VERY SIMPLE PI METALDETECTOR

[Max]

hi people. I still remember its BT2 project, very simplest you may even imaginate yourself. but I do not see the link in Net... and are not able give you recommendations in this matter.

How many dang shahab you added there ?

[Fred]

Fred , What your looking for is very Rare now!!! I found a couple of items , for now here is one you know of , it is the national semicondutor LM318H.

Hi Eugene,
Thanks!
As it is used for a power supply, it ios not so clitical, as long as the case
is the same .The LM318 can be a good idea.

Regards,
Fred.

[Fred]

How many dang shahab you added there ?

Actually this is the real one, the US have removed the others from pictures

[kt315]

How many dang shahab you added there ?

[JC1]

best

Hi KT315,

You are the best !!!

Too funny.

[Unregistered]

hi people. I still remember its BT2 project, very simplest you may even imaginate yourself. but I do not see the link in Net... and are not able give you recommendations in this matter.

KT315, thanks!!!
Very simple!!

[amtech2005]

VERY SIMPLE PI METAL DETECTOR

KT315, I know this is off the subject , but can you tell us more about the two Russian photo's you posted above . Are they Copies of "Rare Expensive" one's. Or just very common one's from Years Ago ???..........Thank-You ....Eugene

[kt315]

why rare expensive? I do not think. btw you can go to Moscow and see/buy all these banners in shops at Arbat street. all are done by best way for foreign tourists. no problem with this is now and was always. in capitol.

[Unregistered]

after to have studied the several circuits, I have decided to make the surfmaster, indeed much easy, only problem with the TIP32 does not work because much hot and does not find the metals, l' I have replaced with IRF9640 and works enough well, sin that does not go much deep one, 10 european cents 10-12 cm depth in air, with coil from 20cm and 27 turns.
exist a way in order to increase the performances?
Excuse my english

[Max]

after to have studied the several circuits, I have decided to make the surfmaster, indeed much easy, only problem with the TIP32 does not work because much hot and does not find the metals, l' I have replaced with IRF9640 and works enough well, sin that does not go much deep one, 10 european cents 10-12 cm depth in air, with coil from 20cm and 27 turns.
exist a way in order to increase the performances?
Excuse my english

10cents at 10-12cm is no good... is not descent performance for it on 20cm coil...but something like 60's BFO stuff...

You can push it well above... say on the 25cm range for 10cents.

Reduce the 1st delay and increase the TX on time.

Kind regards,
Max

[kt315]

unregistered, keep us in course of your project stages. schematic with all updates of gurus you'l find here attached.

yours

[Unregistered]

thanks KT315,
I have replaced R6 with 390 OHM and IRF9640, the other modifications I cannot make them because I have already developed the board.