TESORO GOLDEN SABRE

[tiktak]

Hi

I have saw more that 3 fatal mistakes thanks to your advices!
So,this is the best way for me!
There is nothing more useful than expiriance!
So when you dont have it you have to ask someone who's been there already!
Thanks

Welcome!


Welcome Tiktak! Yes, mostly you are right.But first you had to register and than i to admit this! I hope cahrts will help you.
Obey charts and dont worry, in 99% substitutions will work just fine.
regards!

To nelson

Hi,
Did you test your detector?
What are the results with this changes?
Hope you acive good results!

[tiktak]

Hi

Not unregistred and not pain in the ***!Thats better.
I just wanna make as close as I can to the original.And when I read dont understand!I need someone to make it clear for me and then I understand!
Maybe you think that I am stupid,but I got more that you can imagine in my head!!!!!
And in the real world there are some substitues that cant be seen in the charts!!Thats HOW THE NEW IDEAS CAME!!!!!


UNREGISTRED is greateful for the shared information!

....


OK just for unregistered, but this is last time!

[Max]

Max Thanks,but why pain in the ***????
I told this is a site for begginers

Hi,
no problem. Don't worry no pain, just a joke.
There are plenty of information about all that stuff in the Internet but sometimes you just need some hint by other people.

Some op. amps. are now also obsolete and that makes things a bit harder but for sure , if a solution exist, a replacement can be done, we'll find here.

And beginners are, of course, welcome.

That's why this forum exist I think.

Best regards,
Max

So...


Ok Unregistered, i excess with my comments from time to time. Sorry!
I am real p... in ...
You are right, this is forum for beginners, enthusiasts, hobbysts....Sorry again!
The fact is, you should download some comparsions charts for components or some software to install. ECA or similar. No need to persistently ask similar questions, post by post.
And for the last time, you should register!

!!!!

Max Thanks,but why pain in the ***????
I told this is a site for begginers

[nelson]

Max, excellent expanation about what i m not an expert.
The only doub i still have is how to connect graphically the leads to null the coils.
I have read here that also if you dont have a scope you can get it with a multimiter. My scope is very small one, this is from radioshack and is connected to the pc, but i recognize that i m not very skilly with it.
This weekend i hope i can finally finish coils and test this golden sabre. My hopes are to work with for coinshooting and also to give a try on gold nuggets, but i know now that for gold nuggets i need a good coil. I also have to remember that this MD was build with TL081 instead of LM308, so i have to see his performance.
Ok, after i try all what you and Ivconic recomended to me , i ll tell you.
Best regards and thanks for your help.
Nelson

Hi Nelson,
you can't use resistor to get right value connected at pcb pads in a VLF. That way you lose current in your coils and add small instability due to resistor thermal variations, but most important you maybe can't get it oscillate on tx cause your impedance at coil could be wrong for stable operations.

NOTE:
You can use resistors e.g. in PIs detectors where you control the on switch by other timing circuits and so haven't a free running oscillator where the coil is a part of it; also in PI adding a series resistor to coil means cutting some current and so limiting battery drain, mosfet warming etc so in PI could be convenient having a resistor.

If you rewind with another thinner wire you have more inductance if other params remains the same, and also more resistance of winding.

As an example, do make a good DD with 22cm external diameter use that data:

wire from 0.25mm to 0.28mm external diameter ; you could use also 30AWG but but little mod on turns number are often required
I use :
TX 120 turns
RX 130 turns
resistance would be around 20 ohm , for both, or even more (22-24 ohm).

Good way to make coils is always wound about 10% more turns than extimated and then measure values reducing 1 or few turns step by step, till approaching what you need.

You could find more info about coplanar concentric in Emery's article, and info about tesoro's round conc coils on Mike's instructions (you can find in older threads about bandido and others)

You also need to null very well rx signal by moving on the overlapping area one or both coils. Use a scope, connect a 1k resistor and a capacitor like in rx stage in parallel with rx leads. You need reach under 3mV peak-to-peak, the lesser the better (I get 1mv pk-pk on my DD coil and works fine).

Having a too low resistance on e.g. tx coil in colpitts osc would mean have no oscillations at all or have with too hi distortion, so keep resistance hi enough to have good shape (perfect sinus) waves and stable operations.

