TESORO GOLDEN SABRE

[Max]

Hi Max
You must not at zero crossing,because in that the GBE can't work,
just as you had post at page 57,the photo "F7,F8,F9,F10" show that you sample at the wave crest.so you can't get the max deepth.
Today i made some test,i found that in theory we can't get both max deepth and good ground balance.Good ground balance will lost some deepth.
an get more deepth will lost more ground balance.

Hi,
one signal is sampled at zero crossing, the other at peak (maximum of wave).

This was explained by Qiaozhi some (many) posts ago... but you can find similar procedures in Gifford's patents too... is the usual way to use syncronous quadrature demodulator... samples are phased out by 90°.

One used for geb/ferromagnetic, other is the main channel... once tuned GEB (rotating the axis of coordinate system) you'll get minimum reading on main channel for ground realted signals. This way you will ignore ground influence.

Kind regards,
Max

[Qiaozhi]

Hi,
one signal is sampled at zero crossing, the other at peak (maximum of wave).

This was explained by Qiaozhi some (many) posts ago... but you can find similar procedures in Gifford's patents too... is the usual way to use syncronous quadrature demodulator... samples are phased out by 90°.

One used for geb/ferromagnetic, other is the main channel... once tuned GEB (rotating the axis of coordinate system) you'll get minimum reading on main channel for ground realted signals. This way you will ignore ground influence.

Kind regards,
Max

This is correct.
The GEB channel is sampled at the zero-crossing point, because metal targets exhibit a phase-shift, but the ground signal does not. In this case, the ground signal gets ignored.

[zzy]

impossible come true

This is correct.
The GEB channel is sampled at the zero-crossing point, because metal targets exhibit a phase-shift, but the ground signal does not. In this case, the ground signal gets ignored.

Hi Qiaozhi and Max,

Your explain is very good, but in my test it's very strange.Today i test the TGS,I find that just like Max had post in page 57,The GEB channel is sampled at the peak point,the GBE is good.
乔治，I find that i set the GEB channel sampled at the zero-crossing point,the GEB can't work at all.I test in the loess soil.
Max i also use a ferrite pole to test,i find it can also makes phase shift in the Rx coil.I set the GEB channel sampled at the peak point,another channel sampled at the zero-crossing,the sense and the GBE were work good. but the is not at the max,loss about 8cm in deepth.
Very sorry my bad english.

[Max]

Hi Qiaozhi and Max,

Your explain is very good, but in my test it's very strange.Today i test the TGS,I find that just like Max had post in page 57,The GEB channel is sampled at the peak point,the GBE is good.
乔治，I find that i set the GEB channel sampled at the zero-crossing point,the GEB can't work at all.I test in the loess soil.
Max i also use a ferrite pole to test,i find it can also makes phase shift in the Rx coil.I set the GEB channel sampled at the peak point,another channel sampled at the zero-crossing,the sense and the GBE were work good. but the is not at the max,loss about 8cm in deepth.
Very sorry my bad english.

Hi,
I don't know... maybe you have swapped rx coil leads ? This will create 180° phase reversal on your RX signal... and can create confusion here.

What I have is that with settings I showed here... (changed a bit but are about the same now) I got really good results both with ferrite and on soil.

With ferrite I can disc almost totally apart small cracks at few mms really short distance and still detect silver from very far, even if not so far as when geb is tuned out... sure.

Same happens but with less signal reduction (so really far detection) with e.g. an half-crown that's composite copper-nickel coin 3.2cm diameter.

I found so many items on soil with TGS that I'm sure this is the right setting !

I had problems with early solution of GEB trimpot and changed for a panel mounted control: I change from time to time according to soil to avoid device beeps due to vertical oscillations during sweeps.

Qiaozhi: do you think/remember I have right setting on my TGS (do you remember the pictures I've posted here some months ago ???) ?

If I remember well you told me it was all like expected....

Kind regards,
Max

[tiktak]

Hi,

Hi,
Max how are you?
I have a queston Did you used Tesoro Royal Sabre?
Think that have some interested features that can be integraited in TGS!
Also what you think about the depth?Will it be deeper?
Thanks

[Max]

Hi,
Max how are you?
I have a queston Did you used Tesoro Royal Sabre?
Think that have some interested features that can be integraited in TGS!
Also what you think about the depth?Will it be deeper?
Thanks

Hi,
no I haven't till now, but I think many tesoro's behave the same.

