Whites Surf PI schematic

[6666]

Find the scheme and make SBG-PI. You will be pleased.

This project ?

http://www.geotech1.com/forums/showthread.php?18747-SBG-Pi-schematic&highlight=SBG-PI

[scs]

Find the scheme and make SBG-PI. You will be pleased.

[taluch]

Hello
I have read on your forum your link to the plummeting functionality of the Surf 1.2 detector. I am from the Czech Republic, we bought a board on Ebay, built a detector but it is very bad. It has a small depth range and when zooming to the metal does not amplify the signal, and about 3cm from the target with the signal will lose.
I do not have much knowledge in this area, but unfortunately, nobody has told me what I should do. Measurements on integrated circuits and transistor voltage are correct,
The coil should also be good. The only part that is replaced is MPA13.mam instead of MPSA14 because I did not reach it. May I ask you Would you please me
I can not advise anyone who would have an oscilloscope. I'm sorry to bother you but look for advice as it goes. English is probably too bad, I translate it with a computer. Thank you
Talužek

[Hoot]

My bad - I said Surf pi 2 I meant 1.2

[6666]

Anyone tired using Mylar "emergency" blankets?

The problem with them is continuity , if you hold the blanket up to the light you will see along the corners of the folds they wear thin and go open circuit , you need to check a few with a MM to get a good continuity.

[Sean_Goddard]

SWEET Homefire. Many thanks.

[homefire]

Yep some work better then others. Try this stuff to keep contact ! Works for me. https://www.ebay.com/i/182258631705?chn=ps

[Sean_Goddard]

Anyone tired using Mylar "emergency" blankets? They're huge and you should be a large number of coils out of one. If it works then maybe making a sandwich with the coil in the middle would give good shielding. The problem is making contact. I have used silver conductive epoxy and glued the drain wires in place AFTER securing the foil I used in the housing.

I just don't understand why so many people are having problems with the SM PI kit from Silverdog.

I bought one, built it EXACTLY as the instructions said, hooked up a 300uH 10" (21 turns of 16AWG wire) coil with shielding (remember the gap or you wnd up with a shorted turn) stuck 12 V into it and it worked perfectly. I can pick up an 18ct wedding band at around 14" in air (after CAREFULLY adjusting delay and threshold).

More than happy with the results. So much that I sold my CS4PI as the kit of the SMPI is much better.

The only thing I can think of are;

1) Poor soldering

2) Putting the WRONG parts in locations.

3) Poor component handling (Anti-Static workbench or mat is a GOOD IDEA)

4) Fake or poor-quality components

5) Overheating components when soldering

6) NOT cleaning the board properly after building. I ALWAYS use isopropyl alcohol and distilled water in a 50/50 mix in an ultrasonic bath with a heater and clean the boards for 2 minutes at 50 degrees C.
BE CAREFUL with this as the boiling point of this mix is 80 degrees C. DO NOT SMOKE OR ALLOW SPARKS ANYWHERE NEAR, hence EVERYTYHING must be grounded or you will be playing a harp. Best done outdoors.

[homefire]

Welcome: Surf PI 2 ?? Who has those for offer ?

[Hoot]

Good morning, just lurking, ordered a surf pi 2 kit - waiting to start assembly.

[scs]

With dd coils you can make very good discrimination ...

[Tim]

Hello guys
I have a little problem with my SurfPi (Silverdog Kit): the detector in the air work well, but if i bring the coil to the ground, receive sound even if it does not detect metals (false signal).
Do i need to adjust the trimmers better?
Thanks for your help

peppe I ended up using ML commander and coiltek 11DD on my SMproDD. DD arrangement should be easy to modify. Shielded coils. Nearly all our ground in Oz is highly mineralised. The SMpro (tacoma56 ebay) also has external delay- this could be adapted to the Surf temporary or permanent to help resolve the problem. I have also had success using mylarised plastic (powdered milk packet) as a unwired shield on my home-made coils (full sheet across bottom). Also I started a thread here regarding adapting a Vsat arrangement to the surf, receiving some very helpful replies. Though I have not tried this yet.
Sascho (scs) answers are also very helpful. I think this man is a genius. There are a few threads here regarding modifications to the Surf sound if you do an advanced search. From memory the simplest options were a transistor change and/or spkr output from other side of transistor, or a 64ohm speaker. Others may correct me on this.

[scs]

Sound -a better option...

[scs]

[scs]

The problem is a long sound signal and a short pause. This increases the consumption when there is a signal.