Need this circuit printed circuit board

[cristi71]

poland detector

I replaced the ua741 lf356 and go but with very very low sensitivity. 356 lf stand out .. thanks for always less coil data. I think the problem is to lf356'll try somewhere else to change the configuration

[cristi71]

poland detector

finally go. I put ua709 with slight changes and it works exactly as it is played on you tube. is built on a plate to pass test.next pcb. Thank you for your help. coil has 28 turns on a 20cm diameter. all the best!

[cristi71]

poland detector

hello, does anyone how discrimination scheme this unit? well, Cristi

[bernte_one]

hello christi

could you post or lin k some images of finished soldered board and which partlist do you use the one from the pdf from (side before) or have you changed some parts?

[cristi71]

poland detector

demonstration here. http://www.youtube.com/watch?v=4VBjCd-8_iI .I'll come back with changes in hours. only good

[cristi71]

poland detector.

D1 substitute with 2x1n4148 antiparalel, R9 chance with 100 ohm, replace C9 (SHORT), and operational amplifier. i used lm308.

[cristi71]

poland detector

in attachments . sorry is in paint..

[silverdog]

Lucaslab Pi Pcb's

I had a few pcb's of this board made by a local UK company to see if maybe they could compete with my China supplier - No basically but they are quite good boards anyway

I have 8 available at just £5 if anyone is interested

http://www.silverdog.co.uk/shop/inde...tegory&path=35

[koko22]

Please help ,i build Poland detector
when i test it work with sound continuing i move piece of metal above the coil the sound stop the device works in reverse

[mikebg]

Please help ,i build Poland detector
when i test it work with sound continuing i move piece of metal above the coil the sound stop the device works in reverse

Koko, adjust more precisely the bias (TUNE) with P1, P2, PR1.

[koko22]

Thanks mikebg for you reply i still have Problem with this pcb i make this pcb by corldraw form the Magazine ,i Replacement T1 by BD907 and IC1 by TL081 Because i didnot find it

[koko22]

This the file pcb

[eessoo]

Hi Guys
i made this circuit but it doesn't work
i can hear the humming sound of the coil but the speaker doesn't make any sound
and i made the modification i removed the capacitor (short) and changed the diodes and the lm308

[eessoo]

pictures

[cristi71]

not recommend changes I made. (lm308 with lf357) can be a sample. lf357 have lf356 otherwise use sensitivity drastically decreases.