TESORO GOLDEN SABRE

[manurespreder]

i don't know.. i am dumb or what i can't find any cu enamelled wire within 0.27-0.28 on ebay only one i found is 0.3 is it possible that there is nothing such like 0.27 - 0.28?

[manurespreder]

thank you for you thoughts i was reading tgsl Making coil.pdf

[simonbaker]

hello there,

i am reading about coil making and there is mentioned "0.27-0.28mm with resin layer"

now i am wondering what does "resin layer" mean?
enamelled? or lacquered?

Can you point us to the reference? It sounds like a description of enameled wire, or even the process of gluing/binding a wound coil by coating with some kind of glue/resin during winding. Where did you see it?

-SB

Update: I think I know what you are referring to. I'm pretty sure it just means ordinary enameled magnet wire, or similar.

[manurespreder]

hello there,

i am reading about coil making and there is mentioned "0.27-0.28mm with resin layer"

now i am wondering what does "resin layer" mean?
enamelled? or lacquered?

[Wiltran]

TGSL Coil question

Ok Don, so it sounds as if I get the TX coil close, i could probably adjust better with cap.

Here are some pics of my TGSL, and my surf pi. These two mds worked out better than I expected Surf pi -11" on a nickel and better than that on the tgsl. I also built a DBP2010, which worked, but was a major disappointment. The first DD coil on the tgsl was a failure, I could get the coils to null good, but when I added the epoxy filler. the null was ruined! So I built a 12" concentric, following the coil instructions by Dave Emory. Everything was going great til I got to the bucking coil.ll I can say is if you have a way to wind the bucking coil on a spool that will slip over the receive coil, it will make your going easier. I had trouble getting a null adding and subtracting turns on the bucking coil. Finally I got the null close , and I tweeked the bucking coil so it nulled. I want to try another DD coil, cause I want to build another coil shell. Having the coil shells make the md a whole lot easier. Wil

[dfbowers]

Thanks for the quick reply. So then its ok to take off a half turn only and loop it back following the D shape, so the pigtails will line up at the bottom of the "D". that way I can get the freq. more exact. Eduardos version is hotter? does that mean that it would find a quarter deeper in the ground?. The sound is pretty good on the TGS, and I found if I used headphones it works the best. If there isnt any substantial improvement with Eduardo version I think I might as well build latest Ivonics (version 3 I think), and maybe add the Dbowers mod to the comparator diferential. I built the TGS, and I like it except the notch feature in actual use is confusing to me. I built a 12" concentric coil, that works good, and am now building vacuum formed coil shells thanks to information you provided in your posts!

I would not worry about 1/2 turn at all as long as your phasing is correct. Shield and cable will change your freqency too. I notice much more change if my 15nF tuning cap is off by 500pF!

I think that you could potentially find a quarter deeper in the ground with a hotter TGSL, but then you might add a lot of unnecessary noise. I find myself backing down the senstitivity anyway just to get things running smoother. Again, the ground is the limiting factor in many cases.

I would be interested in seeing your 12" concentric if you don't mind. I have been tempted to try building one too.

If your vacuum forming doesn't come out, let me know. I may be able to send you a shell.

Don

[Wiltran]

TGSL COIL QUESTION

Thanks for the quick reply. So then its ok to take off a half turn only and loop it back following the D shape, so the pigtails will line up at the bottom of the "D". that way I can get the freq. more exact. Eduardos version is hotter? does that mean that it would find a quarter deeper in the ground?. The sound is pretty good on the TGS, and I found if I used headphones it works the best. If there isnt any substantial improvement with Eduardo version I think I might as well build latest Ivonics (version 3 I think), and maybe add the Dbowers mod to the comparator diferential. I built the TGS, and I like it except the notch feature in actual use is confusing to me. I built a 12" concentric coil, that works good, and am now building vacuum formed coil shells thanks to information you provided in your posts!

[dfbowers]

I got a question for Dbowers. If you are winding a TX DD coil for TGSL, and you are less than 14.5 KHZ, - say 14.420 KHZ, do you just unwind a half a turn to make the TX resonant at 14.5, and loop the extra wire back under the foil faraday shield? or do you only use complete turns even if you go over or under the 14.5 KHZ?. also I am curious to know if the Eduardo modded TGSL design is actually a real improvement over the Ivonics TGSL?
thanks.

