Full m/lab SD2000 schematics

[bugwhiskers]

Hi Kev,

I was thinking about that "sweep" idea the other day for exactly the same reason. If a micro is used it can "remember" where it saw the biggest signal strength and if the user presses a button it will go back to and hold that combination of timings to allow pinpointing.

Re-working the 2000 to micro-control would halve the component count.

regards
bugwhiskers

[bugwhiskers]

Sorry Bugwhiskers but i beg to differ,my current experiments involve large amounts
of coil current and sampling during the fly back and i have a hot rock
that gives off a conductive response from 20 to 100 mv straight off the coil,
no pre amp,now im not saying that will be the case with a standard pi but it
leads me to believe that a conductive response is something that i will have
to deal with as i design and explore.

Zed

Hi Zed,

If you refer to Corbyn he says the decay curve is a sum of exponentials. They would be the curve generated by the coil in air, the curve change wrought by the ground matrix and if a target is present the change wrought by it. Better conductors producing a flatter more extended curve shape change.
Corbyn synthesised a signal that approximated "ground" and subtracted it. ML use the difference between a long and a short pulse to create their synthesised ground signal. None of the aforementioned methods are perfect even if carefully adjusted especially if the ground is extremely variable.

A couple of years ago I was playing with varying the TX on time so that the back emf was below the MOSFET's avalanche diode voltage. What I noted was a change of as much as 20 volts when different target types were in proximity. I am still of the opinion that there is much to be discovered in this field

regards
bugwhiskers

[Carl-NC]

Everyone please read the notice I've added to the first post of this thread.

Thanks.

[ZED]

So what your saying Carl is hosting the schematics isnt a violation of the patents but... building projects
based on the schematics is.
I fail to understand why building projects that are based on someone elses patents should be veiwed
as a patent infrigment,the experimenter is not profitering from the project,if anything the experimenter
in all probability will get a better understanding of a patent,see its short comings and likely find a better
approach to the final solution,maybe thats what there afraid of.
Not to mention some of there embarrassing business decisions coming to light.
Did they contact you before or after the subject of windows.
I would like to also point out that it is NOT my intention in anyway to undermine the efforts and work
that Minelab have done and continue to do in any way,i like there detectors and have done very well
by them,the SD2000 is a 12 year old format that Minelab dont use or produce anymore and the SD2000
schematics were posted purely for educational and reasons of interest.

Zed

[bugwhiskers]

I'm with you Zed.

ML have built on earlier work by Corbyn and Foster. If it weren't for the unselfish sharing by these early PI pioneers ML wouldn't be where they are today.
One can only hope that out of the ranks may come someone who can build on what ML and the real pioneers have done and take the art a step further.

regards
bugwhiskers

[Carl-NC]

So what your saying Carl is hosting the schematics isnt a violation of the patents but... building projects based on the schematics is.

Per Title 35 of the CFR, which specifies patent law:

"whoever without authority makes, uses, offers to sell, or sells any patented invention, within the United States or imports into the United States any patented invention during the term of the patent therefor, infringes the patent."

and

"Whoever actively induces infringement of a patent shall be liable as an infringer."

So, you're really not allowed to even build a patented device, even for personal evaluation and experimentation. I've always thought this was overly restrictive, and is probably widely ignored in industry.

The second part concerning "inducement" was brought up by Minelab. They believe that my hosting the schematics encourages patent infringement. If that were true, then anyone who hosts patent documents must also be guilty, as a patent document (by necessity) gives all the details anyone would need to violate the patent. The USPTO, by its very nature, induces patent infringement.

I would like to also point out that it is NOT my intention in anyway to undermine the efforts and work that Minelab have done and continue to do in any way,i like there detectors and have done very well by them,the SD2000 is a 12 year old format that Minelab dont use or produce anymore and the SD2000 schematics were posted purely for educational and reasons of interest.

Yes, I pointed all this out to them, and more.

