TESORO GOLDEN SABRE

[waltr]

hi friends!
I made tgsl with two coils(10" and 6")
both coils do not sens more than 18cm for coins!
very low!!

i nulled coil with multimeter on lowest possible value!!
All metal/disc part does not work!!

What do the signals to the FET Gates look like on an O'scope????
Do they look like the scope pictures in the TGSL101.pdf???

What does the RX signal compared to the TX signal phase look like on a O'scope?

What Coins??? The 'standard' is a 1 Euro coin and maximum distance anyone has gotten in about 30cm with that large coin. Smaller coin detect at much less distance.

How well did the GB adjust work?

There is an entire TGSL forum topic in the "projects" group. Reading there will be helpful to you.
https://www.geotech1.com/forums/foru...e-Bandido-TGSL

Be sure to down load the TGSL101.pdf document. Then check your circuit against the scope pictures.

[mostafalesnar91]

okay,how should I do this?
Impossible with a Multimeter??
parallezing a capacitor with rx to helps increase the depth??

[mostafalesnar91]

What do the signals to the FET Gates look like on an O'scope????
Do they look like the scope pictures in the TGSL101.pdf???

What does the RX signal compared to the TX signal phase look like on a O'scope?

What Coins??? The 'standard' is a 1 Euro coin and maximum distance anyone has gotten in about 30cm with that large coin. Smaller coin detect at much less distance.

How well did the GB adjust work?

There is an entire TGSL forum topic in the "projects" group. Reading there will be helpful to you.
https://www.geotech1.com/forums/foru...e-Bandido-TGSL

Be sure to down load the TGSL101.pdf document. Then check your circuit against the scope pictures.

thanks,but my scope not working at this time!!
otherwise,I would have completed this project very easily!!
I'm iranian and 1 eu is very expensive here!!!
I tested other 25 mm coins!
I don't know how to ground balance!!

[waltr]

thanks,but my scope not working at this time!!
otherwise,I would have completed this project very easily!!
I'm iranian and 1 eu is very expensive here!!!
I tested other 25 mm coins!
I don't know how to ground balance!!

Sorry your scope is not working but it is needed to properly setup TGSL and for troubleshooting. Try to either get your scope working or borrow one that does work.
I also do not have a 1 euro coin so can not directly compare to distance others get. Another 25mm coin will work well enough.

If the TGSL Circuits are working properly and detection distance in low then the issue is probably the coil. The coil build and nulling is the trickiest part of this build. A scope is needed to properly build the coil. First step is insuring each coil (RX & TX) oscillate at the correct difference. Then looking at the Phase difference between TX & RX signals.
Adding caps to RX or TX circuits may need to be done to obtain the proper Phase difference when coils are Nulled.

https://www.geotech1.com/forums/show...mplete-Details
Is where all the documents for building and adjusting is located. The TGSL_101 must be read and has the GB adjustment procedure.
Read the TGSL threads and keep working on it.

[kt315]

take small piece of ferrite. but not in hand, glue it on wood lath.
move the lath above coil. hear reaction in all-metal mode. you do not have hear nothing.
it is balanced point on ground, certainly approx point.

[mostafalesnar91]

take small piece of ferrite. but not in hand, glue it on wood lath.
move the lath above coil. hear reaction in all-metal mode. you do not have hear nothing.
it is balanced point on ground, certainly approx point.

Thanks my old friend!!
I did it correctly and set the device to a state that does not sens ferrite!!
There is another issue!
Iron is sensed in both allmetal/disk!!

[mostafalesnar91]

take small piece of ferrite. but not in hand, glue it on wood lath.
move the lath above coil. hear reaction in all-metal mode. you do not have hear nothing.
it is balanced point on ground, certainly approx point.

Thanks my old friend!!
I did it correctly and set the device to a state that does not sens ferrite!!so GB is okay!
There is another issue!
Iron is sensed in both allmetal/disk!!

[mostafalesnar91]

friends who have balanced the coil with a scope!
They may check with a multimeter what number Rx shows in AC mode?

[kt315]

i grasp you closed foil rx tx shields together in crossing points. the typical mistake.

[mostafalesnar91]

i grasp you closed foil rx tx shields together in crossing points. the typical mistake.

a genius is someone who succeeds in this way

[kt315]

had catch up you now for the nose! ))) i was right buddy.