Best regards,
Max

[Max]

Ok Max, i ll do so, but tell me, if i rewind a smaller wire this will affect my inductance? ¿How may turns aproximate are needed to get the correct resistance? ¿Can i use a resistor for it?
What is the reason to get resistance value higer?
In advance many thanks Max
Nelson

Hi Nelson,
you can't use resistor to get right value connected at pcb pads in a VLF. That way you lose current in your coils and add small instability due to resistor thermal variations, but most important you maybe can't get it oscillate on tx cause your impedance at coil could be wrong for stable operations.

NOTE:
You can use resistors e.g. in PIs detectors where you control the on switch by other timing circuits and so haven't a free running oscillator where the coil is a part of it; also in PI adding a series resistor to coil means cutting some current and so limiting battery drain, mosfet warming etc so in PI could be convenient having a resistor.

If you rewind with another thinner wire you have more inductance if other params remains the same, and also more resistance of winding.

As an example, do make a good DD with 22cm external diameter use that data:

wire from 0.25mm to 0.28mm external diameter ; you could use also 30AWG but but little mod on turns number are often required
I use :
TX 120 turns
RX 130 turns
resistance would be around 20 ohm , for both, or even more (22-24 ohm).

Good way to make coils is always wound about 10% more turns than extimated and then measure values reducing 1 or few turns step by step, till approaching what you need.

You could find more info about coplanar concentric in Emery's article, and info about tesoro's round conc coils on Mike's instructions (you can find in older threads about bandido and others)

You also need to null very well rx signal by moving on the overlapping area one or both coils. Use a scope, connect a 1k resistor and a capacitor like in rx stage in parallel with rx leads. You need reach under 3mV peak-to-peak, the lesser the better (I get 1mv pk-pk on my DD coil and works fine).

Having a too low resistance on e.g. tx coil in colpitts osc would mean have no oscillations at all or have with too hi distortion, so keep resistance hi enough to have good shape (perfect sinus) waves and stable operations.

Best regards,
Max

[Max]

Hi,
MAX!
Then can I use LM108 or LF151 for LM308N?
I found LF153 for LF353!Its look like its even better!With high temperature stability!
What will you advice me??
THANKS

Hi,
yes YOU CAN ! THEY ARE ! YOU WON !
1xx mean they have better specs so extended ranges. So keep them and solder that stuff before you'll change idea again!
(was a real pain )

Best regards,
Max

[nelson]

Ok Max, i ll do so, but tell me, if i rewind a smaller wire this will affect my inductance? ¿How may turns aproximate are needed to get the correct resistance? ¿Can i use a resistor for it?
What is the reason to get resistance value higer?
In advance many thanks Max
Nelson

Hi Nelson,
ivconic is right, I have original coil and I see 22.6 ohm on tx and 23.2 ohm on rx.You need to rewind with a thinner wire.

Use some 30awg or european 0.25mm diameter. Find Mike's instructions on nulling the rx coil.

Best regards,
Max

???


Unregistered, you are real pain in the *** with all those questions about op-amps!!!
Are you that imbecile and idiot that can not find any proper datas on the .net?
I never saw most stupid man than you! Pain in the ***! Million same questions!

To MAX

Hi,
MAX!
Then can I use LM108 or LF151 for LM308N?
I found LF153 for LF353!Its look like its even better!With high temperature stability!
What will you advice me??
THANKS

[Max]

Ok Ivconic, yes resistance is 12.3 ohms and i don´t know how to raice it. Should i use a resistor in series?
The low resistance, may be is for the wire diameter (to high).
I agree with you, experimenting is the clue.
Today i did`t have time to work on Golden Sabre. To much ofice work and i don`t know if tomorrow i ll have the time to do so. I m just wating next weekend to finish this MD and of course post results and expirencies with it.
Will keep on touch.
Best regards.
Nelson

Hi Nelson,
ivconic is right, I have original coil and I see 22.6 ohm on tx and 23.2 ohm on rx.You need to rewind with a thinner wire.

Use some 30awg or european 0.25mm diameter. Find Mike's instructions on nulling the rx coil.

Best regards,
Max