Cobra II

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One feature of the ST was the LM3578 switching regulator. Now we can see a landscape of similarities between all the designs of that era. This was quite a small circle of people, Id say less than 15 individuals leading the way in this niche.

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LM3578
lm3578a.pdf

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Check out this tone arrangement here, pretty slick.

And to think that Payne also wrote his own code for the treasure baron series and others, that's pretty impressive. I wonder what became of the original code. It must archived somewhere.

[Altra]

Check out this tone arrangement here, pretty slick.

And to think that Payne also wrote his own code for the treasure baron series and others, that's pretty impressive. I wonder what became of the original code. It must archived somewhere.

Most of those detectors were straight cmos logic chips, no micro-processors. I think the auto tracking ground balance module did have a processor, but never have seen a schematic. Have you figured out what the 3hz clock is doing? Maybe something to maintain the analog ground?

Add:I found this text I copied from one the old forums

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3Hz I think is for low battery "beep beep beep". The LM2951 voltage regulator chip has an error pin that can be set when input voltage(battery) is low. The output high is then modulated at 3Hz and mixed(modulate) (195Hz) via a comparator through to the audio amp. I hope I got it right, otherwise somebody can explain what's goin on.
LM2951.pdf

[Altra]

I didn't realize the error pin was an output. So low battery trigger makes sense.

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from the manual:
Control Box
The Treasure Baron needs 8 AA's in a separate pack to drive
the Deep Hunter Module for truly more power. With use of the Deep Hunter
Module you can use an "on board" charging system when you are using Nicad
rechargeable batteries. A recharge takes about 4-1/2 hours. The condition of the
batteries can be checked using the LED lights (more on this later) plus the audio
gives a chirping or pulsing sound when batteries are low.

[ivconic]

Dealing with Cobra II is a very good idea.
There is enormous potential in that project. I kept this as a "secret" for years.
And now I'm not sure if it's ethical and moral to talk about the details.
For the reason that I got some vital information from our friend Nupi from this forum, who did a fantastic job.
But he hasn't been in touch for some time... I don't know what's going on with him, he complained to me about some health problems.
And he didn't give me permission to present the data to the public.
And his work was continued by his son. Not sure if he is a member of the forum.
For those reasons, I can't directly give anything here.
But I'll just say that reworking the Cobra II is a phenomenal idea and that if you're persistent enough; you will get similar results as Nupi.

[ivconic]

I'll add a little help. Why this is a phenomenal choice.
The results I saw that Nupi achieved, in terms of "recovery speed (reactivity)" are such that I fell off my chair!
Deus 1 and 2 are "peanuts" compared to the Nupi's detector in this feature.
And the other day I was watching the CTX3030 and the Manticore in similar tests.
Although those are fantastic machines; those are very far below what I saw in a couple of demo videos sent to me by Nupi.

[ivconic]

I'll add one more hint.
The Bulgarian Vista Smart detector ... unjustifiably neglected by the public ... has a lot in common with the Cobra II.
And it's also easy to modify it to the level of Nupi's detector.
And finally here is a link to Nupi's channel where some of the demos are posted.
Carefully watch each clip slowly.
This is not advertising nonsense.
It is a real set of tests with real results.

https://www.youtube.com/@m.d.prototypesexperiments9493

[ivconic]

Probably the first, only and last VLF I/B that easily beats the crap out of top notch ML PI...

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Thanks for the info, I've been taking a very close look at all of George Payne's schematics and patents that I could find.