TESORO GOLDEN SABRE

[tiktak]

Hi

Hi,
Ivconic I have tryed this yours new coil,but very poor results!
I have make the same number of turns and used 0,25 without varnish/and 0,27 with varnish/
I have the same housing and wanna try this coil!
Can you tell the resistance of the windings?
Man I have saw 40 cm coil!It were able to detect VERY deep!!!
Can you try making one!
This housings that we use have a larger ones I think 33 and 38cm.
Its worh the work
Thanks

[Max]

which one ????

Hi,
Max.
I have broke two batteries with this circuit.I have made exacly the same as on the picture.I have conected + to diode and then to Vin;Vout to 20 ohm resistor and then to adj.and to battery +!!
I have charged for 12 hours.
When batteries were with their own charge they worked good,I have played to discharge them a little before conect to circuit and charge~~!!
Bad news NOW when I conect the battery that should be charged and switch on the voltage drops from 12. to 6.6!!!
When I measure the cells one buy one there are 3 cells that show 0,22;0,12 and 0,01!
Why?
Please help.

Hi,
which circuit ? The first limiter only or this of the picture below ?
I've used both for years an never had troubles... maybe you made some mistake.

Both way works...

use the one below... require less care than the simpler.
--
LIMIT IS

0.6/R4 ---> 0.6/2.2 = 272mA that is always hi for e.g. 1.2Ah battery

Good value for 1.2Ah battery is 4.8 ohm (limit at 125mA).

Circuit works perfect with both gel-type or adsorbed-glass-mat.
Just rotate the trimmer to get 13.8 V at output.
Use an AC 18+V transformer with it.
--

You can leave it attached to the battery for more than 10hours without problems... I do that way.

Let me know.

"Bad news NOW when I conect the battery that should be charged and switch on the voltage drops from 12. to 6.6!!!"

If your charger goes down the fixed charging voltage that means :
- not enough current delivered - e.g. you have too small transformer
- some kind of protection circuit down the voltage to a safety area for e.g. semiconductors

Using the circuit I've reposted here you'll notice small changes on voltage due to the charge: these are normal.

When battery is fully charged you'll get there a voltage above near 13.8v with charger connected, as the output with no load of charger. Current drop to zero.

Depending on the battery model when you disconnect it from charger happens always a small voltage reduction e.g. to 13.6, 13.5 : normal.

Kind regards,
Max

PS: some sla batteries have max cell voltage of 2.15V so give you max of 12.9v at full charge: circuit works good also for these... but better if you set output voltage at 13.2v with no load

[Max]

this is the pinout of LM317T... maybe this was the error ???

The circuit schematics could be confusing... look at pinout of device....
the adj is not a center but at left side of it...

Was this the mistake ?

[Max]

Hi Ivconic,
I have a dubt now on which version of LM308 could be better...

I mean, I've tested the LM308N cause find 2 recovering them from another circuit... and the TGS is going well with them, seems better than with tl081, of course... but I can't use them cause I have to replace where I found them sooner or later.

So I have to find 2 new, or used... from other stuff.

Have you used the LM308N or the LM308AH ? ... cause I know there were some differences , though really small things.

So before I dismantle things to find 2 ... better know what to search !

Please let me know.

Kind regards,
Max

[Max]

Hi Ivconic,
to be more explicit... the metal can or standard dip ones ?

Cause I think can find the AH... with a bit of luck.

They introduce less noise and have some different freq. response... though circuit should be the same on the chip.

Let me know if you have tryed the metal can... TO-99.

Kind regards,
Max

[ivconic]

...

...
Some of coils i've used on 255x137mm former...
110w=24,7ohms=6,68mH
105w=22,3ohms=6,11mH or 6,55mH constrained...
100w=21,2ohms=5,61mH or 5,99mH constrained, giving 14,6kHz

Working good, excellent! Very good depths....
Your report about poor results doesnt mean much here. Even when respecting all i done on my coils wont guarantee you good results...Much other things to be done to make it work good....Try again!


