Any sensor that can detect mettalic objects and magnetic objects

Is there any sensor available for detection of mettalic objects

you can make your own metal detector..

hai,can u help me out in developing one

check one over here..
http://www.uashem.com/pageid-287.html

Simple BFO metal detector Circuit

This simple metal detector requires only a handful of components and an evening's work. Built around a cmos4011 IC, is very robust and versatile. The 250 kHz reference oscillator is built with two gates (U1/1 and U1/2) C1, R1 and P2. The search oscillator uses only one gate (U1/3) two capacitors and the search coil. The output of the two oscilators are fed to the fourth gate acting as a mixer, filtered with C4 then amplified with U2.

After assembly adjust the volume control (P2) for comfortable volume and turn P1. The pitch will get lower until it disappears. Continuing to rotate P1 in the same direction will cause the pitch to rise again. The point at witch the pitch is the lowest and disappears is called "zero beat". If you can not get this zero beat frequency for the entire turn of P1 you may have to select different values for C1.


Parts list:

* U1: CD4011
* U2: LM349
* U3: 78L05
* R1: 2.2k 5%
* P2: 4.7k lin.
* R3: 330k 5%
* R4: 270k 5%
* R5: 1k 5%
* C1: 390pF (NPO)
* C2,C3,C4: 10nF
* C5: 10uF 16v electrolytic
* C6,C8: 220 uF 16v electrolytic
* C7: 100uf 16v electrolytic
* C9: 100nF ceramic
* P1: 4.7k log
* L1: 22cm in diameter with 14 turns AWG 26
* K1: SPDT toggle switch
* J1= Headphone jack 1/4 or 1/8 inch
* Other parts: 9v battery connector, speaker or headphones
please check for CD 4011 http://www.onlinetps.com/ViewItem.php?ItemID=39
for LM78L05 http://www.onlinetps.com/ViewItem.php?ItemID=97
To Convert AWG to SWG please VISIT http://www.geocities.com/tpsbpl/swg_awg_calculator.htm