Snifer XR71p

[Geo]

Hi. I finished the XR71p and i can give us the results from test. The control became in the laboratory where exist a lot metal objects and thus i could not regulate the sensitivity in biggest. I used 4 coils so i will give us the results for every coil.All the coils are 10in (25cm).

Coil uH coil R(Ohm) 2Euro 100 drx soda can problems
(25mm) (30mm) (330ml)
220 1.2 22 cm 25..26 cm 45..50cm
600 8.2 25 27 60 Unstable
300 0.8 30 35 90 Very Unstable
500 1.3 27 30..32 65..70 very stable

I have not changed the damping resistor (2.2K). I measured the coils with an analog instrument so i am not so sure for the precision.

[ma330]

xr71p

hi
i build sniffer xr_71p. this circuit have very parasite
you can help to me for this problem . ??????

[Geo]

hi
i build sniffer xr_71p. this circuit have very parasite
you can help to me for this problem . ??????

Hi. Tell me more about parasites and the conditions that you test the detector. You must try it out of home and not near electric wires. Begin with low sensitivity and low power. Good luck.