TESORO GOLDEN SABRE

[kt315]

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

[mostafalesnar91]

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

[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]

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!!

[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.

[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/showthread.php?15710-TGSL-Complete-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.

[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/forumdisplay.php?18-Silver-Sabre-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!!

[mostafalesnar91]

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

[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/forumdisplay.php?18-Silver-Sabre-Bandido-TGSL

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

[Qiaozhi]

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

That's not surprising ... because you're supposed to null to a 20 degree offset between TX and RX, not to the minimum null.

[mostafalesnar91]

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

[mostafalesnar91]

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

[Nandor]

One solution to reduce noise could be a new pcb with a quad opamp for the filters so it would be much smaller and compact, like the IDX pcb.
What do you think?

[Nandor]

Took some measurements today, Rx was disconnected from the coil. At the output of the preamp it had 12mVpp distorted line with a few peaks, not similar to any kind of sinewave. The frequency was unreadable, was jumping from 50hZ to several Khz. After that I measured the filters output, 50Hz mains distorted signal. I have tried many points but I got the same results.
Anyways OP07 does not like my pcb as NE5534, at least OP07 works, NE5534 gives continous sound.

[waltr]

All of our detectors will pick up local EMI noise.
Many of us can not easily test detectors in our workshops due to this.

Any EMI noise will decrease the detection distance.

This is defiantly true of the TGSL I built and when my furnace kick on and testing is impossible.
I have also found some sites where the EMI noise levels are high.

There really is nothing that can be done if the environment has high EMI noise.