TGSL Experiments

[simonbaker]

thank you simon for answering my question ill watch this topic with intrest
going off topic this is what i am trying to build at moment bandido 11 umax http://www.geotech1.com/forums/showthread.php?t=15725 on strip board

I'll be interested in what you do and learn. Bandido is more difficult than TGSL people say, but they all are challenge to make work excellently.

Regards,

-SB

[WM6]

I'm very interested in "stripboard" and perfboard type layouts.

My goal is to make a version of TGSL that can be made completely with parts bought at store, no customized PCB, no chemicals, etc. I do not expect it to work as well as PCB, but hopefully quite well anyway.

-SB

I like your ecological idea. Very innovative.

For simple circuit like power supply, one chip solutions etc. I also often use quick handmade proto-board made from hard transparency foil with hole "drilled" simply by awl. Not so for detector yet, cause detector pcb require rigidity without pcb oscillations.

Transparency pcb in rigid form can be made from transparency printer/copier foil (for pcb print) and acrylic glass plate according your procedure and driled as usual.

[simonbaker]

I like your ecological idea. Very innovative.

For simple circuit like power supply, one chip solutions etc. I also often use quick handmade proto-board made from hard transparency foil with hole "drilled" simply by awl. Not so for detector yet, cause detector pcb require rigidity without pcb oscillations.

Transparency pcb in rigid form can be made from transparency printer/copier foil (for pcb print) and acrylic glass plate according your procedure and driled as usual.

What is transparency foil? I'm not familiar with that.

-SB

[WM6]

What is transparency foil? I'm not familiar with that.

-SB

Probably "film" is better English term (Folie in German):

http://www.sigel.de/LF419-Transparen...W.30061.0.html

(self-adhesive also available)!!!!

Self-adhesive Film is sticked on the supporting paper and is therefore able to use it (cut out only printed PCB) only as much as you need.

[ivconic]

Oh man! I am amazed with effort you involved in that! Wasnt it easier to make regular pcb? However, i am very curious about performances of that detector. Keep us informed here.

Regards!

[kuraja]

Hi! Simonbaker! Don't you think that those things sticking out of perfboard would create additional capacitance? Not good for example if you leave to much wire on capacitor (electrolyte one) sticking out. I know this idea is great and ecological at the same time! (i like it !!!), but damn parasitic capacitance can ruin your day! If you want to make a regular PCB board, just use some toner, print it on glossy paper (take any magazine you can find and print like an envelope), iron the thing on board, and etch with H2O2 hydrogen peroxide (9-12%)+HCL cleaning product(16-18%) sollution. All you need is a laser printer ! I guess perf boards are educational but no good for final product!
If you need help about chemistry behind it just ask. F**k ferochloride!!!
I wish you luck dude!!!

[simonbaker]

Probably "film" is better English term (Folie in German):

http://www.sigel.de/LF419-Transparen...W.30061.0.html

(self-adhesive also available)!!!!

Self-adhesive Film is sticked on the supporting paper and is therefore able to use it (cut out only printed PCB) only as much as you need.

I'm still not clear on how you use it -- can you describe more? How do you make traces?

Regards,

-SB

[WM6]

I'm still not clear on how you use it -- can you describe more? How do you make traces?

-SB

On the same way as you on your pictured procedure (by direct soldering contacts of different parts and wiring). You put self-adhesive film in printer, print pcb on it, stick self-adhesive film on acrylic plate, drilling hole according pcb print and finish by placing and soldering elements according your procedure. If you wish transparent pcb of course. There are no printed copper trace on transparent pcb, if it was misunderstanding.

[simonbaker]

On the same way as you on your pictured procedure (by direct soldering contacts of different parts and wiring). You put self-adhesive film in printer, print pcb on it, stick self-adhesive film on acrylic plate, drilling hole according pcb print and finish by placing and soldering elements according your procedure. If you wish transparent pcb of course. There are no printed copper trace on transparent pcb, if it was misunderstanding.

I get it now. Yes, instead of gluing paper -- easier to line up probably too.

Regards,

-SB

[simonbaker]

Hi! Simonbaker! Don't you think that those things sticking out of perfboard would create additional capacitance? Not good for example if you leave to much wire on capacitor (electrolyte one) sticking out. I know this idea is great and ecological at the same time! (i like it !!!), but damn parasitic capacitance can ruin your day! If you want to make a regular PCB board, just use some toner, print it on glossy paper (take any magazine you can find and print like an envelope), iron the thing on board, and etch with H2O2 hydrogen peroxide (9-12%)+HCL cleaning product(16-18%) sollution. All you need is a laser printer ! I guess perf boards are educational but no good for final product!
If you need help about chemistry behind it just ask. F**k ferochloride!!!
I wish you luck dude!!!

You can trim the leads pretty close after soldering like on PCB, and you can keep all the wires closer to board if you are more skilled than me. Especially if use perfboard with copper plated holes.

TGSL is audio frequency, at least not RF -- and after capacitor C15/C12, it is very low frequency (maybe 10 Hz) -- but then many square waves running around, so I don't know how important little lead bumps are. Also I believe dominant noise is from coil, but not sure.

