TESORO GOLDEN SABRE

[ivconic]

.....


I am also finishing this Tesoro Golde Sabre...
It will be ready in few days....
If not work....than i'll mail bomb here!
Best regards!



P.S.
white powder.....white powder....white powder.....

[Leto]

even more complete...

Originally Posted by unregistered
For golden sabre.
coils ca 6 mH

Open centre:

Transmit : 110 turns 22 cm. adjust with cap for 14 kHz
.25 mm wire
First rec. 18 turns 22 cm.( same size and turn direction as trans. coil)
Sec. rec. 165 turns 12 cm. in opposite turn direction as first rec. coil.
.25 mm wire
Go for ca 5 mV receive signal. ampl, rise for gold

As winding strength or size errors make a differents, you must do some adjustment for the 165 turns.
If you have to lift up the 12 cm coil to get a nulling : then you have to reduce the number of 12 cm turns.
If you have to move the 12 cm coil out of the center towards the 22 cm coil: then you have to add some 12 cm coil turns
Look at pin 7 from LF 353 for nice sinus signal, if not adjust the 15 nF cap.

If you have a much to large receive signal then you have to flip over the 12 cm receive coil.

Use graffit spray , make the receiver ground connection in the coil, this for the twisted pair effect.

Good luck.

Thanks to unregistered!!

For golden sabre.
coils ca 6 mH

Open centre:

Transmit : 110 turns 22 cm. adjust with cap for 14 kHz
.25 mm wire
First rec. 18 turns 22 cm.( same size and turn direction as trans. coil)
Sec. rec. 165 turns 12 cm. in opposite turn direction as first rec. coil.
.25 mm wire
Go for ca 5 mV receive signal. ampl, rise for gold

As winding strength or size errors make a differents, you must do some adjustment for the 165 turns.
If you have to lift up the 12 cm coil to get a nulling : then you have to reduce the number of 12 cm turns.
If you have to move the 12 cm coil out of the center towards the 22 cm coil: then you have to add some 12 cm coil turns
Look at pin 7 from LF 353 for nice sinus signal, if not adjust the 15 nF cap.

If you have a much to large receive signal then you have to flip over the 12 cm receive coil.

Use graffit spray , make the receiver ground connection in the coil, this for the twisted pair effect.

Good luck.

[Leto]

Love at first sight..

Few observations:

1.) This detector reject small iron objects when in disc. mode completly - in other words: minimum rejection level is well above nail rejection.

2.) But still objects like tin plated iron boxes are not possible to discriminate well agains other metals - so no mirracle here.

3) Notch feature is very interesting - kind of a analog accept-reject circuitry. For example I can filter (accept) ONLY my gold ring and no other metal make even a sound!!

4) Sound is really poor, it is about the same as CLIII. I belive this is the main difference between GoldenSabre and GoldenSabreII.

5) Coil. Thanks Max I also saw that KT315 post:
rx 1.35mH 12ohm
tx 10mH 55ohm
Hm - I actually made a good gimmick to reverse Tx/Rx of whites DD coil to test GoldenSabre. But still I wonder if those values are correct. Will try to hunt for best coils in OO configuration. First I need Tx for 12-15 kHz - then I'll experiment with different Rx inductances.. and post results here.
ANY IDEAS, HINTS ...

6) Ground adjust trimmer: It works perfect - I can adjust it to the worst ground ever (I have few bags of detectors-nightmare: these are from one layer of soil near iron smelting furnace we found at excavations last year).

7) About those 4.7uF caps: I use polyester (100V) but are way too big for this board - so I orderd few multilayered-ceramics probably well enough for the job.

porkluvr thanks for non-blury shematic and corrected values. These are also corrected on parts-placement (componentzijde) picture kurtie100 posted. No mistakes also on PCB - we could just wish for such complete projects like this one.

[porkluvr]

Golden Sabre schematic -

Try it again-

I had a problem with the image quality of the schematic posted above so I have posted very nice copy of a PDF that I received from Bojidar Steff (many thanks Bojidar). I included some notes covering circuit errors you guys mentioned.

