Whites Surf PI schematic

[T-bass]

oxigeno07m

hi few days todos.hace surfmaster complete the project, namely the oxigeno07m.el detector works very well but I have some problems, do not use or do not see any utility to the threshold and delay potentiometers, if I turn the threshold tone is heard the speaker and whether the delay shift in the position according to leave it detects more or less, around 15-20cm to 20cm with a coil of copper wire of 0.4 mm.Me like to add to this project sensivilidad adjustment the speaker and whether the delay shift in the position according to leave it detects more or less, around 15-20cm to 20cm with a coil of copper wire of 0.4 mm.Me like to add to this project sensivilidad adjustment and a discriminator, but I have trouble understanding the scheme that brings the mods.estaria very grateful if you help me, or better yet, if you can get a pcb of surfmaster to have all the settings, I mean sensivilidad, threshold, delay, discriminator , Volume antemano.Un ...... thanks greetings

[T-bass]

oxigeno07m

someone help me

[cavinr]

hi cordius ,please send the master of new pcb. and also side place component .

thanks

I hope it work. here is new pcb

[remus_im]

this detector could be used in soil with pottery fragments?
sorry for my bad english

[TH Jim]

Could be possible, my surf pi reacts to bricks buried on the beach.

[konan]

Complete detector. It works well except that I have two problems.

1) Review with the photolith pen, the tracks are very close to each other.

2) The detector after 15 minutes it begins to make strange noises.

3) I can not put 12V, starting a sound impossible to be silent. I have to feed 11V to operate.

Anybody can help me find out what is going on?
a copy of it.

not corect

[Wilson]

Tradução do português para inglês

Hello, I built the Surf-Pi and replaces by NE5534 TL081 "Remove P1 ofset" also replaced by LM358N TL082.

Replaces
R18 47K to 820K
R9 1M to 2M
R2 3K3 to 10K "553Hz"
R6 390R to 680R "Damper"

Inserted in series "R22 100K" potentiometer 100K "GAIN setting outside panel"

P4 eliminated and Speaker, one installed at the site Twiter Piezo transformer internal low power.

21cm wire coil 19 turns 0.5 mm

Also rode a 18cm x 18cm square coil 20 turns 0.5 mm wire worked very well, I'll ride with PVC pipes and connections 1 / 2 "rod and 3 / 4"

The operation with the coil in the air and the exchange of the components mentioned above was very good, I know that IC is not exactly the same but worked better than the original with more sensitivity.

OBS:Not tested in field

Wilson

[Falcon]

hi Wilson!

you are Brazilian? (I am)
you made these changes greatly improved performance? (depth of search)
I have a project that finds a £ 1 coin (real) to 37cm (not yet finished this, but the inventor of the project says yes)
yours is better?

[Wilson]

Google Tradutor


Hello Falcon, but I am Brazilian! the project that you're riding seems to be better, I've researched and hardly reaches a depth that you mentioned, hopefully that works.
25cm in the air I got a gold ring on the threshold of audio.
Which project are you riding? please let me know.

[Falcon]

Who sent me the project (SURF PI) was "Dirceu"which also participates in this FORUM (http://www.geotech1.com/forums/showt...t=13810&page=8), but he made some changes (do not ask me how and where because I'm an amateur at it, hehehe) if you want I can send you by email.

[Wilson]

Falcon OK, please send me by email.
Thanks.

[A Gumby]

Surf PI coil drive simulation

Here a Surf PI coil drive simulation file to use with the the free TINA-TI analog simulator found here:

http://focus.ti.com/docs/toolsw/fold...t/tina-ti.html

Use it to play with coil variables and damping resistors.

[Noemio]

The way I chose dumping resistor

To chose the proper dumping resistor, I use a (power) potentiometer and a series resistor for the minimum value (let’s say 150 ohm) instead of R6.
Put the probe of the oscilloscope (yes, an oscilloscope is needed…!) at the output of U2, pin 6 of NE5534, and gradually lower the potentiometer value until all the spikes disappear. See the image below.
Disconnect the potentiometer, measure his actual value and replace it with a fixed value power resistor.
That’s all.

[Alexismex]

Very nice animation and complete info for the novice ,thank you noemio for this good post.
alexis.

[A Gumby]

To chose the proper dumping resistor, I use a (power) potentiometer and a series resistor for the minimum value (let’s say 150 ohm) instead of R6.
Put the probe of the oscilloscope (yes, an oscilloscope is needed…!) at the output of U2, pin 6 of NE5534, and gradually lower the potentiometer value until all the spikes disappear. See the image below.
Disconnect the potentiometer, measure his actual value and replace it with a fixed value power resistor.
That’s all.

As a matter of fact, that's exactly what I'd planned to do to check the accuracy of TINA-TI. I'll be using a pot with a low value resistor in series.