TGSL Tuning & troubleshooting

[johnsmith77]

IGSL Forum.
But we can send him personal messages also.....
Regards
Andy

IGSL Forum, yes. Any others, not geotech1.com?

[der_fisherman]

IGSL Forum, yes. Any others, not geotech1.com?

Ivconic always signed with his personal email address if I remember correctly.....we must just find of his posts!!

[salih]

What happens to me on my tgsl

hello 2 any 1
I tested my TGSL in air 2.2cm coin I get in 30cm
I tested it in really World in Two types of soil I get only 10cm On the ground
((same coin 2.2cm Of course ))
Do I have a problem in PCB or on IC,Tr,C,R or TGSL the problem cant fined deep coin???????
If I am wrong TGSL so good Very Sensitive ! which PCB is good and you can hear Strong sound and good sensitive which 1 Many PCB for TGSL???????????
Please These questions For any 1 Try TGSL in SOIL in really World not in air ( what PCB and what the Results for coin deep in ground ) help
Greetings

[johnsmith77]

hello 2 any 1
I tested my TGSL in air 2.2cm coin I get in 30cm
I tested it in really World in Two types of soil I get only 10cm On the ground
((same coin 2.2cm Of course ))
Do I have a problem in PCB or on IC,Tr,C,R or TGSL the problem cant fined deep coin???????
If I am wrong TGSL so good Very Sensitive ! which PCB is good and you can hear Strong sound and good sensitive which 1 Many PCB for TGSL???????????
Please These questions For any 1 Try TGSL in SOIL in really World not in air ( what PCB and what the Results for coin deep in ground ) help
Greetings

Hello,

Some information will help.
Can you tell on what type of ground you are testing? I mean soil.
Did you try trim GB pot (trimmer) in field?

[salih]

Hello,

Some information will help.
Can you tell on what type of ground you are testing? I mean soil.
Did you try trim GB pot (trimmer) in field?

hello johnsmith77
the frist soil is sand the second one is a Clay soil and yes I search for best GB
regards

[salih]

HELP

[simonbaker]

hello 2 any 1
I tested my TGSL in air 2.2cm coin I get in 30cm
I tested it in really World in Two types of soil I get only 10cm On the ground
((same coin 2.2cm Of course ))
Do I have a problem in PCB or on IC,Tr,C,R or TGSL the problem cant fined deep coin???????
If I am wrong TGSL so good Very Sensitive ! which PCB is good and you can hear Strong sound and good sensitive which 1 Many PCB for TGSL???????????
Please These questions For any 1 Try TGSL in SOIL in really World not in air ( what PCB and what the Results for coin deep in ground ) help
Greetings

All the TGSL PCBs are capable of 30 cm in the air.

Is the coin 10 cm below the soil, or are you testing with coin on top of the soil?

-SB

[salih]

All the TGSL PCBs are capable of 30 cm in the air.

Is the coin 10 cm below the soil, or are you testing with coin on top of the soil?

-SB

hello
Are you experienced Tgsl in The field if you do what Results you get in deep in ground for 1E
Greetings

[salih]

help
ello 2 any 1
I tested my TGSL in air 2.2cm coin I get in 30cm
I tested it in really World in Two types of soil I get only 10cm On the ground
((same coin 2.2cm Of course ))
Do I have a problem in PCB or on IC,Tr,C,R or TGSL the problem cant fined deep coin???????
If I am wrong TGSL so good Very Sensitive ! which PCB is good and you can hear Strong sound and good sensitive which 1 Many PCB for TGSL???????????
Please These questions For any 1 Try TGSL in SOIL in really World not in air ( what PCB and what the Results for coin deep in ground ) help
HELP
Greetings

[johnsmith77]

help
ello 2 any 1
I tested my TGSL in air 2.2cm coin I get in 30cm
I tested it in really World in Two types of soil I get only 10cm On the ground
((same coin 2.2cm Of course ))
Do I have a problem in PCB or on IC,Tr,C,R or TGSL the problem cant fined deep coin???????
If I am wrong TGSL so good Very Sensitive ! which PCB is good and you can hear Strong sound and good sensitive which 1 Many PCB for TGSL???????????
Please These questions For any 1 Try TGSL in SOIL in really World not in air ( what PCB and what the Results for coin deep in ground ) help
HELP
Greetings

Yesterday i was first time with my TGSL outside. Found bottle caps, handy knife, coin I did not performed the depth test, too cold wether and too happy testing TGSL.
I remember posts by Ivconic and others, it should be about 25-35cm in soil depending on coil size.
Can you reject ferrite and iron totally?

