field test unit no 001 "model T"

[Mechanic]

Grouse! With 2.5uS damping you should be able to pick up smaller targets even with a large coil. Eager to see how you go with the field test....

Cheers Mick

[sido]

...good news everybody .... I have thrown the discrete Earth Field filter out of the circuit and using a "tricksy" variation of the same technique that achieves fast damping and autoground balance the EF problem is now resolved .... field test results soon. This was the last hurdle on the front end .. the presence of the Earth Field filter caused some reduction in sensitivity.
Transmit coil voltage is now set at 6 volts with 1.6 amp peak current and pulse repitition of 5 Khz and 2.5 us damping on the excellent "Nuggetfinder" Coil. There are no target holes and no EMI issues.

Wow, that is some unique specs. Wish your field testing a success
Did i tell ya i do field testing for free Only joking, good luck there Moodz.
If performance in the field matches the units specs, you have a winner there.

Cheers Sid

[ZED]

Nice one Moodz now stop futzing around and start selling your product.

Zed

[dougAEGPF]

Nice one Moodz now stop futzing around and start selling your product.

Zed

Agreed! Another independent MD developer that was omitted from Vbeeeks post.
But will Moodz be allowed to sell?
dougAEGPF

[Aziz]

Wow! Hard times coming up to the competitors and big players...

Where would we be without the forum trolls, who encouraged us breaking the walls and limits?
Anyway.

Good job Moodz.

Cheers,
Aziz

[vbeeeks]

Agreed! Another independent MD developer that was omitted from Vbeeeks post.
But will Moodz be allowed to sell?
dougAEGPF

I will not comment here anything from my past threads - suffice to say that I intentionally left the list incomplete, I knew something but also don't know many things about what I uttered there.... lest I become a pariah and desecrate this thread - period.

Moodz as to my shortcomings, would you suggest the link is good enough to understand many things about detectors
http://www.dtic.mil/cgi-bin/GetTRDoc?AD=ADA509654, i.e if you follow the same philosophy behind the scenes, I may be able to follow the maths involved.

[moodz]

I will not comment here anything from my past threads - suffice to say that I intentionally left the list incomplete, I knew something but also don't know many things about what I uttered there.... lest I become a pariah and desecrate this thread - period.

Moodz as to my shortcomings, would you suggest the link is good enough to understand many things about detectors
http://www.dtic.mil/cgi-bin/GetTRDoc?AD=ADA509654, i.e if you follow the same philosophy behind the scenes, I may be able to follow the maths involved.

That is quite a document ..... not sure I would recommend it as a beginners guide to the art however if you can follow the math .....it seems to fairly comprehensive .... I am not sure that it will translate well into a practical circuit.

[moodz]

...good news everybody .... I have thrown the discrete Earth Field filter out of the circuit and using a "tricksy" variation of the same technique that achieves fast damping and autoground balance the EF problem is now resolved .... field test results soon. This was the last hurdle on the front end .. the presence of the Earth Field filter caused some reduction in sensitivity.
Transmit coil voltage is now set at 6 volts with 1.6 amp peak current and pulse repitition of 5 Khz and 2.5 us damping on the excellent "Nuggetfinder" Coil. There are no target holes and no EMI issues.

Just when you think you are there .... bugga .... forgot about the discrim functionality. I will have to revisit that on the bench again ( lots of measurements ... sigh ).
However the pre-testing of the EF cancellation indicate that not only does this innovation cancel EF but also all non synchronous noise below the TX frequency. Mains hum, burst and repetitive .... and low frequency amplifier noise ...... Happily the core signal block remained unchanged so the provisional patents covering auto damping, fast damping, ground balancing, noise rejection etc etc will not require rewriting ... the bit that adds EF will have to be written up as there is no prior art that I can see ! ( actually cant believe it works as well as it does ... field tests will tell all )

Thanks for all your supportive comments guys. Will keep you informed.


Pinback: Er, Talby, he's drifting away from the ship without his jetpack.
Boiler: Can you dig that? I always knew that guy was weird.
"DarkStar" 1974

[Aziz]

Sounds like we need UFox again saying: "No, you can't do that!"

If someone could solve the issue, then you Moodz!
Aziz

[vbeeeks]

MOS - Moodz Operating System

That is quite a document ..... not sure I would recommend it as a beginners guide to the art however if you can follow the math .....it seems to fairly comprehensive .... I am not sure that it will translate well into a practical circuit.

I know but some constants are thumb-rule & magical and proven beyond doubt and much consistent with what the forum guru's are discussing - you also showed one jar of that hot soil powder to Aziz - the empirical constants and state boundaries are what is used in your math that defines the practical electronic parameters of pulse shaping and switching isn't it? I am learning - only slowly TDEM & FDEM co-relation - in layman terms my action and the reaction in response to my action. Okay you all are light years ahead and have practically implemented much of what I am reading now - small steps!!! Somewhere I see you coding a metal detecting Operating System. Will it be open-source?

[moodz]

I have already put up the source code for the UNIPI ... happy to work more on it. Try Carl's book .... it looks like a good investment.

moodz

[moodz]

Sounds like we need UFox again saying: "No, you can't do that!"

If someone could solve the issue, then you Moodz!
Aziz

The performance is excellent .... been doing some optimising of the Earth Field / Hum removal on the front end gain block.



Pic below shows pulse train with severe 1 volt peak 50 hz hum superimposed. After passing through the EF removal prototype gain block ( its not your average amplifier LOL ) I get the pulse train with no hum ... actually if you look very carefully there is some residual ... however the pulse train has been gained up ... the hum has been severely attenuated/removed ..... The green trace is the input ... the blue trace is the output ..... there are some DC offsets ... cant have everything.... its all DC coupled and not a capacitor or inductor in the circuit ( or diode for ppl thinking this is some sort of clamp cct )

UF .. you can have your capacitor back now.

moodz

[KahlesMilcon]

Moodz,
I would stop posting until you get the paperwork worked out, patents, copyrights etc in the US and AZ.
Especially the copyrights for the code and the layout.

Just saying.
Good luck and best wishes.

Milcon

[Carl-NC]

Copyrights on code & layouts are often automatic (in the US, at least), and pretty worthless. Patents are worth as much as your bank account, which is better than nothing.

[dougAEGPF]

Copyrights on code & layouts are often automatic (in the US, at least), and pretty worthless. Patents are worth as much as your bank account, which is better than nothing.

If you don't have a big bank account then what is the solution?Go underground, open source with the whole thing or sell the whole thing to a big detector company or someone with a lot of money to burn?
dougAEGPF