Yes, you can just take a few turns off to get the frequency correct. I usually do that before adding any shields, but adding the shields will change your freqency slightly again anyway . As long as you are close and can still get phasing correct you should be ok .
Eduardo's version is essentually the same, so no real difference besides increase DC gain on U103. At the same time, it make the TGSL more difficult to run smoothly. It does make for a hotter machine, if that's what you want. BUT.. in my opinion in the end, the ground is going to be the big limiting factor on depth. For all practical purposes, I pick stability.

Also, Eduardo's version seems to have a slightly better audio, but I only have one build of his version so far. Using headphones, I don't know if there is any advantage there. I'm interested in seeing how yours might come out!

[Wiltran]

TGSL Coil question

I got a question for Dbowers. If you are winding a TX DD coil for TGSL, and you are less than 14.5 KHZ, - say 14.420 KHZ, do you just unwind a half a turn to make the TX resonant at 14.5, and loop the extra wire back under the foil faraday shield? or do you only use complete turns even if you go over or under the 14.5 KHZ?. also I am curious to know if the Eduardo modded TGSL design is actually a real improvement over the Ivonics TGSL?
thanks.

[dfbowers]

Sounds good. BTW, what was the total cost to you to buy those PCBs including shipping to US?

-SB

Simon,

I think it was in the neighborhood of $50.00 but could be cheaper if parts were bought in higher quantities. Like Mouser has pricebreaks starting at quantity of 5 for most things and goes down significantly from there. I'll have to ask Silverdog what kind of deals he has been getting.

If built with TL071's instead of LM308s you can shave about $10.00 off the cost of the whole project.

More testing with Eduardo's version today. On the downside, senstitivity cannot be decrease enough in my opinion, particularly in the AM mode.. but that's inside the house.

For a 1e, distance range from 25cm min sens to 40cm max before it becomes unstable with 10" coil in disc mode. I need to box it up and take it for a hunt this week to see how it really behaves.

Don

[simonbaker]

Sure, I can post up this version. I had a bag of .1uF caps left over after this build. I don't think that they are required but certainly is one of those "best practices"!

I still need to spend some time evaluating the stability aspect of this version as there is always a trade-off. I don't know if this is something that can be simulated or we just need to test in a real life environment.

BTW. You may be able to easily mod the version that I sent you without too much trouble.

More later..

Don

Sounds good. BTW, what was the total cost to you to buy those PCBs including shipping to US?

-SB

[dfbowers]

Sure, I can post up this version. I had a bag of .1uF caps left over after this build. I don't think that they are required but certainly is one of those "best practices"!

I still need to spend some time evaluating the stability aspect of this version as there is always a trade-off. I don't know if this is something that can be simulated or we just need to test in a real life environment.

BTW. You may be able to easily mod the version that I sent you without too much trouble.

More later..

Don

[simonbaker]

I was only considering the general layout and parts differences. The schematic would be the same for the left half with the exception of a few component values, but I admit, the changes could make significant differences. I will let you know in a day or so as I will probably put it together tonight..

If I have time and get a .pdf plug in to edit the schematic I can document this version.

I think Silverdog could benefit from having matching schematics with his boards.

Hi Don:

If you have a complete correct schematic it would be great to see the whole thing. I'm not exactly sure about all the "decoupling" capacitors mentioned and their values.

I'm wondering if the slightly better audio you observe is due to the audio amp circuit or rather to the longer response due to the changed caps and resistors in the filter/amplification stages.

I think slower response versions have been long overdue for discussion - the question is, what is the "perfect" response to design for? One of the reasons I'm interested in a digital version of the TGSL is so you can "dial in" any response you want into the digital filters, for different hunting requirements and different coil sizes. It could be another knob on the controls.

-SB

[eduardo1979]

Tgsl Edu

You're welcome!

[dfbowers]

Eduardo's TGSL PCB- Update..

I have the PCB from Silverdog up and running! Right off, an improvement over the version in the "TGSL complete details". Audio is slightly longer and stronger, even with a 100 ohm resistor substituted for the 22 ohm resistor in the audio section.

Also, sensitivity adjustment is much more drastic. I can only advance it mid-way before becoming unstable. NOT using any other mods..

Detection range: For initial testing, 31cm with my 8" DD home built coil! I can't remember exactly how it tested on my other TGSL but maybe a 3cm improvement.

Will test my 10" coils sometime next week. Kudos to Eduardo!

Everyone have a good weekend!


Don