If this is your first visit, be sure to
check out the FAQ by clicking the
link above. You may have to register
before you can post: click the register link above to proceed. To start viewing messages,
select the forum that you want to visit from the selection below.
Hi ApBerg. Have you measured the inductance and resistance of your coils. Alexismex recommended that 450uH inductance and resistance 1R5. Geotech Forums provides other information coil 8" 545uH 1.24ohms http://www.geotech1.com/cgi-bin/page...oils/index.dat You damping resistor is not 330R. On the first PCB is a 402R on the second PCB is a 19R?
First , I believe you and Alex that you can hear different in audio response, there are more people that say they can hear the different in audio response . I made only some air test indoors using some different coils and damping resistors to get the best sensitivity but perhaps not the good combination …( had have mentioned that…) Now busy with some unwilling logger …. if I have that thing running I will give it a tray to make the coil/resistor combination you told . But for the results so far I think that the Baracuda is a very nice detector that, when you have learned it by experiments outdoors, will give very good results !
Test object was a medium-size goldring, coil 20 cm. Fet used IRF9640 and used 390R
Pcb board from ......... ........make a guess
For tune potentiometer 22k can be used .. For the 2N2222 you have to check the E/B/C connections ! I use Metal version instead Plastic one's think the connections are 180 deg. turned.
The text markings on the board ( and sprint layout file ) are good.
Best regards.
It can be that there is a problem with the ICL 7660... it can only go to 10.5 volt ?
In the baracuda schematic it is connected to the +batt so it can give problems if there is more than 10.5 volt connected ?
Thanks Leon for warning !
The pcb are from ...Silverdog... but before release he first wants to know if there are no errors in it !
I mostly make my pcb's myself...part from the hobby... but the Silverdog's pcb are very nice and do not cost much...
For the SW1 button...I think it is for battery check...I have not used it so I am not sure..
Hi Appie!!! I think that the button need to adjust the sensitivity threshold. I did so .... Resistor "threshold" put in the middle position .... Closed the button .... Turned resistor "delay" in a situation where a constant audio tone passed in silence. All the more to the controller delay, I did not touch. Later you can add a "threshold" to the desired level .... Very good sensitivity to small objects made of gold (1gramm pendant and earrings 1.2 grams). Thank you so much Appie, and Alexismex! You did a great job. Sincerely.
Comment