Building Wolf Treasure [Tesoro Lobo]

[dom44]

all the info i have is from the ebay listing he gives a lot god good info, your GB prob to do with phasing issue also check the amplitude pot of transmit signal can cause problem s if not set right, also the null point on the coil is critical on mine threshold wont work if not set right.

https://www.ebay.com.au/itm/184122294712?hash=item2ade8b41b8:g:7pEAAOSw1r5bW2U6

[Ruben2000]

I can't get the GB to work. It could probably be because of the inductances of the coils.

[Ruben2000]

i set mine up for exactly 20khz on the transmit coil so will set the receive coil for 20.6khz i wound my own coils so was easy, I have 1.43mh on the Tx and 9.68mh on the Rx and i have 47n cap on Tx
I am starting with 10n on C7 as i said i have not finished with the final setup but so far has exhalant sensitivity with an un tuned receive coil. there is an LT spice simulation some one posted here a few years back on the lobo front end so you can play with part values.

Could you publish the scheme on which you are basing to be able to compare with mine?

[dom44]

i set mine up for exactly 20khz on the transmit coil so will set the receive coil for 20.6khz i wound my own coils so was easy, I have 1.43mh on the Tx and 9.68mh on the Rx and i have 47n cap on Tx
I am starting with 10n on C7 as i said i have not finished with the final setup but so far has exhalant sensitivity with an un tuned receive coil. there is an LT spice simulation some one posted here a few years back on the lobo front end so you can play with part values.

[Ruben2000]

I am working on this detector my self still at the setting up stage works great so far, I need to try with the resonant receive coil with 600hz spacing between transmit and receive coil for correct phasing.

Hello dom44.
Are you running it at 17500Hz and 18100Hz?
What capacitor do you use in C7?

[Emersonpaz]

Hello friends I am wondering why leave this 600Hz spacing between TX and RX? Why can't they be at the same frequency?

[dom44]

I am working on this detector my self still at the setting up stage works great so far, I need to try with the resonant receive coil with 600hz spacing between transmit and receive coil for correct phasing.

[Carl-NC]

i think connections of those resistors are mistake.

Probably not, they bootstrap the on/off logic levels to the analog signal.

[kt315]

i think connections of those resistors are mistake.

[Op04]

Thanks for the link op04 !!
I had read it before, I don't know if Max was able to get Lobo to work properly.
There are various Lobo schematics all over the web, but so far I haven't seen anyone posting all the correct information about Lobo.

Dear Ruben,
My point on that link is Mr.Tchoci progress, he reveals his made with different coil and components also PCB error correction. There also Legaucho work on lobo with working PCB of began this page

[Ruben2000]

how i see this sch... you have to get CLEAR symmetric signal on output of 555... to get then sinusoidal voltage
on the coil without a distortion and harmonics...
we call sometimes this signal "meander"... in last redaction, TROY SHADOW X5 i mean,
the author input a trigger after 555... it gives sure clear meander.
try to tune now...

Hi KT,
You mean there must be a 50% high and 50% low signal at the output of the 555 and no interference?

[Ruben2000]

Hi Ruben,
You must see this GoodLuck with your project!

Thanks for the link op04 !!
I had read it before, I don't know if Max was able to get Lobo to work properly.
There are various Lobo schematics all over the web, but so far I haven't seen anyone posting all the correct information about Lobo.

[Op04]

Hi Ruben,
You must see this GoodLuck with your project!

[kt315]

how i see this sch... you have to get CLEAR symmetric signal on output of 555... to get then sinusoidal voltage
on the coil without a distortion and harmonics...
we call sometimes this signal "meander"... in last redaction, TROY SHADOW X5 i mean,
the author input a trigger after 555... it gives sure clear meander.
try to tune now...

[Ruben2000]

Will the waveforms be okay?