than may claim his own patent on that, right?
So ML should also be prosecuted for using opamp in frontend at their toys, right?
Also... why don't they go and try to protect their "rights" in China?
Complete BS... all this fuzz around ML and their rights!
I don't give a s..t about their rights, same way as they don't give a s..t about my rights too.
Just visit their page and see tons of lies they are spreading around. Wasn't that called a fraud?
Who's gonna be responsible for all their lies and frauds? Our hard earned millions?
C'mon! Give me a break!

[ivconic]

Forgot to point one true fact,
copy; whatever it was made good: can't replace original nor can be sold at same price as original.
Original is original, copy is just copy.
So dedicated ML users will never ever think to give even a dime for somebody's copy.
Brand is brand. We, people, are usually dedicated to brands even if their models are not always best made.
So i don't see reasons for to be so protective.
I think it is even much better if some model and brand are widely copied among enthusiasts; because it is obvious proof that it is desirable in brains of majorities.
Next; such desirability will always lead to future wishes to have original, sooner or later.
I made copies of dozen Tesoro models. But i always have strong wish to have Tesoro originals in my collection.
Copies are there for fun and for educational purposes, originals are there to keep them and to love them.
That's why ML looks even more stupid in my eyes.