TESORO LOBO SCHEMATICS

[FOMA]

About Layout 0.5 have answered.
I did detector ELDORADO - c round spool BANDIDO(Tx-10500Hz
Rx -11000Hz).
The Scheme did not change.
The Detector LOBO only came to do. Since do not know the parameters of the spool.

It is Correct I have drawn the spool WIDESCAN?

[ivconic]

Hi ivconic
You need install sprint layout 5 on your computer .
see PCB Freeware or shareware thread at this link
:https://www.geotech1.com/thuntings/s...ad.php?t=11458
post#14.
Regards.

Yes it is working!
Thanks AFT 72005!
Regards!

[aft_72005]

Hi ivcinic
I am happy which it is useful for you.
But I had problem with it

[Qiaozhi]

About Layout 0.5 have answered.
I did detector ELDORADO - c round spool BANDIDO(Tx-10500Hz
Rx -11000Hz).
The Scheme did not change.
The Detector LOBO only came to do. Since do not know the parameters of the spool.

It is Correct I have drawn the spool WIDESCAN?

The Tesoro 8x12 widescan coil that I have is a concentric, not an omega.
Unless you have a real desire to make your life difficult, or simply just like building coils, I would highly recommend that you buy a Tesoro coil secondhand. They are not very expensive, if you shop around. Otherwise you are in danger of having two unknowns - the home-built circuit and the home-built coil. If you really want to construct your own coil, then you can always resell the Tesoro coil later on.

Good luck!

[FOMA]

I it is necessary photography of your spool. The Geometric sizes.
The Inductance Rx and Tx. You will Be able this show on forum?
In our edge TESORO much little, and they cost much.

[FOMA]

Has Found in archive information on spool. Now, there is data:
spool Widescan 5"х10" for old LOBO
RX=155 turns (0,22mm) L=9,93 mH TX=56 turns (0,3mm) L=1,33mH
spool Widescan 8"х15" for old LOBO
RX=125 turns (0,22mm) L=10,52mH TX=44 turns (0,3mm) L=1,37mH
I seem this it is correct.

[aft_72005]

Hi FOMA
Are you know what IC we can use instead of LS204 opamp?
Regards.

[FOMA]

Hi aft 72005.

No do not know. Shall try other double amplifiers:
LF353, LM358, TL072, NE5532.

[porkluvr]

I think MC33178 is close to LS204. Quad version is MC33179 (similar to LS404).

[maxbiri]

Hi Foma

Pay attention the shematic in zip file have same error of connession and component value.
Last night i compared it whit schematic posted by Max and found same errors
1) first rx stage have reversed pin 2-3
2) two trimmer around 555 must be 2k5 and not 25k
3) 4.7 microF capacitor must be non polarized type
I found even other strange component value but now dont remenber well.
I dont check all schematic so maybe there are others errors.

Bye Max

[FOMA]

Hi maxbiri

I little has corrected the scheme.
The Detector works, but sensitivity worse than beside ELDORADO.
Is Not built from ferrite. Frequency 17,5 kHz. I =100mA.

[maxbiri]

Hi Foma

I check a little again yours schematic and found these:
1) C7 must be 10 nf not 100 nf
2) r56 must be 200 k not 100k
3) all bf 245 have S and D reversed, in may opinion, maybe it's not important because they work as swichs.
But you design pcb from this schematic and it work?
Again not check 100% of schematic.

Bye Max

[FOMA]

Hi maxbiri.

Here is my pcb.

[amtech2005]

TESORO LOBO SCHEMATICS

Hello , here is a zip file that has viewable images and the .lay file of the original lobo. This is not the newer lobo S/T that has the pic-chip for the auto-tracking circuit. But this lobo had very good field test results . I will be posting this detector circuit later on , in the "Circuit Analysis" thread........Bye..........Eugene

[maxbiri]

Hi Foma

Yours pcb look very nice but use smd components, i hate smd.
The pcb was traced from a original lobo pcb? or is designed upon schematic you posted?
I dont know sprint layout and so i'm thinking about design a new pcb using conventional components.
Do you think possible starting from yours pcb and convert it to not smd component?

Bye Max