I recommend to anybody who needs a working spice simulator: LTspice is infinitely cheaper than PSpice. I wish they would pay me for recommending it, but since it's free I don't foresee that happening.
http://www.linear.com/designtools/so...witchercad.jsp

It was originally designed to showcase Linear's power products, but is is good for "predicting" the operation of Tesoro's oscillators, charge pumps, integrators, sound, and etc. I can help if anybody wants to try it but gets stuck.

[porkluvr]

Golden Sabre

Please disregard this - see next entry.

[chemelec]

Where to find those 4,7uF ?
I have 2,2uF....Is it big problem if use those instead 4,7uF.....How much it will affect signal and overall performances?

Considering the Relatively Low Frequencys involved, Just use 4.7uF Electrolytics.
Possibly Bypass each one with a Parallel 1000pF cap to Increase the High Frequency response of the Electrolytic.

Gary

Where to find those 4,7uF ?
I have 2,2uF....Is it big problem if use those instead 4,7uF.....How much it will affect signal and overall performances?

[Max]

sweet words: IT WORKS

Thanks to you Max, you pointed me in right direction...problem was with low inductivity of TX coil I used. I hooked the tx section to RX coil and used TX as recieve coil. --> and it worked.
Voltages are: +8V / -6.2V

Can not make depth tests yet as I have to make suitable coil first, original circuit is for 12kHz - now it is running at only 5.1kHz. But the coil is good enough to test discrimination:--> it is working too

I belive it will be quite decent detector with proper coil just need some time to make it..
Any idea how many turns 12kHz Tx coil needs? Any other information on old Tesoro coils?

Big thanks also to kurtie100, his friend and original remaker of this circuit.
Project is complete with NO mistakes at all (using proper coil).

P.S. I found two versions of Golden Sabre schematic on net, use the one kurtie100 posted in this thread.

Hi Leto,
nice to ear it works ! Could be also for me another funny project to make in some spare time.

Tesoro coils : think you could use an early lobo design (dd type) params are:
(data from an old kt315 post)

rx 1.35mH 12ohm
tx 10mH 55ohm

Also concentric would be useful I think and with better pinpointing ...just is a bit more difficault to obtain and tune with existing caps values.

Best regards,
Max

Golden pcb looks OK ....
Wrong schematic drawing: after sens comp. 100k -> anode 1n4148 ?
Schematic some wrong resister and cap values.
In -5v power converter 47k = 4k7
In ground/all matal 150pF is 15 pf
Freq = 14Khz.
For ground balance potmeter adj. :
Make a 5 cm disc from epoxy (polyester) 2 comp., include some small iron in it (the stuf you cet from sawing iron, 2 to 3 tee spoons). adjust for not detecting is.
Check now that you can detect large silver coin !! ( to far adjustment and you will not find large silver !! Tray it out.

Good luck

[Leto]

PERFECT...

sweet words: IT WORKS

Thanks to you Max, you pointed me in right direction...problem was with low inductivity of TX coil I used. I hooked the tx section to RX coil and used TX as recieve coil. --> and it worked.
Voltages are: +8V / -6.2V

Can not make depth tests yet as I have to make suitable coil first, original circuit is for 12kHz - now it is running at only 5.1kHz. But the coil is good enough to test discrimination:--> it is working too

I belive it will be quite decent detector with proper coil just need some time to make it..
Any idea how many turns 12kHz Tx coil needs? Any other information on old Tesoro coils?

Big thanks also to kurtie100, his friend and original remaker of this circuit.
Project is complete with NO mistakes at all (using proper coil).

P.S. I found two versions of Golden Sabre schematic on net, use the one kurtie100 posted in this thread.

[Max]

I tried first the power:
positive rail:8.0V
negative rail: 0.74V - not even negative
Of course rest of the circuit not working, no oscillation, NOTHING!!



Hi Max, as you can see it looks like a >faked shematic< and consecutively someones failed PCB project..? PCB is really nice and no mistakes were found according to shematic.

I like discriminating abilities of this MD..with its notch accept/reject circuitry. Maybe it could be even usable to kick-out that pottery (redbrick) bothering you while still accepting targets above and below brick response.