[Jerry]

help
ello 2 any 1
I tested my TGSL in air 2.2cm coin I get in 30cm
I tested it in really World in Two types of soil I get only 10cm On the ground
((same coin 2.2cm Of course ))
Do I have a problem in PCB or on IC,Tr,C,R or TGSL the problem cant fined deep coin???????
If I am wrong TGSL so good Very Sensitive ! which PCB is good and you can hear Strong sound and good sensitive which 1 Many PCB for TGSL???????????
Please These questions For any 1 Try TGSL in SOIL in really World not in air ( what PCB and what the Results for coin deep in ground ) help
HELP
Greetings

From your description, it seems your TGSL is working pretty good. Thirty CM in air is a good bench test. I would use it a bit to familiarize yourself with the detector and also tweak the ground balance and Disc settings. There can be a variety of reasons why you test in the ground was only 10 cm.

I was messing around with a commercial detector last month and was having problems finding U.S. quarters at about 10 cm. However this was right in my yard. I know for fact that this detector goes much deeper because I have found many things 25 to 30 cm deep with it. Two days ago I dug a silver dime 15 cm deep at a foot ball field. Same detector that I had problems finding stuff 10 cm or less in my yard.

So I would work with it for a while actually hunting and see how it goes, You may be surprised at how well it works.

Best of luck

Jerry

[simonbaker]

Hello,

I managed my TGLS work good. As i think

Reason: U105 pin 4 was not connected because break in pcb.

But even working with one channel TGSL managed detect 1 euro 29cm-30cm in disc mode. reject ferrite in am mode. Not reject ferrite in disc mode.
But tr4, tr5 drain signal polarites are the same as previously.
Disc works good for now.

I had constand sound on all distance before finding error. Now-not. I decided make 555 delay. But before i will make it i made experiment. I put swith between that pcb braked trace. At first i use it swithced off. So in real conditions i have strong signal on metal object. Then connect switch on. Using this i have weaker sound, can measure depth by sound strenght and have discrimination

That is very funny. By mistake you invented a useful mod! But pin 4 is the V- I think, so maybe not a reliable way to do it, but it gives a useful idea. I suspect that somehow the output of U105 is high all the time with pin4 disconnected giving you a single channel MD. I would need to check with oscilloscope to understand fully.

It also shows that maybe a single channel TGSL (TGSL/2?) might be a nice easy circuit to have fun with. Could probably make a pinpointer, or MD for children. (we don't need no stinkin ground balance...)

1) Problem with bottle caps. How it solve?

I think rusty bottle caps are very difficult to discriminate, for most MDs.

a) use cc coild insted dd? (found this on internet)

Sure, orginal TGS used concentric coil. Search TGSL thread.

2) Can you recommend best md that rejects bottle caps good?

Someone else can help you better with that question.

3) I installed metal socket on my coil. I see it rised nulling voltage. It affect nulling voltage depending on place it is installed. Do you know place where to install that socket on coil where null voltage would be affect at least. I noticed it very affect if installed on corners.

You need to experiment somehow to determine best place. It may not hurt your detection as much as you worry.

4) I can achieve at least null voltage on pin 7 LF353 1Vpp (when pin 5 grounded = when not grounded. (Pin 5 grounding i found in Dfbower's manual.)
I can achieve at least null voltage on pin 7LF353 0.4Vpp (when pin 6 grounded). (Pin 6 grounding i found in Ivconic's manual)

Is my voltages too big?

No, those voltages sound typical to me and do not mean something is wrong.

5) I see people discussing about 1-10mvpp nulling voltage. But on oscilograms uploaded to this forum i see ~0.6Vpp.
Why so difference? Do i understand it wrong?

I think those small voltages are measured directly at coil leads using AC voltmeter, not at LF353 pin7 with oscilloscope.

AC voltmeter often measures lower voltage because of limited frequency band.

Thank you!
Best Regards

Regards,

-SB

[johnsmith77]

(we don't need no stinkin ground balance...)

U105 pin 4 not connected to -6V. Gb channel off.

But in AM mode, GB trim still affect ferrite rejection distance, because in AM mode, both channels after Tr4, Tr5 are driven by U102B.

[simonbaker]

U105 pin 4 not connected to -6V. Gb channel off.

But in AM mode, GB trim still affect ferrite rejection distance, because in AM mode, both channels after Tr4, Tr5 are driven by U102B.

Yes you are correct -- but if U105 output is stuck high, then only DISC channel matters. I don't know what really happens when pin 4 is disconnected. Can you measure DC voltage at U105 pin 6 when pin 4 is disconnected?

The other possibility is that U105 still operates somewhat with pin 4 disconnected, but not sure how.

-SB

[johnsmith77]

Yes you are correct -- but if U105 output is stuck high, then only DISC channel matters. I don't know what really happens when pin 4 is disconnected. Can you measure DC voltage at U105 pin 6 when pin 4 is disconnected?

The other possibility is that U105 still operates somewhat with pin 4 disconnected, but not sure how.

-SB

If i correctly remember it is ~ +6V.

Also just for info: when i installed metal socket on coil enclosure, it raised null voltage 0,4Vpp. I had the same socket while testing and it was horizontal, now it stands vertical. I was shocked at first