TESORO GOLDEN SABRE

[simonbaker]

Hi,
don't know why you have such poor results... but 15cm on a quater is really few stuff, device is much more sensitive.

Kind regards,
Max

Right now much noise because only prototype -- I hope to make it much better. I need to get a Euro coin to compare depth .

I have problem with iron -- can you explain? My tests show that discriminator circuit does not reject iron, because phase beyond silver. Instead Ground Balance pot is adjusted to reject iron. But if Ground Balance adjusted to reject iron, All-Metal mode cannot detect it either.

See my tests here: https://www.geotech1.com/thuntings/s...ad.php?t=14645

Regards,

-SB

[ivconic]

Hung Chang 3502 , made in Korea. Pretty good for my needs. 2x20MHz.
It is old model but this one is like brand new, almost never used. Works the same as it was made yesterday. Focus is excellent.
It is expensive here also. Yet i have seen few on e-bay for $400-500 and one even goes for $800 !
Simillar one in shop here costs arround 700e !!!! To much!
Other hand, one cahnnel's are cheap..usually 200e if new and less than 100e if used and old... Recently i got offer to buy obsolete one for 30e !? Ha,ha,ha!!!

Yes Max, now i remember! Huh, i forgot, thanks!

[ivconic]

Nice arrangement Driscoll !
Wise move to add audio mod on it. It will work much louder and smoother, i guarantee.
I will use this pcb in my next work..
Regards!

[rdec4]

ivconic, Max, simonbaker,

In what limit to 200 degrees change phase in your setup coil?

Should not be more than a few degrees and they should not have a significant impact on the depth, but only on discrimination and ground balance. They have to potentiometers for tuning.
Or wrong?

Why not set the correct phase of RC circuits, the output of the generator and the entrance to the receiver?

[Max]

ivconic, Max, simonbaker,

In what limit to 200 degrees change phase in your setup coil?

Should not be more than a few degrees and they should not have a significant impact on the depth, but only on discrimination and ground balance. They have to potentiometers for tuning.
Or wrong?

Why not set the correct phase of RC circuits, the output of the generator and the entrance to the receiver?

Hi,
that phase will not influence performance in air at all-metal: it influences your ability to get a good ground balance and a reliable discrimination.

So, if you are doing air tests in all-metal you'll not see anything wrong with also really different phase shift.

But when on soil... or when try to disc stuff you'll be surprised how bad it could be.

The critical adj is at coil... you null coil but search right phase also... so it's not trivial task and require enormous patience and a number of efforts to do it perfect.

I guess maybe at Tesoro as in other places they have a procedure to do that with few efforts... but usually you get average coils this way, at the end.

Sure not performative as the ones proposed here... but all factory made have excelent phase alignment to do geb and disc the right way: Tesoro is famous for reliable iron disc and discrimination stuff... not a case.

Kind regards,
Max

[rdec4]

Thanks for the response Max.

I'll ask.
Why not adjust the small phase difference in making individual coils from the electronics? There phase rotating block.

In the same work, the same number of turn and the same base for the coils and length: (), the difference in phase will be reset at very small.

I guess the difference in phase in individual coils is only a few degrees, which can be adjusted by the RC chains and set the range for regulating the discriminator and ground balance.

Regards,
rdec4

[Qiaozhi]

Hi Ivconic,
I posted that data: it's about 200° out of phase for original coils.

In the Qiaozhi's picture (of a 9x8'' coil) you see it very clear.

That's the phase, I got the same both on my 9x8'' and an 8'' round.

But still some problem exist on larger coils... expecially DD like.
Iron detection is better avoided in CC than DD... the flux shape is a problem for near iron, I noticed that even at right phase some large coils show that iron detection at overlap area when target is huge or too near the overlap.

Kind regards,
Max

Another method is to set the ground balance control to mid-position, and adjust the coils to achieve minimum voltage, while monitoring the output of the sample gate in the ground channel. This will automatically give you the correct phase shift between TX and RX. In this case, you only need a single-channel scope, or a meter.

[simonbaker]

Another method is to set the ground balance control to mid-position, and adjust the coils to achieve minimum voltage, while monitoring the output of the sample gate in the ground channel. This will automatically give you the correct phase shift between TX and RX. In this case, you only need a single-channel scope, or a meter.

