TESORO GOLDEN SABRE

[ivconic]

Hi,
very good Ivconic... I like it.

Now I'm tempted to make another TGS...

Kind regards,
Max

Max it would be much more constructive all we to gather and solve audio issue at TGS/TGSL.
If you have made TGS already, than you dont need to make this one so fast.
Just change all capacitors on your pcb with WIMA's. Try to select best possible transistor couple for chopper stage and exclude from pcb Notch part.
And voila, you have this one.
But resistent problem with TGS and TGSL's i made is audio!
I simply do not like so short "beep" it produces when coin is detected over 35cm...!
Yes it is absolute true, it can cleary detect 2.5cm coin at almost 50cm in air.Not problem on this at all.But But audio is mum,weak and very short.Twice shorter than audio produced on coin ..let's say 10cm away from coil surface.
Generally audio is poor at this detector. So .... i want louder and longer audio. Ok...not much louder but longer sound.
That is only issue left to be solved on this. Once we do that TGS/TGSL would become best coinshooter ever - trust me.
Best regards!

[Max]

Max it would be much more constructive all we to gather and solve audio issue at TGS/TGSL.
If you have made TGS already, than you dont need to make this one so fast.
Just change all capacitors on your pcb with WIMA's. Try to select best possible transistor couple for chopper stage and exclude from pcb Notch part.
And voila, you have this one.
But resistent problem with TGS and TGSL's i made is audio!
I simply do not like so short "beep" it produces when coin is detected over 35cm...!
Yes it is absolute true, it can cleary detect 2.5cm coin at almost 50cm in air.Not problem on this at all.But But audio is mum,weak and very short.Twice shorter than audio produced on coin ..let's say 10cm away from coil surface.
Generally audio is poor at this detector. So .... i want louder and longer audio. Ok...not much louder but longer sound.
That is only issue left to be solved on this. Once we do that TGS/TGSL would become best coinshooter ever - trust me.
Best regards!

Hi,
yes I know about weakness of audio stage... is the old problem with TGS, still unsolved. So far I've found the 1Mohm resistor at comparator (do you remember the KT315's idea ?) present also in other original tesoro's (like bandidoII) is good if detector is stable... give sharp commutation and partially solve that... but is not always suitable cause of noise and chatters.

What about using a monostable say 0.2-0.3 seconds wide ? Once triggered device will give a minimum duration to sound.

To stay on the theme of south american pistols... they heavy use monostables in audio stage to get clear beeps. (but problem with that stuff is that the beeps happen at random...)

Kind regards,
Max

[Fred]

Hi ,
Did you try increasing C25 at input of LM358 (on Ivconic schematic)? Maybe audio would last longer or sound better.
Also even if it was not necessary i could not resist to remove a few jumpers on Ivconic PCB, still respecting the good design he made.
Ivconic it´s yours ... you don´t like it throw it away.
Best regards,
Fred.

[simonbaker]

Thanks for pictures showing missing 1K placement, should help. Someday we'll get a complete PCB finally -- just kidding, we all appreciate your work extremely.

Question -- what is the jumper wire under the LM393 for? (see image. Excuse me if this was answered before)

[amtech2005]

TESORO GOLDEN SABRE

Thanks!
Sure thing Amtech 2005!
Nakky it is in the air, so far didnt tested it on the ground. I already have been seen few "boosted" detectors with fantastic results in the air.But those were very unstabile. On slice touch on coil those produces a lot of false signals. Not to mention touching cable or lowering coil to ground!!!
But this one is different. It is very encouraging, even now, this TGSL 1265 is absolute immune on any torture with cable and coil.No falses at all.
46cm in air on 1 euro coin means some 30-35 in the ground...medium soil, hopefully. But i will wait with claims until testing it properly. I also have excellent reference at home to compare with - Eagle Spectrum. So far TGSL 1265 performs much better on coins than Spectrum...! On large items ... let's say 20x20cm Spectrum is more than superior.
I know what is all about; TGSL's oscillator is very weak, producing limited em field. Other hand Spectrum's oscillator is stronger, producing stronger em field and covering larger area....
So it is good deal, TGSL to be used as hell of a coinshooter only, with smallest possible coil. I do intend to experiment with coils under 20cm in diammeter. And Spectrum will serve as powerfull prospecting machine mostly.
I always wanted powerfull coinshooter....now i have it. Job is done...