[mostafalesnar91]

About nulling - balancing coils;

So far i made a lot of coils...Also experimented a lot...
Max can you repeat me your final measurements when your coil is nulled?
First is good to know that aint no multimeter with which we can accuratelly measure induced voltage on RX coil. Yes we can have some approx. results but not quite accurate...Why? Most of multimeters have good response on low frequencies, but on higher not! Error level rises up as frequency rising.
That's why oscilloscope is unreplaceable in accurate measurements..
But....in case we dont have osci.- must use what we have..Simply as that.
I do have quite useable multimeter with 200mV range AC/DC...So when finishing nullling coil i usually gain 0.000 mV...On first glance this sounds like a perfect balanced coil! But, as we know from experience...it is almost imposiblle to absolute balnce coils, due many objective reasons.
Above mentioned nulling is measured without 15nF parallel to RX coil. When i add that capacitor, induced voltage rises up to 0.009mv in most of cases. In few cases it raised up to 0.012mV...Than i triead again to fine readjust null to obtain absolute zero...yet without succes...Quite expectable.
But, somethimes i am to lunatic about those things...i want to push more and more, so today i made experiment with one coil. I nulled it with attached capacitor 15nF parallel to RX. Final voltage was 0.008mV...
I figured way how to achieve absolute zero; i put (carefully chosen) few very small pieces of Al foil inside coil housing, covering few spots on coils.Must mention those pieces are not connected anyhow in coil setup. Those pieces actually play role of "foreign body" inside coil. By moving them slowly,carefully inside coil i found exact spots and gained absolute zero balnced coils!!!
Actaully those Al pieces provoked minor induction, enough just to balance coil to zero.Coil is finished., filled with mass.Drained...and now is ready for terrain work. I checked it with detector.....PERFECT!!!! I gained extra 2cm's on single coin!!! Stabillity is good as it was before. Discrimination also good...
What to say? Crazy experiment gave me crazy result!!
Now i am thinking other thing; so i put Al pieces - "coloured" metal...What should be if i put iron pieces ("non-coloured") instead Al???
Only way to find out is to make another coil and try. I am planing to do that tomorrow...
I do know what is all about....perfectly clear to me. But i would like to hear your opinions...?
Heh,heh,heh...!

P.S.
You should appreciate this! I gave up one of "master secret" here!

So,you say this method of ivconic is mistake!!!!

[mostafalesnar91]

Ivconic is not here

About nulling - balancing coils;

So far i made a lot of coils...Also experimented a lot...
Max can you repeat me your final measurements when your coil is nulled?
First is good to know that aint no multimeter with which we can accuratelly measure induced voltage on RX coil. Yes we can have some approx. results but not quite accurate...Why? Most of multimeters have good response on low frequencies, but on higher not! Error level rises up as frequency rising.
That's why oscilloscope is unreplaceable in accurate measurements..
But....in case we dont have osci.- must use what we have..Simply as that.
I do have quite useable multimeter with 200mV range AC/DC...So when finishing nullling coil i usually gain 0.000 mV...On first glance this sounds like a perfect balanced coil! But, as we know from experience...it is almost imposiblle to absolute balnce coils, due many objective reasons.
Above mentioned nulling is measured without 15nF parallel to RX coil. When i add that capacitor, induced voltage rises up to 0.009mv in most of cases. In few cases it raised up to 0.012mV...Than i triead again to fine readjust null to obtain absolute zero...yet without succes...Quite expectable.
But, somethimes i am to lunatic about those things...i want to push more and more, so today i made experiment with one coil. I nulled it with attached capacitor 15nF parallel to RX. Final voltage was 0.008mV...
I figured way how to achieve absolute zero; i put (carefully chosen) few very small pieces of Al foil inside coil housing, covering few spots on coils.Must mention those pieces are not connected anyhow in coil setup. Those pieces actually play role of "foreign body" inside coil. By moving them slowly,carefully inside coil i found exact spots and gained absolute zero balnced coils!!!
Actaully those Al pieces provoked minor induction, enough just to balance coil to zero.Coil is finished., filled with mass.Drained...and now is ready for terrain work. I checked it with detector.....PERFECT!!!! I gained extra 2cm's on single coin!!! Stabillity is good as it was before. Discrimination also good...
What to say? Crazy experiment gave me crazy result!!
Now i am thinking other thing; so i put Al pieces - "coloured" metal...What should be if i put iron pieces ("non-coloured") instead Al???
Only way to find out is to make another coil and try. I am planing to do that tomorrow...
I do know what is all about....perfectly clear to me. But i would like to hear your opinions...?
Heh,heh,heh...!

P.S.
You should appreciate this! I gave up one of "master secret" here!

[mostafalesnar91]

Does this scope help me????

[waltr]

It is better than No scope.
A dual channel scope is greatly desired so that you can compare two signals.
This is what is needed to adjust coil null and phase. One trace shows the TX waveform and the second the RX waveform. Then you can see the amplitude and phase relationship between the two signals.