For example I have both bandidoII and TGS and are somehow similar about performances and features, both with fine disc expecially (in my case) TGS.

I think depth is not an issue if we consider all that schematics that are pretty close one another... the range you can get with TGS you can get also with bandidoII if use good components and do good work when you clone device. I have very good depth on bandidoII but have better disc on TGS.

It's a problem due maybe to some components values that were wrong or something about other components.

If you compare many schematics you'll see many things similar. E.g. in silver you have pretty similar oscillator that is in others etc... there are 2 basic osc in uMax series... the ones with zener and the ones without. Zener is there to fix amplitude and in some models there's the osc without it (e.g. in bandidoII).

Then few differences about frequencies... like 10Khz or 12Khz or 14Khz cause some models are intended for nugget hunting (TGS) and others like general purpose (e.g. bandidoII).

All about same power... same voltage peak-peak at TX so ... similar performances. Tesoro's shine about disc, at least for standard models depth is average... but in optimized ones like custom TGS etc. you can get a top of the range VLF at the price of maybe 30eur of components and some spare time, as you already know.

Kind regards,
Max

[tiktak]

Hi,

No,
My ideal was other.
But anyway thatmk you did answer to my question.
But Royal Sabre should be more advanced then TGS.Unless from name.
Will explain you my idea next time.

[Max]

No,
My ideal was other.
But anyway thatmk you did answer to my question.
But Royal Sabre should be more advanced then TGS.Unless from name.
Will explain you my idea next time.

Hi,
yes I understand you... it has some features more... but I don't think it will go deeper than conventional cloned TGS cause tx stage is similar and other parts too...

I think instead LOBO is more interesting thing but problem is that is complex and results will be always in the depth range of other tesoro's.

What's actually make the difference are:
-tx power , more power more depth (if not overload rx)
-high SNR

If you find a good compromise you'll get a top of the range VLF like modded TGS.

Kind regards,
Max

[tiktak]

Hi,

Hi,
Hah.Nice but almost inposible!
I am shore that it can go a little bit deeper.Agree?
Can we use tha audio stage from TSS to inproove TGS-s one/replace/?
So all tesoros have the same depth?
But now is 2008.There must be some idea that goes under 40cm for small coins.
p.s.how you wire coil to TGS?

[Max]

Hi,
Hah.Nice but almost inposible!
I am shore that it can go a little bit deeper.Agree?
Can we use tha audio stage from TSS to inproove TGS-s one/replace/?
So all tesoros have the same depth?
But now is 2008.There must be some idea that goes under 40cm for small coins.
p.s.how you wire coil to TGS?

Hi,
I wired in the way it disc stuff... I already explained some (many) posts ago: if you reverse leads you lose good discrimination.

A little deeper ? Maybe but it's worth a try and all the work required for just some 2-3% more if it that way ? I think not... cause if you made wrong shield you'll lose more 5-8% depth and more... so it's not so great stuff to gain. Better making good/better coils on TGS if so.

All tesoro don't have same depth... some are PI detectors so are different; some are computerized versions like tejon or cortes with MCU stuff and visual ID and some have not sinusoidal TX.

No they aren't all the same... but old uMax series is made of all similar detectors... golden sabre is similar in performance to silver... silver to bandido... compadre is less sensitive than bandido but how much ... 2 inches maybe ? Not big differences ... maybe maximum gap is around 2 inches from top of the range to lower end detector like compadre.

Some have multichannels (4 instead of 2 etc) but depth is about the same.

"But now is 2008.There must be some idea that goes under 40cm for small coins."

yes , sure... but the problem is exponential decay of magnetic params... and noise/ground signals that mask targets... so reducing SNR for stuff buried deep. There's no revolutionary VLF detector at Tesoro (and same for other companies) cause they just made them digital but performances of today are about the same of 10 years ago... and vs some models of also 20-30years ago (like old GOOD VLF/IB/BFO) they LOSE, still today !

What's good in TGS modding is that you can tweak it to the limit and gain the hall of fame of your detectors experience if you are skilled enough and have time to invest...

The only good solution to go deeper than VLFs is using PI but you will lose discrimination or have unreliable one... that's a BIG (I will say ENORMOUS) price for some extra inches depth.