Hi Qiaozhi, Max, Ivconic - can you explain how iron discrimination works with TGSL?

In my circuit, as I turn discrimination pot, discrimination order is:

foil, nickel, penny, dime/quarter, iron.

So I can't use discrim pot to knock out iron and keep others.

Instead, I turn Ground Balance until iron goes away. But then it is gone even for All-Metal mode.

I'm confused on this. How should it work?

Thanks,

-Sb

[simonbaker]

R40

Another question for the experts:

R40 100K is mysterious to me. It connects output of comparators U106 (after diode D12) back to non-inverting input of comparator U106b (ground bal channel).

It causes clipping of the comparators output to near ground (actually near the non-inverting input which is the output of LM308 ).

I see similar thing on Amigo II circuit. What is the purpose? Why clip to LM308 output instead just ground for example?

Regards,

-SB

[ivconic]

Another method is to set the ground balance control to mid-position, and adjust the coils to achieve minimum voltage, while monitoring the output of the sample gate in the ground channel. This will automatically give you the correct phase shift between TX and RX. In this case, you only need a single-channel scope, or a meter.

Ha,ha,ha! You are spying my work??? Perhaps you installed some bugs in my workshop??? Damn!
Not "another" but ONLY ONE, as showed so far with all TGS's i done.
Most accurate method to make and adjust optimal handmade coil is just what you described Quiaozhi! Not more truth with less words! What a benefit being born British!!! I wrote novels and novels ...and you beat me with just a few words. I agree 100%!
Ok folks, humor aside....Quiaozhi just explained exact method i am using on all my TGSL's.
Except scope part. I hadn't it and hadn't chance to fully observe gates.
Now i have it and observing would be much easier and more accurate.
Very important is to set GEB to middle position, so later you will have enough reserve on both sides.
GEB trimmer actually AFFECTS phase - remember that. But..if coil is nulled badly, aint no GEB trimmer to solve that.

[ivconic]

Hi Qiaozhi, Max, Ivconic - can you explain how iron discrimination works with TGSL?

In my circuit, as I turn discrimination pot, discrimination order is:

foil, nickel, penny, dime/quarter, iron.

So I can't use discrim pot to knock out iron and keep others.

Instead, I turn Ground Balance until iron goes away. But then it is gone even for All-Metal mode.

I'm confused on this. How should it work?

Thanks,

-Sb

"...Instead, I turn Ground Balance until iron goes away...."

Very wrong! You should turn GEB until ferrite rod goes ALMOST away - not iron. All this performed in ALL METAL mode.
Better than ferrite rod would be thing made from small pieces of rust, black sand, hot rock and very tiny and small pieces of ferrite, mixed up togather and formed in some 5x5cm shape...somebody already suggested and explained this at very first pages of this thread...search for it.
Than turn GEB untill that "thing" goes away...and at the same time switch to Disc mode (Disc pot to "1"), and try to detect small and thin silver coin. If it is detectable than leave that setup/preset that way...if not than loose GEB a bit just to start detection on thin silver and thin foil...and that is all!
Than switch back to All Metal mode and test again on ferrite mixture....If detection is appearing and it is strong than your coil is bad - make another one !

[ivconic]

Pretty "pictoresque" should be my next story. I will spit on some detectors here...but hey! That's life!
So story goes on...

This summer i had chance to fully test majority of cheaper metal detectors made in China. Except Black Knight, all others could be considered as object of one and the very same experience...so;