I suspect that Minelab will not find this worth their time. As I said to them, the cat's out of this bag, and has left the neighborhood. Heck, he's already traveled round the world!

- Carl

[bugwhiskers]

Hi Carl,

I guess the next chapter in this saga will be ML's legal firm, the famous "Martin Barton and Fartin" rattling their sabre in your ear.

Just maybe the cat has figurerd out a way to GB without infringing their patent and without the holes/windows during his world trip.

regards
bugwhiskers

[bugwhiskers]

Hi Carl,

"The second part concerning "inducement" was brought up by Minelab. They believe that my hosting the schematics encourages patent infringement."

I'd take this sabre rattle with a large grain of salt.

Would a jewellery shop owner by filling up his shop window with gold and diamonds be "inducing" a ram raid or even offering an "encouragement" for theft ?


regards
bugwhiskers

[geshi]

Zen i suppose you are not minelab's favorite in this moment. Considering its and old device i wonder how they will feel if they see SD2200 with the source code here.

[Unregistered]

Patents

Ho,
So if you can't build for your own use a patented device in the US, does this mean I'm free to do so in New Zealand?

This thread is 10 days old, and has had over 2000 hits, I agree with Carl, the cat is out and the pigeons have flown, many times around the world, ZED's schema is certainly out there for all to see.

Is it correct that we only need to modify the intellectual property by 10% to void any claims litigation?

This is an exciting thread............

Cheers
Kev.

[Unregistered]

Breaking patents

Hi,
I wondering Bugwhiskers, and ZED, could it be that the discussion today about using a micro and changing the timings of the said schema, actually break it, is this why Minelab are so concerned? Or is it just Codan concerned over it's newly acquired assets.

I hope Carl this doesn't dampen the free spirit synonymous with this site.
I must register again too sorry!

Cheers
Kev.

[AzNuggetBob]

Is this 10% ? Just kidding.Its not a great mod but I can use all 4 channels on my 2100. Just tyed into the factory jumps and added two toggles.. But I can only run two channels at once. (so far) just havin fun.

[Aziz]

Personally, I was interested on the mystery of SD2000. As I saw the schematics and pulse timings, I decided to develop an own one, which definitly not work like the M/L's does.
I insure, I would not even to build this intellectual property for private nor for experimental purposes. In my opinion, it is not worth to build this project. We can develop even a better, easy and cheaper one.

On the other side, it is interesting to discuss about SD2000 for science purposes. So anyone can get an new idea of improvements and further developments.
;-)
Aziz

PS: The hole/window can propably be caused by the coil configuration. Has SD2000 more than two TX-coils?

[bugwhiskers]

Is this 10% ? Just kidding.Its not a great mod but I can use all 4 channels on my 2100. Just tyed into the factory jumps and added two toggles.. But I can only run two channels at once. (so far) just havin fun.

Hi AzNuggetBob,

Try running all 4 channels to a summing opamp. I have no idea why ML didn't do this with the 2 channels in the SD2000, only 1 channel (the strongest) ever gets through to the audio. Candy referred to the SD2000 as 2 detectors in 1, the problem is as it stands you only get the benefit of 1 at a time.

regards
bugwhiskers

[bugwhiskers]

Personally, I was interested on the mystery of SD2000. As I saw the schematics and pulse timings, I decided to develop an own one, which definitly not work like the M/L's does.
I insure, I would not even to build this intellectual property for private nor for experimental purposes. In my opinion, it is not worth to build this project. We can develop even a better, easy and cheaper one.

On the other side, it is interesting to discuss about SD2000 for science purposes. So anyone can get an new idea of improvements and further developments.
;-)
Aziz

PS: The hole/window can propably be caused by the coil configuration. Has SD2000 more than two TX-coils?

Hi Aziz,

Your coil software is magnificent, please continue with it.

As for the coils the SD2000 can use either a mono or a double D which has nothing to do with bust size.

regards
bugwhiskers