No question PCB is best -- we know that -- purpose of my experiment is to see how important perfect PCB is and what other techniques are possible.

I know very little about PCB chemistry -- I'd like to do it but chemicals are big pain for me, so tell more about what you think is good, I'm interested.

Regards,

-SB

[Darko]

[quote=simonbaker;95881]

Disc pot should affect voltage on C15 (in disc mode -- no affect in "all metal" mode).

GB pot should affect voltage on C12.

If your detector is good indoors, I don't think these voltages will hurt anything when outdoors, just my opinion.

Phase of null signal affects whether positive or negative voltage on caps. Some coils you can get minimum but not phase for positive voltage. Or you can get phase for postive voltage, but not minimum null.

I believe the shielding of the coil affects the null a lot. Very conductive shield can make null phase shift, make difficult to get postive voltage on capacitors I think. But not completely sure, I'm studying coils now because of these differences.

I think best strategy is to try to get positive voltage on C12 by moving a little off the null point, but not too far. Even if voltage is between -.7v and 0 should be OK I think.

Again, if your detector is working great, I don't think it matters anything else. Your detector seems to be very good, congratulations. Interesting point about computer nearby -- I'll pay attention to that now! Wireless transmitter especially...

Regards,

-SB

With this way of coil wirements voltages are ok on c12 and c15 and it is possible to null coil in proper way, but sensitivity goes down by 2-3 cm? Disc is exelent and stabillity become slightly better. Freq for bit go higer, from 14.70 to 14.74.

[simonbaker]

[quote=Darko;96686]

With this way of coil wirements voltages are ok on c12 and c15 and it is possible to null coil in proper way, but sensitivity goes down by 2-3 cm? Disc is exelent and stabillity become slightly better. Freq for bit go higer, from 14.70 to 14.74.

Ok, please compare this to what you had before -- what did you change?

Are those values correct??? .59 mH or do you mean 5.9 mH? .7 ohm, or 7 ohm? Are you making coils with very few turns?

Are you grounding/shielding differently?

Please more description, I'm not clear what you are saying.

Regards,

-SB

[Darko]

[quote=simonbaker;96701]

Ok, please compare this to what you had before -- what did you change?

Are those values correct??? .59 mH or do you mean 5.9 mH? .7 ohm, or 7 ohm? Are you making coils with very few turns?

Are you grounding/shielding differently?

Please more description, I'm not clear what you are saying.

Regards,

-SB

Sorry for misunderstanding. All parameters are standard exept wirement of coils. TX coil is not connected to the shield in coil housing. It is working good but now I have other problem. Even connected in this way or even as stated before, both ends, TX and RX connected to the shield, when I touch coil housing with hand, sensitivity fall drasticly. Some situation with several coils??!!! I think shielding is good, cable also good..I dont know why this happens!

[simonbaker]

[quote=Darko;96702]

Sorry for misunderstanding. All parameters are standard exept wirement of coils. TX coil is not connected to the shield in coil housing. It is working good but now I have other problem. Even connected in this way or even as stated before, both ends, TX and RX connected to the shield, when I touch coil housing with hand, sensitivity fall drasticly. Some situation with several coils??!!! I think shielding is good, cable also good..I dont know why this happens!

Ivconic and Max probably answer this better.

A picture of your coil housing would be helpful.

- Does sensitivity fall as your hand comes near, or suddenly when touch coil housing?

- Are you sure you are connecting ground wire of TX to shield, not hot wire?

- Exactly what type of cable are you using?

- What thickness wire for coils. What resistance (previous values not certain).

- It is not too surprising that touching coil would reduce sensitivity, but before simple answer, I hope someone with good working TGSL will try it with theirs and see how touching housing affects sensitivity.

- It is possible touching coil housing affects null through capacitance, etc. -- maybe even deforms coil positions -- can you see any change in null on scope?

- What problem are you trying to solve by experimenting with shield connections? Less noise/chatter?

-SB

[Darko]

-A picture of your coil housing would be helpful.

It’s Bulgarian plastic housing like ivconic uses for his coils. I will attach here jpg when will make some shots.


- Does sensitivity fall as your hand comes near, or suddenly when touch coil housing?

Only when I touch housing , or cable.

- Are you sure you are connecting ground wire of TX to shield, not hot wire?

Yes, I’m sure.

- Exactly what type of cable are you using?

DIN cable, 5 wires. Tried with two similar cables.

- It is not too surprising that touching coil would reduce sensitivity, but before simple answer, I hope someone with good working TGSL will try it with theirs and see how touching housing affects sensitivity.

I know that this is normal if sensitivity falls just a little when touch coil but I’m loose 10-15 cm of sensitivity of machine!!

- It is possible touching coil housing affects null through capacitance, etc. -- maybe even deforms coil positions -- can you see any change in null on scope?

-I don’t have scope. I uses sound card scope until I noticed chatters when my PC is turned on. Now I null coils with multimeter.

- What problem are you trying to solve by experimenting with shield connections? Less noise/chatter?

I try (and success) to achieve good phase like you says that voltages on c12 and c15 must be a positive. With normal (both TX end and RX end on GND in search head) wiring I don’t have success.
Well, in both cases of coil setup I notice fall of sensitivity when touch search head housing or cable.