Coils are made in pretty well cosmetic manner. Looking nice and hi pro.
Yet all coils i have been seen are .....take a deep breath....without any Faraday Cage or simillar !!!???? Ha,ha,ha!!! What a spiiiit!
This HUGE drawback showed fully on real soil. Absolutelly unstabile and therefore unuseable totally in any descent work. Who ever told you different story, you may consider him as a fraud and liar!
So....next drawback is ..."machine" itself.
For example...MD3030 and MD3009 (not 3009a version) are sharing the very same "machine" inside.
Skim look on pcb gives FALSE impression that it is actually some Fisher project, pirated by pirates from China.
Ok...maybe those really intended to make real copy of Fisher...but they failed hardly!
Why?
Simply...many things very wrongly put togather there.
I have original 1266/65 8" coil in my workshop, so logically i connected it to both MD3030 and MD3009 and tested. The hell..working exactly the same as with original coil came with those toys.
I could NOT get any benefit using original, hi profile (f.cage included) coil made by Fisher!? What the hell? So it is not only about coil? What else? Of course machine itself...
What is the main drawback? (now i come to main point).
Same MD3030 and MD3009...with original coil and with Fisher coil...still can not remain silent on FERRITE ROD...while original 1265/66 is totally silent on same rod???
So....there are some trimmers inside MD3030 and 3009.
I assumed those ignorants didnt knew how to adjust those. So i adjusted and adjusted...and adjusted...and adjusted...and few days ago even used brand new scope....and all that without success!??
It is impossiblle to make it calm on ferrite rod, no matter what you do!?
No matter which mode..no matter pots positions...no matter trimm positions...always the same - screaming loud on ferrite rod...again and again..
So 2 days ago i used 5kg hammer and smashed 3009 pcb and with a huge pleasure toosed it through window of my workshop! What a pleasure! I can not describe here!

To make this simplier....very simple conclusion;
if achived to be calm on ferrite rod...later that detector is very calm and stabille on real soil...and if not than that detector is a crap,trash and should be hammered asap!
As explained...at first i suspected mostly unshielded coils...but later turned that both (coil and detector) are totally mismatched and presents HUGE vaste of money.
Only exception is Black Knight...very stabille, very calm and with so so detection and disc. But comparing with other trash came from China...Black Knight is a real "bijou".



P.S.
Reffering remark on MD3009 and MD3009a - those are totally different. MD3009a is coming in Europe as Seben, and it is non motion...yet totall crap and totally unuseable trash. What really confused me is simillar label on pcb's although those are totally different???



This stroy i told just to picture you why ferrite rod is usefull in many cases...especially in process of nulling coils and adjusting machine.

MD3030 and MD3009 senced and loud detected every grass, stone and wet on soil, on real terrain, outdoor. I spent hours trying to make those work so so calm and stabille - without success.

Only way to make those stabille is to reduce Sense to level where it is able do detect 1cm coin bairly at 3-5cm depth!!! Ha,ha,ha,ha,ha!!!!
What a trash! What a fraud!


Oh...i can only imagine those machines to be so so succesfully used only on plain sand...on beaches or in some desert..and nowhere else.


A bit off topic here...but recently i tested also 2 branded machines; XP Gold Max (18kHz) and Cscope 2MX...
XP is so good and pleasant to work with - i dont have words!!! It is shame i can not afford to have it yet... need some money savings ...shame! Very deep, precise and accurate...real sweet machine. Justify every penny payed for it! If it was 1000e even than would be worth of those money.
Probably one of the best on market today!

Other hand Cscope 2MX is modest, middle class machine...yet very good, accurate and stabille! Bravo for Cscope! Also worth every penny involved! Probably the best compromise between price and performances today. Very simple yet very accurate, stabille and with very descent depths. Bravo Cscope! And Hurrrahh for XP !!!

As very old Cscope fan, i would like to have chance to see and test CS990 XD and CS3MX. Those models are "eaching" my imagination strongly!
I sense old Cscope spirit in those two models...although not sure yet...
Huh...damn money! Always missing!

[ivconic]

It would be a shame to waste so so descent enclosure from MD3009...so i decided to use it and put another TGSL inside. Logically i had to respect original 3009 pcb dimensions and shape to suit enlosure. What a hard labour!?
So before scraped it and enjoyed with hammer, first i cleaned pcb form any component and scanned it in 1:1 so later i could import it in Sprint Layout and draw TGSL on it...Ha,ha,ha,ha!!! What a lunatic am i?
Anybody more crazy than me here? Seriously i have doubts!

[ivconic]

Oh i forgot; only one error on this pcb!
Look that wrong connection at emiter resistor - should go to +8V not to ground and other from base to gnd not to +8V...
Everything else seems to be good...
Working in progress...will be ready tomorrow..

[amtech2005]

TESORO GOLDEN SABRE

Hello Ivconic , I am looking forward to the new sprint lay-out and we will see if it matches this photo ???? Thank-You..............Eugene