Completed HammerHead.

[TheUnderTaker]

Hi Mr. Carl...

I have finished my Hammerhead board as your instructions and get pulse voice from the speaker like tic tic tic tic ...

but there is no response to metal until now..

still the pulse speed as it is when get some metal close to small coil..

this is my board photo..

please tell me some tags to help me complete it ...

http://img149.imageshack.us/img149/8126/10062010295.jpg

[Carl-NC]

1. Have you carefully checked all DC voltage levels, including supplies and opamp outputs?
2. Have you calibrated the circuit according to the article?
3. Do you have an oscilloscope?

- Carl

[raff33]

hi,
good luck TheUnderTaker......

[TheUnderTaker]

Thanks Mr. Carl

1. Have you carefully checked all DC voltage levels, including supplies and opamp outputs?
   
2. Have you calibrated the circuit according to the article?
   
3. Do you have an oscilloscope?
   

- Carl

[*]Have you carefully checked all DC voltage levels, including supplies and opamp outputs?

yes every thing ok like you says in the instructions.


[*]Have you calibrated the circuit according to the article?

yes word by word.



[*]Do you have an oscilloscope?

using an oscilloscope application on my computer through sound card.

[TheUnderTaker]

Thanks Raff

good luck you too.

[Carl-NC]

Using the oscope, you should be able to look at the output of the integrator stage and see a rising/falling level as a target is moved close to the coil. You should see even more change at the output of the final gain stage. Also, make sure your SAT is not too low, and you threshold is set properly.