Again Great Work On this Ivconic!!! You know what you said earlier about the "weak Oscillator" on the TGSL-1265....This could be a big problem solved that we have not dicovered yet!! You might field test now and have no "False Signals"...Maybe too strong an Oscillation can cause hidden Harmonics which can cause "signal falsing". Like seeing Ghosts. Anyway, you now took the Golden Sabre to a Higher Level !!!.......Also....I see you used some metal cans for BC177 and LM308H ??A requirement -"Thermal" or just a personal choice / leftover parts ???.....Thanks.......Eugene

[ivconic]

Simonbaker...!? It is route from LM308 to comparator..
See schematic...

[ivconic]

Fred i tried that as many other simple mods (read - wild experimenting) but no progress...i never got what i really intended.....

About pcb...yes, it always could be better. Be free to correct routes you want. I will take any better soultion in future to make.
Regards!

[ivconic]

LM308H showed slice better performances than plastic version...or it was just my illusion?? Not sure, but since i had those..i used..

About transistors...well, good question!
In chopper stage i tried many combinations.From 2N3906 & 2N3904, BC557 & BC547....to BC107 & BC177. Last couple seems to work better than others. Voltage is a bit higher than with others; -6.5V...so more close to symmetry than -6.2V...
Full symmetry here is not needed, but i have feeling that performances are rising as voltages are more close to symmetrical..

[ivconic]

Hi,
yes I know about weakness of audio stage... is the old problem with TGS, still unsolved. So far I've found the 1Mohm resistor at comparator (do you remember the KT315's idea ?) present also in other original tesoro's (like bandidoII) is good if detector is stable... give sharp commutation and partially solve that... but is not always suitable cause of noise and chatters.

What about using a monostable say 0.2-0.3 seconds wide ? Once triggered device will give a minimum duration to sound.

To stay on the theme of south american pistols... they heavy use monostables in audio stage to get clear beeps. (but problem with that stuff is that the beeps happen at random...)

Kind regards,
Max

Yes i tried that many times.You are right, usually it is working very fine.
It is not only the loudness i want to achieve here, but lasting.
On very small coins, 4-6mm diammeter, audio is very short and fast. Good chances to be missed on the field. So i was thinking somehow to delay it.
Your idea is interesting. I could try that. Need some concrete schematic.
I will search my material for idea...

[simonbaker]

Simonbaker...!? It is route from LM308 to comparator..
See schematic...

Ok, I understand. Then the green trace from pin 3 of the LM393 must run underneath the yellow jumper and is connected to the green circular trace at the end of the jumper. That is a little confusing to see at first.

Now, to make the PCB -- don't we need an image without the jumper wires? Or did you post it somewhere?

(I'm not too experienced with this)

[simonbaker]

Ok, I understand. Then the green trace from pin 3 of the LM393 must run underneath the yellow jumper and is connected to the green circular trace at the end of the jumper. That is a little confusing to see at first.

Now, to make the PCB -- don't we need an image without the jumper wires? Or did you post it somewhere?

(I'm not too experienced with this)

Ok, I'm learning. I used the Sprint Layout instead of GIF and make the jumpers invisible, now I can see it clearly!

[ivconic]

Yup!
In print page you can choose layers to be printed or not.....easy!

[KingJL]

Yes i tried that many times.You are right, usually it is working very fine.
It is not only the loudness i want to achieve here, but lasting.
On very small coins, 4-6mm diammeter, audio is very short and fast. Good chances to be missed on the field. So i was thinking somehow to delay it.
Your idea is interesting. I could try that. Need some concrete schematic.
I will search my material for idea...

Max,
Ivconic,

Why not use the mechanism thay ML used in Relic Hawk, Musketeer? They stretch the target signal with the 470K - 100n filter network going into the LM339 comparator (between the 4053 pin 14 and the LM339 pin 6).

Regards,
J. L. King

[Max]

Max,
Ivconic,

Why not use the mechanism thay ML used in Relic Hawk, Musketeer? They stretch the target signal with the 470K - 100n filter network going into the LM339 comparator (between the 4053 pin 14 and the LM339 pin 6).

Regards,
J. L. King

Hi,
yes this is another option... but problem is at TGS signal is sometimes faint and only way to know if good is try this way.

Kind regards,
Max

[tiktak]

Hi,

Hi,
Ivconic.
Today I got an Idea and can wait to try it.
But I wanna now what you think.I remember that you or someone else here told that this 4,7 are responcible for sound dely!@
Look RH waht a hugh cap.Maybe if we use higher value on this one or choose higher voltage one?
What do you think is it worth?
Where you buy this WIMA's?
Unfortunatly I still cant find link for what you ask me.Maybe I have to go to trip soon.