Max i used "N" type....

Well, i was pushed to make some compromises yesterday, so again used TL081a instead LM308....Put enormous effort to undestand how to make it work good and.....piece of cake!

Yes TL081a could be used...(sheeeesh i already told it cant)....
No major corrections at all, just as "Sens." do not use pot but trimmer on pcb, adjust it to work calm and fine and leave it on pcb for good....
Depths remains same as with LM308...only "Sens." stays as trimmer preset....
No more "Sens." knob on front panel....

Hard compromise...but no other solution so far...
Regards!

[nelson]

Good Ivconic, but tell me what is the reason to use trimmer on pcb, instead of pot on front panel?
Are there any RF losses thru wires that came from pcb to front panel?
If this is rigth, what about using shielding wires?

In advance many thanks

Regards

Nelson


Well, i was pushed to make some compromises yesterday, so again used TL081a instead LM308....Put enormous effort to undestand how to make it work good and.....piece of cake!

Yes TL081a could be used...(sheeeesh i already told it cant)....
No major corrections at all, just as "Sens." do not use pot but trimmer on pcb, adjust it to work calm and fine and leave it on pcb for good....
Depths remains same as with LM308...only "Sens." stays as trimmer preset....
No more "Sens." knob on front panel....

Hard compromise...but no other solution so far...
Regards!












[/quote]

[tiktak]

Hi

Hi,
Max.
I have used the same picture to see what is the LM317T pinconfiguration.
I used LM317T,1N4007 diode and 20 ohm resistor wired the way that you show.
You told me to charge over night or for 12 hours.
I make the same thing.
I now that have mistake somewhere but can't find what exacly.
When the batteries were new with their own charge they were working fine,but now when I charge them its look like 3 cells are damaged.
I have spend much money around this suply variant!!
THANKS

[tiktak]

Hi,

Hi,
Ivconic.
Sorry the probleme were in battery!
My voltage drop too fast!!!
When tryed with ac/dc adapter conected to TGS your coil work excelent!!
Can you tell me how to null beter my new multimeter have 200m in AC this is under 2 volt range should be better right?
Or I should use 2 volt range and try to keep .018?

p.s.The coil I saw were 40cm!!!!
Very respectating.
I were surprised!My test coin were detected at 60cm in air WOW.!
So I am wondering what TGS can do with something like this?
Thanks

[Max]

Hi,
Max.
I have used the same picture to see what is the LM317T pinconfiguration.
I used LM317T,1N4007 diode and 20 ohm resistor wired the way that you show.
You told me to charge over night or for 12 hours.
I make the same thing.
I now that have mistake somewhere but can't find what exacly.
When the batteries were new with their own charge they were working fine,but now when I charge them its look like 3 cells are damaged.
I have spend much money around this suply variant!!
THANKS

Hi,
problem is that with this kind of batteries one can't make mistakes... or for sure it will result in a damage to the cells.

This is the real "limit" of most charger schematics... respect e.g. to bought chargers.
Otherwise they work well if proper wired and a bit of extra care is taken to prevent damages... the first thing to look at is the current delivered when charge start. Current must stay always under safe limit so cannot be e.g. above 1/4 of battery capacity, much better if low as 1/10 of it.

Circuit like the ones I've posted are in practice current limiters based on LM317 plus some extra components e.g. in the second schematic.

Are easy... and they work if properly built and used... but if e.g. the LM317 have problems e.g. a thermal runaway cause heatsink too small etc they could give catastrophic effects.

The best thing to do in the hypotesis that cases happen is always put a fuse on the supply side, I mean or an auto-fuse (e.g. 250mA fast) or a normal old type for higher current limits... so if things go wrong you could lose the fuse as maximum damage but not the battery ! Next time put a fuse with double current rating of your charging limit.

