DIY TGSL STEP BY STEP BUILDING AND TESTING

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Also, I recommend this link for you to read:http://youclickspk.blogspot.com/p/te...nents.html?m=1
Now you can get on with it, put questions and I am sure members here will help you in any way.

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Thanks for sharing your experience with this chemical transfer method. I want to try it.
Yes, that is the document.
I also want you to watch a video on YouTube.
TGSL metal detector:https://m.youtube.com/watch?v=XnrStRklcUQ&t=770s

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Third, you do not have to put shielding at this stage of testing. You can leave this for later on when you are doing the final testing before potting the coil.
All you are interested in at this stage is getting the circuit working.

[chuubaba]

Chemical transfer experience was good. I used home printer papers, mixed ordinary petrol from my bike with ordinary methylated spirit and olive oil (it did not fully dissolve) in prescribed ratio. I could not wait drying so i used hot iron to press for 20 seconds. This produced strong adhesion. I soaked the board in 30*C water (its 40*C+ here) for 3 minutes and scrapped the wet paper off with toothbrush. The toner was baked to beautiful blue and looked so nice on yellow copper board. I used ferric chloride to complete the procedure of making. I attempted same transfer method for silkscreen but it did not workout well as expected.

...........You used method of chemical transfer of print onto copper board, yes? Can you say how your experience was with this method.

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Second, I would like you to read the ENTIRE build document, from the beginning. Making notes and writing down whatever questions you have.
This will help you with setting up your detector.
It is just few pages.

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Firstly, capacitors are having a voltage rating. All this means is that you must use at least the minimum that is recommended for the caps on the part/components list. You can go higher, but not lower. So if parts list says 220uf@25V, you can put 220uf@25V and above. So 220uf@35V is also good. Anything above 25volts, but not below. Got it?

[chuubaba]

Is this the build document ?

........... Do you have the Build document?.....................................

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Now that's what I'm talking about! Great job Chu! You did work very hard In short time to redo the whole thing.
If you have beep, then the circuit is good.
The only thing left is to put proper coil and tune everything.
But before you do this, here are a few things to know in general.

[chuubaba]

My TGSL is based on apberg's single side version. I am now using c3, c28 as 220uf 25v instead of 220uf 35v. After i attached a makeshift coil it is giving a beep if i attach any pot wire or oscilloscope probes. Mostly it is beeping very faint. I can see the Tx wave change with hovering of metal objects or movement of Tx coil (time/div knob set at 20uS; Volt per div knob at 1V. The voltage on Tx coil are 7.35v; same knob position as Tx. There are some milliVolts on Rx. The voltage on pin 4 of lm358 is -6.42v. Ground balance pot makes sound on connection and works towards one end of the the pot turn. The discrimination switch, sensitivity, discrimination pots sound on connection but nothing translates on scope.

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I have soldered 100nf ceramic already. How serious is it if a fault?

This is not prevent detector from working, you can change them whenever, maybe go ahead and change them, but is not the reason your circuit is not working.
You have to make a list of steps to go through. you can find everything in the Build document. Do you have the Build document?
If you do not put pics of your new pcb BACK AND FRONT, it is unlikely that anyone would been keen on assisting.

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chuubaba
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The tx coil is part of the oscillator! Hook it up!
The rx coil is part of the receiver! Hook it up!
You say you haven't made the DD coil set? Do it now!
How many times does the above have to be said?
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Do you know how to trace a signal step by step through a schematic?
Use your scope to diagnose problems, not your ears.
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I'm not convinced you're not a troll.
Just buy a detector.

Chu, you must allay the troll talk by putting picture of your NEW pcb. Do not let such an allegation stand against you or people will begin to have doubts.
You used method of chemical transfer of print onto copper board, yes? Can you say how your experience was with this method.

[kt315]

Fixed. Thank you for quick remedy. Why it is silent when every component and joint i fixed is more than perfect??

look on schematic. no TX coil - no generation. no generation - no negative voltage.
if you choiced schematic you must see all problems.

[rickb]

chuubaba
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The tx coil is part of the oscillator! Hook it up!
The rx coil is part of the receiver! Hook it up!
You say you haven't made the DD coil set? Do it now!
How many times does the above have to be said?
\
Do you know how to trace a signal step by step through a schematic?
Use your scope to diagnose problems, not your ears.
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I'm not convinced you're not a troll.
Just buy a detector.

[Hyena]

Fixed. Thank you for quick remedy. Why it is silent when every component and joint i fixed is more than perfect??

I guess its because your fix is far from perfect Dont know.
Change caps to 100pF and send photos of your PCB both sides in high resolution. Also coil... Then we can use our witch crystal ball more preciousely

[chuubaba]

I have soldered 100nf ceramic already. How serious is it if a fault?

Typo: it should be 100pF