TESORO GOLDEN SABRE

[Fred]

-Tiktak,
You connect the - of your multimeter to the - of the battery,and the + to pin 7 of lf 353.you will never get 0V , but try to go as low as possible.

-Thanks, Nelson!

Regards,
Fred.

[erolunall]

part list tesero golden sabre

Part List golden sabre
IC
5xLM393
3xLM358
2x LM308N
LF353
CD4024
TL062
CAPASİTÖR
100n
5x220mf
9x22nf
7x220nf
4x470nf
4x100pf
4x4,7mf bipolar
15pf
68pf
10mf tantalyum
2x5pf
15nf
diyot
10x1n4148
4v7 zener
resistor
7x47k
7x1m
5x1k
2x330k
150 ohm
2x27k
12x100k
22ohm
4x24k
3x220k
4x2k2
200k
4x20k
2x10 k
3x15k
3x470k
6x4k7
2x5k1
3k9
transistor
7808 TRANSİSTOR
2x2N2907
2x2N2222
6XBF245C
MPSA13 OR BC517
3X100K POTANSİYOMETER & 2x10k potansiyometer

[tiktak]

Hi

Hello Tiktak,

I am sure any voltmeter will do the job, you just have to put it in AC at the output of lf353 (pin 7) and you will find that the best nulling is very dificult to find,no dead spot at all!
and you will never get 0v if everything is normal...
Good luck,
Fred

Hi,
Thanks.
I will try!But because I am newbie where should I conect -?
+to LF353 pin 7.As I say I have only cheap,but I think its not too bad multimeter.

[tiktak]

Hi

Hi,
I use scope ... but any good AC millivoltemeter will do the job. Also Fred is right... you can measure at pin7 of LF353 for minimum voltage saving you the work of making yourself amplifier/millivoltmeter circuit.

It's your choice.

Best regards,
Max

Hi,
Max.
I have multimeter!So I have to put it again in AC 200mV and conect + to LF353 pin7 ?But where to conect -?And look again for 0.00?
I have just finish 12 OO coil like yours and will test soon,but wanna make and 255X137 like Ivconic's and test both on same field!I have already wind one but on 255X137 former and will null,seal and test it too because it is already made and shielded.
The thing that borders me is that now I remember that before one week I have made a short when trying to measure the voltage of the battery/I measure the V on bux where battery is conecting/i haven't noticed any diferances in behaviour,but please tell me can this happen?I mean can this short go without burned elements or I must be shore that something is burned?
Thanks

[nelson]

Hi Fred and congratulations for been another friend who tried TGS.
These days a havent to much time to experiment with new coils, to get more deep detection, but for shure TGS have a lot of thinks to show us.
Keep going and post your expirencies here.

Best regards
Nelson

Hi,
Here i post some pics of my TGS : i hope they can be usefull .The coil form is from a CRT monitor support, excellent as very strong, but a bit too small: diameter of the coil is only 22cm.With this coil i could get 25cm for 1 euro coin,same foir similar size of gold, and around 30cm for a big copper coin.
I will try to improve it a little and build a bigger coils, will post eventals (good) results
Happy building,
Fred.

[Darko]

Here is my work of Vladimir's PCB. Sorry for low quality of pic.

[Darko]

How can I post pictures here? I dont know how. Please help.

[Max]

Hi all,
I cannot make at now double sided photo-process (cause I haven't suitable good material to do it)... so thinking at Vladimir's pcb design I've made some small correction to the original picture file...

I haven't made any board cause of small time... but I'll do soon I think.


I've cleaned some tracks and kinda of dirt (colors) from original file to better suit photo-process.

So... maybe that file could be useful to others too... then I post it here.

Kind regards,
Max

[Darko]

Hi Darko,

The housing is form an old comercial Italian radio system, really it is the right size,i just had to file a litle the sides. The problem is weight,it is extruded aluminium.I dont like very much the front panel i have made, i may change it .I am also waiting for some wire to make more coils experiments.
did you made your front panel from some software? looks really good.
Happy building,
regards,
Fred.