Maybe I'll try to connect circuit to real +-5v supply, any ideas?

Hi Leto,
yes pottery make me crazy...and I'm actually dealing with some bandido disc stranges but interested in similar circuits too.

I think that something could be wrong in that schematic in the osc section:
- if you have no oscillation you can't get -5 volts from charge pump

I don't understand why there is a fet near tx transistor base...I think the error could be there. I think that polarization of tx transistor is wrong and that caused you have no oscillations at all.

The circuit can't provide real -5volt (like in bandido) but think it's not a real problem cause lm358/lm393 work happy also with -3v. What's little critical are lf353s that I had bad experience with lower voltages. But think it was correct for this circuit to have them. Maybe you could use ls204 instead of LFs having less problems but think you need to solve first voltage converter/osc problem.

To make a try you can:
- disconnect 1n4148 from collector of osc transistor
- short source and drain of fet tis75
Then you can test is oscillations are present and charge pump works
Do this without other components like ICs to avoid too load and other problems.
If you get oscillation ---> problem is in tis75 polarization network
If you can't get oscillations ---> problem is maybe transistor gain (too low) or resitors connected on base of it (passive polarization network).

If you solve that problem you can get steady -5v using 79L05 and increasing negative rail voltage to at least -8volts (dropout is 3volts) or better with an ldo negative voltage regulator for -5 volts (usually dropout is under 1v).

Best regards,
Max

[Leto]

I KNEW IT ..

I tried first the power:
positive rail:8.0V
negative rail: 0.74V - not even negative
Of course rest of the circuit not working, no oscillation, NOTHING!!

Originally Posted by Max
Hi Leto,
unfortunately I don't know anything about this schema. But, do you think it's not working (a joke ?) or something wrong ?
Why you decided to build this ? I mean there is bandido II umax circuit and works pretty well if you have original coil or make a good one yourself...
There is any advantage in depth respect to bandido II or is just curiosity ???

Hi Max, as you can see it looks like a >faked shematic< and consecutively someones failed PCB project..? PCB is really nice and no mistakes were found according to shematic.

I like discriminating abilities of this MD..with its notch accept/reject circuitry. Maybe it could be even usable to kick-out that pottery (redbrick) bothering you while still accepting targets above and below brick response.

Maybe I'll try to connect circuit to real +-5v supply, any ideas?

[Max]

Guess what..
I looked at shematic and almost all the parts were also in my el. junque box.
As I was free yesterday I etched and populated the board..
.. few parts are still missing -10caps and IC-sockets

My question would be ->
What are those 4.7uF "BI" caps? On blury shematic "B.Pol[?]"
Probably bi-polar (non-polarised)??
I can attach large 4.7uF (100V) polyester caps, but are really BIG.

Why IC-sockets? -> because If I'd bet:
I guess it's about 4:1 in favor of project-non-working..Remember Ivconic's Gold Demon?
So I'd like to save at least IC's when my hammer strikes.

Hi Leto,
unfortunately I don't know anything about this schema. But, do you think it's not working (a joke ?) or something wrong ?
Why you decided to build this ? I mean there is bandido II umax circuit and works pretty well if you have original coil or make a good one yourself...
There is any advantage in depth respect to bandido II or is just curiosity ???

I think that making good coils for tesoro's is the most difficault part...if schematic is ok. Because they need very well done nulling.

Best regards,
Max

[Leto]

LETS BET

Guess what..
I looked at shematic and almost all the parts were also in my el. junque box.
As I was free yesterday I etched and populated the board..
.. few parts are still missing -10caps and IC-sockets

My question would be ->
What are those 4.7uF "BI" caps? On blury shematic "B.Pol[?]"
Probably bi-polar (non-polarised)??
I can attach large 4.7uF (100V) polyester caps, but are really BIG.

Why IC-sockets? -> because If I'd bet:
I guess it's about 4:1 in favor of project-non-working..Remember Ivconic's Gold Demon?
So I'd like to save at least IC's when my hammer strikes.