PIM-2 Digital Metal Detector Project

[volcano]

Hi Jap
Now, I have not any the signal, when I test metals.
this problem is reason of ( the resistance R16 was moving )
I weld the résistance R16 very well.
But already I have not any signal when I do the test.

[jap]

Frequent questions for PIM-2ver05 and easy board was divided into parts as schematic:-
1 - part of the coil and power.
2 - part programmed controller[atmega] + key sw1...4
3 - part LCD and control.
4 - part match between the signals used by atmega8.
5 - part audio{SP} out.
6 - part of a normal delta pulse .
-----------------------------------------------
I've put all the notes .[*]-all dEMO HEX =~ver05 used only in ver01,02,03,04,05 pcb.
-V06 used only with v06 pcb.
-atmega8 pi = atmega8 pu = atmega8a pu [any of ver will work]
-start test with coil 40cm , 3~4 ohm,400~500uh.
-Must use keyboard sw1~4.
-D12 if not =short
-all value of R Can be modified to obtain the best results.
-R3 15 k to 22 k [V05]
-R4 10 k to 12 k
-R51,53,54,55 1% [V02,,5]
-R16=2.2/5w
-C are All worked and change values for improvement.
-all C 100n is mk type.
-There are important components in the function, such as D4,D3,T9,VD3,4 ,R6,VD7.
-Most problems of choose different types of LCD and followed connection method.
-There are important components in the function, such as part4***. .
-Responsible for higher sound both T2,R9,c27.
-Responsible for the delay in the start , C2,C3,C5,c6.
-The difference in results is due to the difference in components and quality of connections of the pcb.
best time
j.

[volcano]

thank you very much Jap

look to my project

[jap]

Hi volcano
-Nice work
-change all R=4.7K.
-change all R=680 OHM.
-Test & change IRF740,TLO81,VD3,VD4,C2=1000UF/16V,C55.
best time
j.

[volcano]

Hi Jap

I test all the R, all are well

all R=4.7k and all R=680 ohm are well ( I do not change it )

I change IRF740,TLO81,C2=1000UF/16V

I have already the same problem

[jap]

OK,,,See
j.

[volcano]

ok Jap, I understand
you want to say that the quality of R=4.7 k and 680 is bad
and IRF740 hot.

So I will do all what you requested from me

thanks

[oros27]

ok jap check irf 740 bc the 337 and put a diode byv 28

[volcano]

thank you Jap and oros27

I found the error :
the resistor R44 was damaged, I changed it.
So I see the signal of the test.
But always, I have not got a good result (long depth), I think that my coil is not good.

thanks

[coccobello27]

same problem wit metal detector
i used netgear adaptor 12v 1,5A
today i was test with 3 amp.
sound missing
only when is near neon lamp
i have v3 firmware
i will update to v5 soon
Coil have 4 ohm with cat 5 cable

[coccobello27]

thank you (all)
found your informations usefull
my irf740 was damaged
i use second coil cat 5 (again 4 ohm)
need to try cat 6 cable

[coccobello27]

update to v5
same problem..
it was power on util i work in other room
battery discearged on 6v when i coming back.. the soud is apear..

[jap]

it was power on util i work in other room
..

Hi coccobello27
What do you mean works?
best time
j.

[coccobello27]

sound working but not detect
i have replace Mc14504b with cd4504be i not sure if this is my problem..

[jap]

Hi coccobello27
-read reply #197,203
best time
j.