Wasting money is always an hard lesson but sometimes is also useful lesson!

Kind regards,
Max

[dino]

GS

Hello all. I done my sonde 255*137mm with wire 0.25.
RX 108 TX 102 coils
power +8V-6,27V
max range 40cm
coin 5cm
no dicrimination.
Is it correct PCB or Shematic? And I dont qiute undrstand the meaning of NOCH.... sorry bad english.
Regards Dino

[porkluvr]

notch = reject

Hello all. I done my sonde 255*137mm with wire 0.25.
RX 108 TX 102 coils
power +8V-6,27V
max range 40cm
coin 5cm
no dicrimination.
Is it correct PCB or Shematic? And I dont qiute undrstand the meaning of NOCH.... sorry bad english.
Regards Dino

Hello Dino -
Notch means reject, nadir. Are you building the Golden Sabre or the GS Lite (GS, GSL)? Notch should not be issue if you built GSL.

If you built GS, then maybe you should switch the notch circuit off. Eliminate notch until everything else is working OK.

When you say "is it correct", which variation are you talking about? Be specific. If you have detection at 40 CM, something must be working, so that may be a good start, but you must try to explain which version that you are building.

[ivconic]

Thunders !


Rain,flood,thunders..! I cant be logged here for longer, it is risk to burn my pc..... So i'll be quick;
Yes Nelson i was thinking to use shielded cable to "Sence." knob....but from the other hand, what use of Sence. knob anyway? If TL081 are used, only way to make device works is to lower Sensitivity at almost lowest point and keep it "fixed"...So better to use trimmer,adjust it and forget it for good...
This doesnt affect sensitivity and depths much....maybe 1-2cm lost overall...i can live with this...can you?
Of course until find LM308 to buy by reasonable price, cose there are few suppliers here in Serbia, asking much money for LM308...from 5 up to 11 euros !!!! This offends my intelligency so i am refusing to waste such money on obsolete op-amp...I'll rather use TL081 which cost 50cents... Suppliers drop dead! Keep those LM308 and enjoy having them....Hah,hah,hah!!!!

Also there is another situation here....very funny....Dont have conditions to write here and now, but i will prepare detailed text and post in a day or two..
It is about selling Minelab X-Terra coils for 180 euros by piece!!!!
Local Minelab "agent" (i doubt Minelab is awared of this one..."agent") is claiming that prices are raised cose to many people here in Serbia are "hacking" those coils and making copies.....so they had to raise prices!!!???
What a stupid logic???
If somebody offer me coils by fair prices i WOULD NOT MAKE NAITHER ONE MORE COIL IN MY LIFE!!! I WOULD RATHER PAY FOR ORIGINAL ONE!
Guys from Minelab read this and think! Come here in Serbia, open shop and i'll be your favorite customer...i swear!

For example Tesoro...? Why should i bug myself making coils for Golden Sabre if Tesoro offers me, here in Serbia, their coils by fair prices...? i 'll rather pay 80-100 euros for one good Tesoro coil than to waste money,nervs,material to make handmade.....I am not that enthusiast!

No, those idiots are not "agents" those are frauds and thieves, buying Minelab coils for 80-120 euros abroad and that trying to sell by almost double prices here....Who is stupid here?

Minelab Co. should be introduced with this situation here....Also other big "players".....Serbia is small country yet very interesting market for those, due huge nuber of propsectors...

[Max]

Rain,flood,thunders..! I cant be logged here for longer, it is risk to burn my pc..... So i'll be quick;
Yes Nelson i was thinking to use shielded cable to "Sence." knob....but from the other hand, what use of Sence. knob anyway? If TL081 are used, only way to make device works is to lower Sensitivity at almost lowest point and keep it "fixed"...So better to use trimmer,adjust it and forget it for good...
This doesnt affect sensitivity and depths much....maybe 1-2cm lost overall...i can live with this...can you?
Of course until find LM308 to buy by reasonable price, cose there are few suppliers here in Serbia, asking much money for LM308...from 5 up to 11 euros !!!! This offends my intelligency so i am refusing to waste such money on obsolete op-amp...I'll rather use TL081 which cost 50cents... Suppliers drop dead! Keep those LM308 and enjoy having them....Hah,hah,hah!!!!

