TESORO GOLDEN SABRE

[tiktak]

Hi

Hi,
Ivconic I can't understand how you digg 254 coins when this detector can't recognize half of rusty horse shoe?
Unles my pcb have this behaviour!!
Some large Irons are discriminated,but this half of rusty horseshoe is making my TGS singing like on coin!

Did you wind TX and RX in same direction or in oposite?
Thanks

[ApBerg]

LF353-1

Hello Ivica.

Made a testboard, giving me also some problems. If I pas my hand over the print it wil give an echo..... can be becorse of the long connections.?!
Can also be a problem in the desing from the print.......?!
If I pul out the zener 4v3 I got the same signal at 353-1 that you have, look at the screenshot.The transmitsignal has so also some effect.

The first board is working fine, it is the test board that gives problems, wel wil check and test tings, if answers are there I let you know.

Ap

[Geo]

Hi. I traced the signal at pin1 of LF353 and it is a perfect sinus signal. No square and without any anomalies. But when i put the sens at max (>7) "at manual mode" i have a lot of erratic signals ( i connected the 1M resistor). At disc mode that i disconnect the resistor i can work with full?? sens(9...9.5/10).
Generally at disc mode it is more stable but i think that it dont work good. So when i put the pot right then don't detect any coin but the same for the soldering cream can that it is from iron. I will try it more.....
About Notch........ I can't understand if it works and what it do.
Regards

[Geo]

I can't find where it is the cable to connect the mobile phone to pc so to upload the photos from oscilloscope. If i will find it i will uload the photos

[porkluvr]

"...I think that you probably have some other and bigger problem that mask the positive effects of having it.

That's why you cannot see advantages... or maybe is just simulator that make us crazy now..."

Most likely i do!

But also possible other??? I never liked simulators...many times results from them do not correlate with reality!!! Plain truth!

Confucious say:
You can lead a horse to water, BUT, you can't make him drink.
i give up.

[Geo]

I found the cable


Yes i found the cable so i attach here the "signal at pin1 of LF353 " at my scope.

[ivconic]

Hi,

Ivconic I can't understand how you digg 254 coins when this detector can't recognize half of rusty horse shoe?
Unles my pcb have this behaviour!!
Some large Irons are discriminated,but this half of rusty horseshoe is making my TGS singing like on coin!

Did you wind TX and RX in same direction or in oposite?
Thanks

Hah,hah,hah!!!
What kind of question is that? How i dug those coins..!?!?!? Simply, i detected those and dug them, one by one...Simply as that.
TikTak you are, almost always, asking me simillar questions..? Why?
Like you "investigating something in my posts"? Are you Serbian? Bet you are!
Are you, by some strange coincidence Darko? Bet you are! Or one of his friends!? If you want something to say here, dont hesitate...c'mon spell it!
But please do not ask me questions like that anymore....
"Half of rusty horse shoe..."!? Is it possible that there are some terrains without horse shoes "installed" in??
How i couldnt detect horse shoe? Simply, there wasnt anyone there, where i went to propsect... Even if were, my Dscrimination circuitry works very well, also my coils are nulled perfectly, so there is NOTICEABLE DIFFERENCE BETWEEN sound produced by horse shoe and coin!

Anyway, i am glad to see that you finally made coil with detection over 30cm...Bravo! Good job!

[ivconic]

Confucious say:
You can lead a horse to water, BUT, you can't make him drink.
i give up.

Eeeeeahh heeeeaaaah pffffffff!

Hah,hah,hah...! Porkluvr i liked your post!!

[ivconic]

ApBerg,Geo...it is strange? I replaced LF353 with; TL082,TL072,TL062,TLC272.....Every one gave me same oscigramm at pin 1. Same as i posted above??? It is not about LF353.
Come to suspect either to osciloscope either to method i am scoping pin 1.
Read this: gnd probe i do connect on gnd or -pole of accu, signal probe i put on pin 1. ...isnt that right?
So aleays i gain same oscigramm....and TGSL is working rally PERFECT. No difference between LF353 and TL082...2cm coin detect at 36cm in the air. No false signals,beeps, chatters - nothing. Stabile as stone. Same in All Metal mode, very stabile! I dont use 1M any more. Yes sound is weak, but as TikTak stated; you can always use headphones...until we make some audio mod...
And one more thing: i am usin 8 ohms speaker WITHOUT extra resistance any more! Now i have more elegant solution which affects overall performances in positive way; instead that 2K2 at last LM358 (on some schematics noted as 33K) i put 10K. Why? Simplyi founded it by experiment. Actually 8K2 is suited more but i took 10k...to have some reserve in audio on more mineralized terrains...If you interested play with it. You will see yourself.

