TESORO GOLDEN SABRE

[simonbaker]

The last modification TGSL.Air test:gold ring 40cm in the air,and is very stable.Regards.

Hi eduardo1979:

Is this zip of your layout file password protected?

Somehow I missed the memo.

-SB

[habitbraker]

I know its completly useless, but I connected my new TX coil, just to check frequency and noticed that I can detect metal objects anyway Coins at about 3cm, 10x5cm copper plate - 10cm, large iron even deeper. Something like BFO?.

I Guess that frequency changes really affect TGSL

[habitbraker]

On this page I think: http://www.geotech1.com/forums/showt...12692&page=176

[simonbaker]

I probably have 30+ hours of field use on Ivconic's version with fantastic results. I only have a few hours on this version and my only concern is stability. I actually replaced the 1M Ohm resistors with the original 470K Ohm resistors used on earlier versions, just because I can't keep it quiet on occasion. Doubling the gain on this stage is a two edged sword. I'm not saying that someone else may not have good results with this version and replacing the 1M Ohm resistors is easy. I think that I may have better results far away from electrical noise.

Also, question for Eduardo: Is the 100uF cap circled below a substitute for all the 100nF decoupling caps on Ivconic's version? (Note.. Decoupling caps are not pictured on any of the schematics but are evident on Ivconic's TGSL PCB version). There is a reason for using 100nF decoupling caps, especially for the LM308s. Typically, smaller ceramics do a better job of filtering noise over the electrolytics, at least that is what I have read. I'm just looking for justification on leaving off the 100nF caps.

As far as the audio section, this is the way to go to drive an speaker!

Silverdog, I'm working on documentation at the moment. I need to get more than just a "read only" version of Adobe!!

I'm lost in the weeds -- is there a Sprint PCB layout file for the latest eduardo version (fixed audio capacitor ground, replace 100uF bypasses with 100nF) somewhere we can download? And was a complete schematic ever posted?

Regards,

-SB

[Qiaozhi]

My null phase is different - about -40deg (lagging TX)
On this second coil I didnt ground RX and didnt connect hichiker wire. (I red your exp with wet grass)

In few days I will report how it works

This is possibly he reason why the null phase is different.

[habitbraker]

I don't think so. Here is the way that mine works:

With the GB pot in the full CCW position AND in the all metal mode, ferrite will respond with positive signal. Advancing the GB pot CW, there should be a point where ferrite goes quiet, somewhere around the mid range setting. Advancing maybe another 10 to 15 degrees, ferrite will again be detect, but you will now get a negative response, meaning that you will get a signal from ferrite at some time after it has passed the coil.

Also, switching to the DISC mode, silver will no longer respond if you advance the GB pot too far past the point where ferrite is rejected.

If this is not the case, then maybe your phasing is off.
Don

Do you have a way to check your null phase?
http://174.132.129.189/~moreland/forums/showthread.php?t=16122&page=21

thanks! It is exactly like you described with my first coil - a small area of GB pot (about at middle), where ferrite is rejected, but silver is accepted only on on eside of that turning area. That I understand.
But this second coil...
In spite of that sensivity is great as well as disc.

I potted it anyway to check how it works on field.
My null phase is different - about -40deg (lagging TX)
On this second coil I didnt ground RX and didnt connect hichiker wire. (I red your exp with wet grass)

In few days I will report how it works

[dfbowers]

Hello!
I made new coil and got one interesting thing: is this normal that I can reject ferrite on all GEB trimmer settings? Ok, silver is not detectable on all settings...

I don't think so. Here is the way that mine works:

With the GB pot in the full CCW position AND in the all metal mode, ferrite will respond with positive signal. Advancing the GB pot CW, there should be a point where ferrite goes quiet, somewhere around the mid range setting. Advancing maybe another 10 to 15 degrees, ferrite will again be detect, but you will now get a negative response, meaning that you will get a signal from ferrite at some time after it has passed the coil.

Also, switching to the DISC mode, silver will no longer respond if you advance the GB pot too far past the point where ferrite is rejected.

If this is not the case, then maybe your phasing is off.
Don

Do you have a way to check your null phase?

http://174.132.129.189/~moreland/forums/showthread.php?t=16122&page=21

[ApBerg]

Yes, this is almost normal, look at the start.. post no. 15... long ago....
At some point ferrit give,s an echo sound ?! . Look for the point that is silence for ferrite and give's good sens. for large silver !
As I remember the 15 pF cap is te one to look at if the adjustment is not o.k.
Best regards.

Ap

Hello!
I made new coil and got one interesting thing: is this normal that I can reject ferrite on all GEB trimmer settings? Ok, silver is not detectable on all settings...

[habitbraker]

Hello!
I made new coil and got one interesting thing: is this normal that I can reject ferrite on all GEB trimmer settings? Ok, silver is not detectable on all settings...

[mollax]

TGS proteus

[simonbaker]

Hi Don ,

Please feel free to use anything you want including the videos , I'm not intending to remove them ever .

If you want send me the final schema / diagram Simon (?) ever made for the TGSL with the points marked from which you want a graph or video or both even in rest or with target signal !
Just like the 'TGScompare' document.

Can't give any guarantee in time but I will make them for you .

Wanted to do that for my little 'TGS for Dummies" project but crashed on some places so took more time as expected , was busy to convert the pcb layouts and schematic of the TGS to the TGSL numbering...( must be out of my mind , this costs lots of lots of time )

[ATTACH]15322[/ATTACH]

allthough I have the TGS , it is ( I think) almost similar to the TGSL .

Let me know,

kind regards ,


Dennis the Mennis

Hi Dtm:

I forgot you made TGS, not TGSL -- is that correct? Or do you have both?