Also there is another situation here....very funny....Dont have conditions to write here and now, but i will prepare detailed text and post in a day or two..
It is about selling Minelab X-Terra coils for 180 euros by piece!!!!
Local Minelab "agent" (i doubt Minelab is awared of this one..."agent") is claiming that prices are raised cose to many people here in Serbia are "hacking" those coils and making copies.....so they had to raise prices!!!???
What a stupid logic???
If somebody offer me coils by fair prices i WOULD NOT MAKE NAITHER ONE MORE COIL IN MY LIFE!!! I WOULD RATHER PAY FOR ORIGINAL ONE!
Guys from Minelab read this and think! Come here in Serbia, open shop and i'll be your favorite customer...i swear!

For example Tesoro...? Why should i bug myself making coils for Golden Sabre if Tesoro offers me, here in Serbia, their coils by fair prices...? i 'll rather pay 80-100 euros for one good Tesoro coil than to waste money,nervs,material to make handmade.....I am not that enthusiast!

No, those idiots are not "agents" those are frauds and thieves, buying Minelab coils for 80-120 euros abroad and that trying to sell by almost double prices here....Who is stupid here?

Minelab Co. should be introduced with this situation here....Also other big "players".....Serbia is small country yet very interesting market for those, due huge nuber of propsectors...

Hi Ivconic,
I agree on coils... too hi-prices for new original coils. Even some that are of the few reasoning manifacturers on the price of detectors and accessories ask sometimes too much.

I've some originals and I'm happy with them, bought at reasonable price... but sometimes looking on the net... oh man! So hi prices!

Not to talk of some "top-of-the-range" manifacturers that for me are somehow crazy asking e.g. 200 eur for a standard-size VLF coil !

Not to talk of other kind of original coils... even higher prices !

They are mad, from my point of view... I mean they made big bargains of course... but one must be out of control for to sell a bunch of copper wire and some plastic/epoxy for 300 or more eur... or maybe buyers are crazy... anyway....

Yes, tuning, machinery, good materials etc etc of course, but too hi-prices for common mortals! Price is totally unrealistic !

Probably production cost is under 10$ each for coils e.g. untill 11'' diameter. That's the problem.

It's a kind of joke... if they sell at low prices people could start thinking "these coils are not soo good, can't be..."... and so a genius of marketing have suggested them of selling hi-price as they can!
They have no shame !

I can buy e.g. a complete VLF made in China for 15eur (even working) and have to spend 300eur for a brand coil cause of some marketing genius !???

They use power on price to keep it high cause most of people cannot build a good VLF coil ! Haven't enough skills! Here is their power.

That's where this forum is great I think. Democratic.

Here even few skilled people can make their coil... and then leave the BIG COMPANIES stay with their original 300eur coils on the shelf.

Kind regards,
Max

[nelson]

Ok Ivconic. My problem is that my TGS with TL081, runs fine, but i can not get more than 22 cms for a 1 cms coin on air.
So has i understand, i can get a few more deep just by adding a trimmer on pcb instead of pot for sens.. Is this correct?

I just wanna make shure if this will benifit my actual performance.

Regards

Nelson


Yes Nelson i was thinking to use shielded cable to "Sence." knob....but from the other hand, what use of Sence. knob anyway? If TL081 are used, only way to make device works is to lower Sensitivity at almost lowest point and keep it "fixed"...So better to use trimmer,adjust it and forget it for good...
This doesnt affect sensitivity and depths much....maybe 1-2cm lost overall...i can live with this...can you?