TESORO GOLDEN SABRE

[nelson]

Hi,
I saw those,but can't understand there is one more W point near batt-, that is unused?
YES

And from second picture:
lets use L1 for left and L2 for right winding!
FOLLOW THE SAME WINDING DIRECTION

I have to conect the two faradey shields on the windings and the two windings ends and then conect this point with faradey shield on the cable and one of the cores(black)!
JUST FOLLOW THE PICTURE. BOTH FARADAY SHIELDS ARE CONNECTED TOGETHER.
The red core to L1 winding start?And blue core to L2 start?
STAR LEADS GOES TO RX AND TX ON THE BOARD, END LEADS GOES TO SHIELD
Regards

Nelson

hi

Can you tell me have this TESORO pinpoint?

[Geto]

To nelson

Hi,
I saw those,but can't understand there is one more W point near batt-, that is unused?

And from second picture:
lets use L1 for left and L2 for right winding!
I have to conect the two faradey shields on the windings and the two windings ends and then conect this point with faradey shield on the cable and one of the cores(black)!
The red core to L1 winding start?And blue core to L2 start?
Thanks



I will make coil like this for first time!

[nelson]

Hi Geto, here i m sending a copy of a good job made by Ivconic, that shows graphicaly how to connect pots and swithches.
Regards
Nelson

Hi,
How did you conect the switches?I still cant get that!

[Geto]

To nelson

Hi,
How did you conect the switches?I still cant get that!

[nelson]

I dont have the time by now, so this will be make sooner.
Regards
Nelson

Nelson!
What are the results afther nuling?
I am working now too!
Thanks

HI

Nelson!
What are the results afther nuling?
I am working now too!
Thanks

[nelson]

Thanks Max
Nelson

Hi,
yes it is.

Best regards,
Max

[Max]

TO GET MORE CLEAR, DO YOU MEAN THIS CONFIGURATION SHOW ON THE PICTURE?

BEST REGARDS

NELSON

Hi,
yes it is.

Best regards,
Max

[nelson]

TO GET MORE CLEAR, DO YOU MEAN THIS CONFIGURATION SHOW ON THE PICTURE?

BEST REGARDS

NELSON

Hi,
connect tx coil to osc circuit (pcb pads). This way you get the oscillating magnetic field be generated all around the tx coil.
Connect capacitor and resistor in parallel to rx leads, and then the voltmeter accross leads too.
Move to null as described. When find minimum fix the rx coil with tape etc in many point , then recheck and if necessary fix again.

When you read a small few mv voltage you can test performance, disconnecting capacitor and resistor and connecting rx coil leads to pcb.

Best regards,
Max

[Max]

Ok Max and thanks for your help.
One more question, should i have to place the resistor and capacitor in series to one lead or shoud i have to conected it to each leads in parallel?
Both coils has i understood must be of the circuit and the frequency injection should be conected to the rx coil leads. Where should i have to place the multimiter leads?
In advance thanks.
Regards
Nelson

Hi,
connect tx coil to osc circuit (pcb pads). This way you get the oscillating magnetic field be generated all around the tx coil.
Connect capacitor and resistor in parallel to rx leads, and then the voltmeter accross leads too.
Move to null as described. When find minimum fix the rx coil with tape etc in many point , then recheck and if necessary fix again.

When you read a small few mv voltage you can test performance, disconnecting capacitor and resistor and connecting rx coil leads to pcb.

Best regards,
Max

[nelson]

Does anyone have the manual owners for Tesoro Golden Sabre?
Regards
Nelson

Ok Max and thanks for your help.
One more question, should i have to place the resistor and capacitor in series to one lead or shoud i have to conected it to each leads in parallel?
Both coils has i understood must be of the circuit and the frequency injection should be conected to the rx coil leads. Where should i have to place the multimiter leads?
In advance thanks.
Regards
Nelson

[nelson]

Ok Max and thanks for your help.
One more question, should i have to place the resistor and capacitor in series to one lead or shoud i have to conected it to each leads in parallel?
Both coils has i understood must be of the circuit and the frequency injection should be conected to the rx coil leads. Where should i have to place the multimiter leads?
In advance thanks.
Regards
Nelson

Hi Nelson,
nice to ear it works. About performances I think the problem is in coil nulling and I can suggest you a way using a multimeter.

I've tested that just one time, cause I use scope for that thing, but maybe you could find description useful.

You need a good ac voltmeter, with 1mV sensitivity. Also an old good quality multimeter would be good for that purpose. Watch at internal resistor printed on the panel of the instrument. You need at least 20Kohm internal resistance for cc and at least 4Kohm resistance for ac measures.
There are many that have 40Kohm/V in ac or even more.
The higher the better. You could use also a digital multimeter with true RMS in ac measures, but I suggest you start with analog if you own a good one. Sometimes digital meters have their troubles working with so smaller signals in ac , much depends on internal adc speed etc. so use as second choice and only with hi-brand products like lafayette, hc, etc

OK. you need a resistor load on rx coil leads (1kohm to 10kohm would be ok) and a suitable capacitance like you have in the circuit. You just need a perfect sine signal on rx at tx freq. and to minimize it as low as you can.