For TGS, that changes my understanding of some of your issues. For example, it probably is a little more important to have the 100K DISC pot instead of 10K, because there is another 10K pot in parallel. Also, C9 probably not a problem because TX wave will be smooth and smaller voltage. Also, you would expect less air depth because smaller TX signal.

Next step is to get results of your DISC mode detection - what depth, what coins used? Also, which circuit (TGS or TGSL)?!

TGSL for dummies project is ambitious, and you end up teaching yourself how it all works! Some people may want permissions for exact design for example PCB layouts I would think. I hope someday I can make a significantly modified design and my own layout of some MD and publish a book/manual also. I use lulu.com for my publishing projects.

Cheers,

-SB

[Dennis the Mennis]

Dennis, I am putting together documentation and will have "something" soon! I now have a way to put together a pdf document so I am making progress .

Once I complete a rough draft I will post it here for revision. Just one question for everyone: Do I have permission to collect some of the graphs and diagrams already posted??

Stay tuned!!

Don

Hi Don ,

Please feel free to use anything you want including the videos , I'm not intending to remove them ever .

If you want send me the final schema / diagram Simon (?) ever made for the TGSL with the points marked from which you want a graph or video or both even in rest or with target signal !
Just like the 'TGScompare' document.

Can't give any guarantee in time but I will make them for you .

Wanted to do that for my little 'TGS for Dummies" project but crashed on some places so took more time as expected , was busy to convert the pcb layouts and schematic of the TGS to the TGSL numbering...( must be out of my mind , this costs lots of lots of time )

schematic 190 Kb TIFF.TIF

allthough I have the TGS , it is ( I think) almost similar to the TGSL .

Let me know,

kind regards ,


Dennis the Mennis

[simonbaker]

Dennis, I am putting together documentation and will have "something" soon! I now have a way to put together a pdf document so I am making progress .

Once I complete a rough draft I will post it here for revision. Just one question for everyone: Do I have permission to collect some of the graphs and diagrams already posted??

Stay tuned!!

Don

Anything I posted is ok to use. I'll bet if a little credit is given no one would object.

-SB

[dfbowers]

Hi Simon ,

I will try the configuration of the horizontal axis when my laptop is back from the ICT department again ...
The time scale was ( in yellow , see my other pictures ) printed under the grid untill I had a software update for my USB scope due to problems with external triggering , got this problem back ...
These were the first pictures I've posted after the update and I didn't notice the missing scale , good observation.

Yes , there is a possibility to add text to the bottom of the graphs but it isn't displayed , or at least not when I save it as a GIF file , didn't try the other 'save as' options yet .





It looks similar to the one of Habitbraker so I must be close ...
I didn't spend that much time at the DISC mode in the past because I was a little focused on the ' All Metal ' mode : Why do I get good detection and some time later absolute worse detection . ( In my case really unpredictable noise , some more postings about that later for anyones benefit)
And I had a defect in that part of the circuit so it wouldn't work ever ...
I will do some more experimenting with different materials.




I removed C9 and connected an IC socket as a kind of brigde were I can easily place or remove caps .
I will post some more graphs with different values for C9




Please let me know if want to do some other 'blob' testing.

And you're welcome , yes it takes a lot time making all the graphs and videos ...
Just like you answering all the posts , I should also thank you Simon . ( and all the others with a helping hand )

I hope that the graphs and videos can contribute to anyone having problems or trying to troubleshoot and don't know what to expect , just like me at some points.

I hope also to bundle someday all info but that is a lot of work

[ATTACH]15310[/ATTACH]

kind regards ,

Dennis the Mennis

Dennis, I am putting together documentation and will have "something" soon! I now have a way to put together a pdf document so I am making progress .

Once I complete a rough draft I will post it here for revision. Just one question for everyone: Do I have permission to collect some of the graphs and diagrams already posted??

Stay tuned!!

Don

[simonbaker]

Hi Simon ,

I will try the configuration of the horizontal axis when my laptop is back from the ICT department again ...
The time scale was ( in yellow , see my other pictures ) printed under the grid untill I had a software update for my USB scope due to problems with external triggering , got this problem back ...
These were the first pictures I've posted after the update and I didn't notice the missing scale , good observation.

Yes , there is a possibility to add text to the bottom of the graphs but it isn't displayed , or at least not when I save it as a GIF file , didn't try the other 'save as' options yet .





It looks similar to the one of Habitbraker so I must be close ...
I didn't spend that much time at the DISC mode in the past because I was a little focused on the ' All Metal ' mode : Why do I get good detection and some time later absolute worse detection . ( In my case really unpredictable noise , some more postings about that later for anyones benefit)
And I had a defect in that part of the circuit so it wouldn't work ever ...
I will do some more experimenting with different materials.




I removed C9 and connected an IC socket as a kind of brigde were I can easily place or remove caps .
I will post some more graphs with different values for C9




Please let me know if want to do some other 'blob' testing.

And you're welcome , yes it takes a lot time making all the graphs and videos ...
Just like you answering all the posts , I should also thank you Simon . ( and all the others with a helping hand )

I hope that the graphs and videos can contribute to anyone having problems or trying to troubleshoot and don't know what to expect , just like me at some points.

I hope also to bundle someday all info but that is a lot of work

[ATTACH]15310[/ATTACH]

kind regards ,

Dennis the Mennis

All good... we'll wait for more posts with your findings using DISC mode (if it really is working) and if different C9 values help DISC mode (usually not big difference, but still useful to know).

Your book is good looking anyway! The hard part is a way to answer all the questions that get asked about the TGSL!

Cheers,

-SB