To draw a front panel and complete box I use SprintLayout5. If you like I can send to your mail drawing of front panel I made, which should be suitable for your housing of TGS. Maybe you need only to resize drawing a bit because dimensions of your housing. I think you reach very good performance with your DD22 coil and with DD28 your TGS will rocks. I also ordered some wire for my new DD28 coil, but I think that a 0,275 diameter wire is bit a better for this size of coil. And I agree with you that is nulling of coil with round centre is quite easiest than with flat sides of D shapes.

Regards,
Darko

[Fred]

Hi Darko,

The housing is form an old comercial Italian radio system, really it is the right size,i just had to file a litle the sides. The problem is weight,it is extruded aluminium.I dont like very much the front panel i have made, i may change it .I am also waiting for some wire to make more coils experiments.
did you made your front panel from some software? looks really good.
Happy building,
regards,
Fred.

[Darko]

Darko,
Even if i would have used diferent words, i think Ivconic is right here, dont give up ,to build the coil and achieve good results is not THAT dificult .
And listen to dad he has good advices.
Regards,
Fred.

And Fred, thank you for yuor advices. And thank you for pictures of yuor TGS. Yuor TGS looks great. About housing. What kind of box it is? Looks wery nice and practical to pack TGS into. I have my own design look likes in my Avatar. It's not poor but require quite time for making one and because of that I looking for already maded box which will be good for TGS.

Best regards,
Darko

[Darko]

Darko,
Even if i would have used diferent words, i think Ivconic is right here, dont give up ,to build the coil and achieve good results is not THAT dificult .
And listen to dad he has good advices.
Regards,
Fred.

Actually I already achieved good performance with my TGS before I burn it. Thank you. Now machine again works like before - thanks to Max and his advices to me. And please, give my regards to dad.
Regards

[Darko]

Zemljak! ....

Ha, ha, ha, gresis sine,ali gresis silno sine. Sa nekim si me pomesao.

I think you mix me up with someone. But it is not mirracle here, because here is many people which need a help and you is just one single person and can't help everyone.

[Darko]

Hi,
if sens pot have no effect on your TGS there is some mistake... maybe in coil. When things are right it gives maximum sens at max position but when at minimum you can always detect stuff but at lower range. I think that is a regulation say from 70% to 100% of total...so just on 30% of sens regulation starting about from 70.

But that may change from one homemade to another cause of tollerances of components... and coils.

If coil is no good or you have problems at preamp and the like I think you couldn't notice that behaviour cause maybe your detector sound when signal is already strong (near target)... then you are already under 70% of theoric range... thus giving no variations.

If it isn't coil:
you have to check the signal path... if preamp is ok you'll focus on fets and then 308s (or other ics there)... and then on comparators after the sens pot.

All parts can give that problem if there is a mistake or wrong stuff/values: an example are fets ... you can use different kind even various versions of the same device like BF245A,B or C but there are differences about cutoff voltages... then your devices could work bad if not compatible with TGS sampling voltages commands at gates.

The original fet TIS75 has e.g. min VGSoff -0.8V and max -4V ; but the BF245 has min -0.5 to max -8V that's a huge difference.

If you consider the worse case you need really -8V to switch off them then you'll get into troubles cause maximum negative voltage for TGS is -6.2V and command line of fets don't reach that value but something less around -6V.

So... your fets, in the worse case, could remain partially closed... that's why is so important having a scope in that measures: you can see if e.g. sampler part works ok or not. For other parts is the same... looking at signals is much more efficient way of finding mistakes in circuits.

Best regards,
Max

Hi Max,

Thanks to your help and advices problem solved. It's a bad FET's. Now TGS works just as before burned. Thank you for help.

Regards,
Darko

[Fred]

Darko,
Even if i would have used diferent words, i think Ivconic is right here, dont give up ,to build the coil and achieve good results is not THAT dificult .
And listen to dad he has good advices.
Regards,
Fred.