Also... PI are not good in some places... where just VLFs could operate good way, even if at less depth than a PI on air there ! Belive me... I tested many of them with catastrophic results... even the more expensive designs... NO WAY. Be aware of pottery, ceramics, fired bricks etc when using them... NO WAY! Just VLFs are GOOD in pottery hell!

So... don't ask for deeper stuff that has too reliable disc... simply there isn't at now using small power like tesoro's. You can think at nexus and similar if wanna gain depth but who has schematic or coil details ?

Maybe next generation of PIs will solve this better than putting hi tx power out on VLFs... I hope so.

Kind regards,
Max

[tiktak]

Hi,

Hi,
I belive you Max and I am fully agre with you.But the top layer of leaves is 12-25 cm. so when you add level diferances,stones, etc. and keep in mind that there were 100 people before you there digging for hours every signall!
You get my point.
I dont even looked at PI.I now its no good.
But I am shore that VLF can go deeper,just need new Idea!!!!!
For nexus dont be worry.I think its not so good as stated.
Many different upinions.
And I cant belive that no one have copyed nexus.
See you

[tiktak]

Hi,

Hi,
Max I think that we miss something with ower DDs.
Ivconic have done his work perfrct calculating this coil,
but he starts from nothing.I mean no data at all.
So can there be comp.winding in quality DDs?

[Qiaozhi]

Hi Qiaozhi and Max,

Your explain is very good, but in my test it's very strange.Today i test the TGS,I find that just like Max had post in page 57,The GEB channel is sampled at the peak point,the GBE is good.
乔治，I find that i set the GEB channel sampled at the zero-crossing point,the GEB can't work at all.I test in the loess soil.
Max i also use a ferrite pole to test,i find it can also makes phase shift in the Rx coil.I set the GEB channel sampled at the peak point,another channel sampled at the zero-crossing,the sense and the GBE were work good. but the is not at the max,loss about 8cm in deepth.
Very sorry my bad english.

Do you have an original Tesoro coil? Then you will see the correct phase relationship between the TX and RX signals. Your own homemade coil must match this setup. Please attached image, which shows the TX signal compared to the RX signal at the output of the preamp.

For nexus dont be worry.I think its not so good as stated.
Many different upinions.
And I cant belive that no one have copyed nexus.
See you

Have you even seen one in real life?
You cannot express an opinion about the Nexus until you've tested it.

[tiktak]

hi

Oh.This hurts!
Did you?

[Max]

Do you have an original Tesoro coil? Then you will see the correct phase relationship between the TX and RX signals. Your own homemade coil must match this setup. Please attached image, which shows the TX signal compared to the RX signal at the output of the preamp.


Have you even seen one in real life?
You cannot express an opinion about the Nexus until you've tested it.

Hi Qiaozhi,
yes I think this is the right answer for his questions.

Let me ask you a thing that I don't have clear ...I think I read in the patents but now these informations are vanishing from my memory...

When we made disc on VLFs we compare phase on RX channels.

I mean we take quadrature samples on received signal after preamp, 90° apart one each other and so we have then e.g. 2 channels like in TGS each with its own amplitude. Then after the amplitude on these two channels are compared (Jack Gifford's patents talk about scale factor applied and then comparision made... but it's the same stuff I think) by e.g. analog stuff like op. amps and then result is applied to comparators inputs.

This actually is like extracting from RX signal the influence due to ground and ferromagnetic , and the influence of non-ferrous and compare by amplitude thus extracting a phase information related to target.

Now the question is: which relationship exist between TX signal and RX as whole, I mean... sure exist a phase relationship that rely on target composition and influence on coil... but the quadrature demodulator action is just for giving the two ferrous/non-ferrous distinct amplitudes ?

I other terms... if I wanna disc stuff cannot I just look at absolute phase between tx and rx signal (like you showed in picture, just coil phase in air there) or I need absolutely the 2 channels ???

The question is maybe a bit stupid... cause I understand that we need the two channels cause we wanna cancel out ground signal... but , in the case I wanna disc stuff just on air, isn't enough having just a look at phase between tx and rx signal ?

I made all these thoughts cause of the Ivconic's circuit about phase shift measure... that will be cool (if works good) to tune coils phase and also to disc stuff at least "on air"... to see if detector is working good or not.

Kind regards,
Max