PI. Question

[bulsack]

Hi Everyone! An old man from my town will show me the location where his great grandfather supposedly witnessed this. A few turkish men ,fleeng from the advancing russan army buried about 8 leather bags full of gold coins at about 1 meter depth. Due to erosion I assume now it's at up to 2 meters deep. Since it's not in a metal container I'm positive the White's TM 808 or a Garret GTI 2500 with the 2 box attachment will not be able to locate it.
My question is, will a pulse induction do the job?
BTW I had a EM-83 (geo-western) and my electronics guy totally messed it up before we realised that the batteries were deffective. All I have left from it are the two coils (TX&RX). I could sell them if somebody's interested.

[WM6]

An old man from my town will show me the location where his great grandfather supposedly witnessed this.

Tipical "Golden dream". For Golden dream you do not need PI or some others kind of detector. All you need is just dream on.


Interesting, you know how deep (1m) gold was burried, but you do not know where ? Is your grandfather saw this burial or not??? If not, how they know how deep? If yes, how they did not know where? If know where why they did not dig treasure?

Still answer: in very rare ideal soil circumstances, proper PI with proper coil can detect a bunch of gold coins even close as deep as it detect in air test. Why? Because of (usualy different) coin orientation regarding search coil in both test.

[Rov]

Hi bulsack,if you got a reasonable location for your treasure,an have a system in place to grid it as a pro prospector ,or treasure hunter would do,hire a new Minelab 4500 or borrow for a time .Damb good Pi for depth in the real world an easy to use,is probably all you will need . forget the contraptions an gadgets.for the time. Do a good overall preliminary search with one of these. You may be surprised?
For dedicated deep search on a large target.Ground Pen. Radar unit is the only way.for bigger$$$$. 2box seems to have little true following,value or development ,these days for deeper search.Try as you may though?
I know in my preliminary search.Id do a Minelab 4500 over all my search territory First!
Cheers! Rov

[bulsack]

A friend of mine has the GPX 4500 and it doe's not seem to go very deep. It could barely detect a jar full of coins at 2 feet. We played with all the adjustments. Maybe we are doing something wrong? Anyway he is too lazy to use it often and learn how it responds to deep targets.

[Rov]

Try larger Coils?Some pros use these on the back of Quad Bikes in a small trailer even.just hand laid loose.on a timber/wooden or poly pipe frame.
Just do a good preliminary over all your known ground first.before you get more advanced,satisfy your mind its not in your first 1metre of depth.First. Good Luck!

[Harp]

good day!

Can someone explain a couple of basis in relation of Pi devices.
On the test plate I made pulse generator, including the MOSFET and the coil. I stop here.

I used the power adapter from the printer, which has all the necessary voltages, but relatively low amperage.
I measured him the power consumption of about 100mA ... BUT - it was fake, the power electronics has imposed amperage!

Later I connected the battery and read the consumption of 2.5A
The wire diameter is 0.4mm, induction around 250uH, resistance around 3-3.5 ohms.

I tried it with two different MOSFET which I found near at hand: 2SK701 (front SDG) and STP3020L (front GDS)

So the question: if the MOSFET short-circuiting the coil with power, how is it possible that the PI devices are spending about 100mA?
Obviously I merged something wrong, but I do not see what it would be ...

Thank you!

[Carl-NC]

When you short the coil there can be a high current -- say, 2 amps -- but you turn it on only briefly and periodically, so the average current over time is much lower. Use a large tank cap next to the coil switch to avoid having the main power circuit supply the instantaneous amps.

P.S. -- it's best to post a new thread when you have a new question.

[kt315]

try to increase the pulse width from your 50us (0,00005 second, 5/100000 second) to 1ms (1/1000 second) and you will see nice smoke from MOS-FET.
good experiment for learning. mystery smoke is always living in the electronics. sometimes anybody looks it really...

[Harp]

Thank you, I'll replace the thread