With that configuration connect the ac mvoltmeter and read , then moving slowly rx coil (or tx coil or both) try to keep signal low, to find point of minimum. You must reach under 3mV pk-pk that means about 2.12mv value on your ac scale. If you can stay under 1mV and your coil will be ok.

Another good test is reversing rx lead that go to circuit, cause signal must be in phase to get maximum sens and right disc, I've that behaviour on bandido.

Best regards,
Max

[Max]

To unregister, Ivconic, Max and all friends on the forum.

Today i finish coils:
TX coil is 101 turns, 0.25 mm wire, 5.6 mH, resistance 26.2 ohms.
RX coil is 107 turns, 0.25 mm wire, 6.45 mH, resistance 27.4 ohms.
Diameter of both coils is 19 cms.

The detector has all schematics components except LM308 that was replace by TL081.

TEST:
For testing purposes i place both coils on a wood table, overlap about 4 cms from each edges. The coils were connected to the MD with USB computer cable ( i removed both conector from it), this cable has 4 legs and shield.
I power the detector with 12 volts 4 amps batery.

RESULTS:

Operating frequency: 13.4 Khz
Sound: Low and steady. When turned on sound is very high and after a few seconds goes down.

Used elemets on test: 1.7 cms copper coin, 1.9 cms weeding gold ring, 4 inches nail, 1.2 cms zinc coin

The gold ring was detected at about 10 cms
1.7 cms coin detected at about 7 cms
1.2 cms coin 9 cms
Nail 6 cms

Results are very poor by now, may be the coils is to small or inductances are wrong

Discrimination works ok and only big iron elements are detected, not the smallest ones (nails).

Pingpointing is excellent

To inconic, can you help me on how to tune coils with a multimeter?
Do you think the problem can be inductances or diameter?

TL081 seems to work ok and i have not advice any problems with it.

Sorry for my english, but i hope this little report can by understand i be a help for anyone.

Regards
Nelson

Hi Nelson,
nice to ear it works. About performances I think the problem is in coil nulling and I can suggest you a way using a multimeter.

I've tested that just one time, cause I use scope for that thing, but maybe you could find description useful.

You need a good ac voltmeter, with 1mV sensitivity. Also an old good quality multimeter would be good for that purpose. Watch at internal resistor printed on the panel of the instrument. You need at least 20Kohm internal resistance for cc and at least 4Kohm resistance for ac measures.
There are many that have 40Kohm/V in ac or even more.
The higher the better. You could use also a digital multimeter with true RMS in ac measures, but I suggest you start with analog if you own a good one. Sometimes digital meters have their troubles working with so smaller signals in ac , much depends on internal adc speed etc. so use as second choice and only with hi-brand products like lafayette, hc, etc

OK. you need a resistor load on rx coil leads (1kohm to 10kohm would be ok) and a suitable capacitance like you have in the circuit. You just need a perfect sine signal on rx at tx freq. and to minimize it as low as you can.

With that configuration connect the ac mvoltmeter and read , then moving slowly rx coil (or tx coil or both) try to keep signal low, to find point of minimum. You must reach under 3mV pk-pk that means about 2.12mv value on your ac scale. If you can stay under 1mV and your coil will be ok.

Another good test is reversing rx lead that go to circuit, cause signal must be in phase to get maximum sens and right disc, I've that behaviour on bandido.

Best regards,
Max

[nelson]

To unregister, Ivconic, Max and all friends on the forum.

Today i finish coils:
TX coil is 101 turns, 0.25 mm wire, 5.6 mH, resistance 26.2 ohms.
RX coil is 107 turns, 0.25 mm wire, 6.45 mH, resistance 27.4 ohms.
Diameter of both coils is 19 cms.

The detector has all schematics components except LM308 that was replace by TL081.

TEST:
For testing purposes i place both coils on a wood table, overlap about 4 cms from each edges. The coils were connected to the MD with USB computer cable ( i removed both conector from it), this cable has 4 legs and shield.
I power the detector with 12 volts 4 amps batery.

RESULTS:

Operating frequency: 13.4 Khz
Sound: Low and steady. When turned on sound is very high and after a few seconds goes down.

Used elemets on test: 1.7 cms copper coin, 1.9 cms weeding gold ring, 4 inches nail, 1.2 cms zinc coin

The gold ring was detected at about 10 cms
1.7 cms coin detected at about 7 cms
1.2 cms coin 9 cms
Nail 6 cms

Results are very poor by now, may be the coils is to small or inductances are wrong

Discrimination works ok and only big iron elements are detected, not the smallest ones (nails).

Pingpointing is excellent

To inconic, can you help me on how to tune coils with a multimeter?
Do you think the problem can be inductances or diameter?

TL081 seems to work ok and i have not advice any problems with it.

Sorry for my english, but i hope this little report can by understand i be a help for anyone.

Regards
Nelson

Hi,
Did you test your detector?
What are the results with this changes?
Hope you acive good results!