One more thing; i think my oscilogramm (i posted here) is most accurate and that is the way it should be. To understand this you have to scope pin 2. of LM393 - input from Disc stage. You have to see and follow signal behavior from point where Disc is lowest to point where Disc is highest - adjusting Disc pot from minimum to maximum while scoping pin 2.
If you want to see my results, take a look at this video:

[ivconic]

Final notes

I reac the point where can say that i am very satisfied with TGSL, after a lot of effort involved and lot of problems so i'll rather make final conclusion and stop thinking about this anymore. Further i'll take a part in this discussion only when some new mod occurs....

Conclusion:

TGSL is working PERFECT in All Metal and DISC mode. Neither one false signal even if i swing, bend or anyhow "torture" cable and coil.
I am not using 1M resistor any more. I am not using any extra resistances in serie with speaker any more, cose i changed resistor 2K2 (33K) with 10 K resistor. Although lowest resistance i can suggest here is 8K2...Experiment and you will see. I can freely lift Sense pot to "9" at All Metal mode or "10" to Disc mode without chance to face any false signal at all.
In Disc mode when Disc pot. is at minimum - "0" it is still stabile and calm. Discrimination is perfect...
Only thing that bug me is weak audio but this has nothing to do with present setup. It will need some mod to have louder tone.
At front end i put again LF353 just to respect original setup, but aint no difference if i put TL082 too. Works same.

- 2cm coin at 40cm in the air (AllMetal) and 37cn in Disc mode..
- Cola can at 85cm in the air (AllMetal) and 80cm in Disc mode...
Stabile,stabile,stabile...all i ever wanted from detector..
At the end it showed that oscillogramms i posted here (latest one)are accurate-no mistakes at all...

That is all from me.
Next thing i am interested would be audio mod....but now i'll take rest for few days...
Regards!

[Qiaozhi]

"...I think that you probably have some other and bigger problem that mask the positive effects of having it.

That's why you cannot see advantages... or maybe is just simulator that make us crazy now..."

Most likely i do!

But also possible other??? I never liked simulators...many times results from them do not correlate with reality!!! Plain truth!

This depends on how proficient you are with a SPICE simulator. As with any computer program - "rubbish in, rubbish out".

[Geo]

Hello Ivica.

Made a testboard, giving me also some problems. If I pas my hand over the print it wil give an echo..... can be becorse of the long connections.?!
Can also be a problem in the desing from the print.......?!
If I pul out the zener 4v3 I got the same signal at 353-1 that you have, look at the screenshot.The transmitsignal has so also some effect.

The first board is working fine, it is the test board that gives problems, wel wil check and test tings, if answers are there I let you know.

Ap

Hi Ap. I have a problem like your........
Sometimes when i touch the pcb or the coil housing or any wire i have erratic signals (beep...beep...etc). Other times it works ok. I think that it must be shielding problem. If i will find it i"ll write you. I must go out to test it (when rain stops) because i am afraid that at my Lab there are a lot of parasitic signals.
When the box with the pcb is at a position with the potentiometers to look the roof then i can put the sens to "7"position". But if i rotate the box with pcb 90degrees then i can put the sens at maximun.
What to say???
Regards

[Geo]

For Ivica and Max.
Do you tried to connect the Rx capacitor (15nf) at the wind of coil before the cable (from coil to detector)
Regards

[Geo]

Hi Geo,
fine. If you tune coil and it's 32cm diameter you'll get more depth I think.

As you can see the TGS circuit is good for depth with small things... much like some PI detectors with small coils!

My only thoughts are about sensitivity to very small objects like 1eur-cent sized things... maybe the 32cm coil would detect them at lower distance cause of field shape/density.

Let me know.

Kind regards,
Max

Hi Max. I have not a 1Euro-cent to try, so i found at my Lab a old bronze coin (unknown) 7mm diameter (yes it is very small). I detect it at 20...22cm. I don't say you for sure 22 or 20 cm because at full sens as i wrote before i have some parasitic signals.
Regards

[Max]

Hi all,
early this morning I've made all the stuff... test-points map and pictures... very hard work cause I had to dismantle board... and I need in next few days... so now I have to reassemble again...

anyway, here we are ! A full set of traced signals from TGS.

I still have the problem at LF353... but cause Geo and Ap haven't in some of their measures I strongly suspect problem is related to my LF353 cause came from an old stock of parts, thought it's new and never used before.

You can see that problem occourrs just on pin2 of 353... where are dumped oscillations you can see clear in one picture.

I hope that's enough... cause otherwise I have to dismantle again and that's not so funny!

In the map you can see where test-points are an index for each signals, in the list you can see explaination of figures and references to measured signals.

Kind regards,
Max