TESORO GOLDEN SABRE

[nelson]

Good try Ivconic.

About CA3130, is possible to reduce gain to 20% to get close to LM308, cause may be you have to much gain and that make it work erratically?
This is my own curiosity and i have no idea if this is possible.

Regards

Nelson

LT1008 should be good replacement for LM308, therefore LT1012 should replace 2 of LM308 put togather in this schematic...noted as TL082....
I tested TL081 and later TL082 and those working erratic, producing to many "blah,blah..." in speaker when Sensitivity pot is over 50%.... Bad choice....
Also tested: 741,LM318,CA3130,CA3140,1458,4558,LM301,LM311,NE55 34.....
None of those can replace LM308 in this design!
Interesting was playing with CA3130; depth was much greater than with LM308....over 40%....but works erratically when no target in coil proximity???
It should be reconsidered, might CA....be used with some surrounding components changed...? I am to tired of experimenting, also have 8 Goldy pcb's to finish these days...so i let you, guys to check CA3134/40.....
Regards!

[ivconic]

Considering op-amps...

LT1008 should be good replacement for LM308, therefore LT1012 should replace 2 of LM308 put togather in this schematic...noted as TL082....
I tested TL081 and later TL082 and those working erratic, producing to many "blah,blah..." in speaker when Sensitivity pot is over 50%.... Bad choice....
Also tested: 741,LM318,CA3130,CA3140,1458,4558,LM301,LM311,NE55 34.....
None of those can replace LM308 in this design!
Interesting was playing with CA3130; depth was much greater than with LM308....over 40%....but works erratically when no target in coil proximity???
It should be reconsidered, might CA....be used with some surrounding components changed...? I am to tired of experimenting, also have 8 Goldy pcb's to finish these days...so i let you, guys to check CA3134/40.....
Regards!

[ivconic]

3

und schematik....

[ivconic]

2

Placement....

[ivconic]

Regards to VLADIMIR !!!


From "XR-71 Sniffer PI schem+PCB " thread:
"..PS. I do not know why Ivconic will not put circuit TGS on a forum which was drawn by me.
It is not necessary to ask me any sanction.
Best regards!
Vladimir D...."
Vladimir, first of all, thank you so very much for drawing this pcb for me!
I wasnt intended to spread this arround since it is not my work but yours...Only you have
full right to do that.
But since you already stated that it can be posted freely than i feel free to do that here.
So, here is one-sided,small pcb for TGS Light by Vladimir. I made 2 of those. Still not
finished. I need few more components to finish it and later perform some tests...
Already established that TL081 (in this case TL082) is not good substitution for LM308.
In this case i would use LT1012 instead TL082....It should work just fine. Only problem
is i cant find those in local shops....Searching for other replacement...

[Qiaozhi]

I say, it is good to use a coil calculator program as a starting point, but do NOT trust the results without verification.

Of course - the user must always verify the results.
However, without a coil calculator, how do you have any idea how many turns to wind for a given inductance? The CC at least gets you in the right ball park. Personally I usually manage to design coils more quickly with a CC than without.

[porkluvr]

We are not alone

Looks nice, but calculated inductance is too low.

All so-called inductance calculators are inaccurate. No matter how well the code may be written, no matter -all the bells and whistles, plus the best user interface imaginable; they are ALL based on inaccurate formulas. The formulas used are ALL inaccurate because they are ALL based on approximations. They use best guesss, at best.

At worst, a coil calculator uses a formula that was developed for a coil of vastly different geometry than the coil it is being applied to, and so the user gets a wildly inaccurate solution. Most CCs leave the user clueless as to what formula is being applied to the data being inputted.

One good thing about the DD coil, is that there is only ONE coil that needs calculated. With some of the other IB coils, such as "concentric", or "widescan" (very similar to each other except for their symmetry - but perhaps I over simplify), there are TWO different coils which need be considered. Additionally, there is a "negative mutual inductance" term, which involves an unknown quantity called coefficient of coupling; the "k" factor. Fortunately, the "negative mutual inductance" term is not so great in proportion to the other inductances, but there are three to consider instead of just one.

So, if you like the DD coil you are lucky, because, despite its odd shape, the computation of the DD inductance is less complicated than the computation of other IB coils.

I say, it is good to use a coil calculator program as a starting point, but do NOT trust the results without verification.

[Qiaozhi]

Hi,
the best coil calculator I found is this.

It's good to find inductance... test and see with your eyes.

But have its lacks... it find about the right inductance but other parameters are missing... just easy to add to the program so I think authors want keep it simple but that way why not include e.g. a resistance indication too ?

Mistery !

Kind regards,
Max

Looks nice, but calculated inductance is too low.

[ivconic]

???

Porkluvr...not You but calculators! I never used any "name-calling" on any member here. We must respect each other.....You missunderstood me.
Best regards!

Yes, calculators are here to help us to have some starting point of thinking....I do not use those.....There is simple equation for LC coil to calculate L or C according to wanted frequency.....I learned that in school 20 and more years ago....Who need calculators?

Besides you must not rely on calculator cose there are some differences when calculating coils for RF and other like chokes and simillar...Up to some size those calculators are accurate...Over some size are NOT! Need some extra calculations to involve if want exact result to gain....
I dont have time here to talk more detailed, but i am sure you can find all on internet....Just look for some radio-amateur link...homebrews and simillar...
ARRL boooks, literatire...
Those things are learned in schools as fundamentals...You cant get it on the fly...

[dino]

Ok Thank's Ivconic for help on this. Ill try to make something out of it and we will see the results.

Best regards Dino

[Max]

I meant in the inductance calculation pane! Damn !

[Max]

Hi,
the best coil calculator I found is this.

It's good to find inductance... test and see with your eyes.

But have its lacks... it find about the right inductance but other parameters are missing... just easy to add to the program so I think authors want keep it simple but that way why not include e.g. a resistance indication too ?

Mistery !

Kind regards,
Max

[Max]

calculators...

Hi,
calculators are good for simple e.g. round coils and effective if program takes into account variables and doesn't use just one formula.

I've tested many... no-one-sinlge-time one of these revealed to be useful on made calculation of e.g. DD coils cause shape is out of their expected ideal round-coil...

But when round coils are needed they are useful at least to have an idea of how many turns one need etc.

The trick of calculating the inside area of a D shape coil not often gives at the end the desired precision we need... so in that cases is better make some hand calculations and round-up the number of turns... then experiment till one reach the desired result.

Till now I never saw any real general purpose calculator that take into account e.g. coil shape... so that could be used directly to get values we need.

Kind regards,
Max

[porkluvr]

bark

Forget calculators....schmukctors! Work!

Work is a dirty word. Who told you I was a schmucktor?

[nelson]

Hi Ivconic, yes you are right, i miss that.
Thanks

Nelson

No Nelson, 255x137mm are dimensions only for one "D" you have to make...Not both togather!


Quiaozhi, aint no calculator solved me neither one coil so far. All those are pure theoretical....As old radioamateur i can swear on this!

Regards!