Mosfet switching time

[PierreJ]

I was making multiple pulse induction circuits using IRF9630 p-channel mosfet but the range is very low (couple of centimeters for 10*10*10 cm hollow iron cubes), even after trying multiple coil designs and 3S lithium batteries
I suspect the problem is that the mosfet doesn't cut the current...

[anil.berk]

Hi I am trying to build MPP REV E step by step. It seems okay to me until I reached step 8.

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Step 1: Check U3 pin 4 for -5V

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Step 2: Check TP7 for +5V

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Step 3: Tx driver pulse
I adjusted pulse period to 1 ms (1KHz) and pulse width to 100 us approximately....

[Atul Asthana]

Wondering if a PI detector of the kind described below is feasible:
1. A normal PI transmission in the coil. (The transmission pulse may also be shaped)
2. The response/decay is sampled at 5 micro seconds (or any suitable speed), at least 10 bits (or more), 64 samples (this should be enough)....

[Faouzi77]

Hi to all
About pulse induction metal detectors
What is the best device to make? more stable. Suitable for deep and reliable research on gold
Thank you

Source code files for ITMD Editions 1 & 2

The following zip file contains both the C source code and hex files for the PI2, PI3, and PI4 projects.



The following zip files contains source code for the Coil Calculator.

Tcl/TK Version:

JavaScript Version: ...

[Elliot]

Powerful NEW pulse induction detector that is ideal for finding lost treasure, coins, gold & silver jewellery, relics and small to large gold nuggets!

Features:

• Pulse induction technology (1,600 pulses per second)
• Fastest sampling time ? 6uS for outstanding detecting depth
• High

...

[haseeb zaib]

Hey guys

I am reverse engineering this PI metal detector but I am stuck in this part of the circuit. I am calling it 4 stage amplifier but mainly this is the portion where all the sampling is being done. Before getting to a part where I am stuck, let me explain a circuit a bit, upper side...

[SaltyDog]

Hi everyone,

Welcome to my new project. (This thread is a continuation of comments I made on the Pickini Metal detector thread, which has been of great inspiration for this project).

After trying many metal detector circuits over the years, I have determined that the Pulse...

[captainart3000]

Fully waterproof and ready to dive deep. Up to 100yards.
Automatic ground balance. Everything automatic.
Rechargeable batteries.
Device is very stable and not affected by saltwater. Works great on black sands. Extensively tested in carribean and on Lake Tahoe.
Currently...

[ionut_mtb]

Good quality metal detector. I attached some pictures and technical specs. I do not have schematic. It is non motion md, volume and sensitivity pots, nice connectors, rubber gaskets for battery compartment and front panel, nice strong shaft (half aluminum half fiberglass).

I did some...

[ionut_mtb]

Hello,

I have some questions regarding this detector.
- where is dumping resistor for the coil? It does not seem to be inside the shrink tube. Coil inductance (pulse diver 950) measure 0.224mh (hi reading) and 292uh(low)- which one is the real value? (i don't have multimeter with...

[CatchMe]

I am using PI basic circuit only RL with clamping diodes with R before and I make an ARDUINO comparator and I start counter till the comparator signal changes, I compare the voltage from clamping diodes and compare it with pot voltage in mv. It gets 12 cm range for a metal object 10 cm 10 cm plate....

[anto22]

Hi

[Connor]

My question is how do metal detectors using the PI technique ground balance ? is there a foolproof method used by most, or are there many various methods ?

I am currently in the preliminary stages of building the TWINLOOP TREASURE SEEKER, this design uses two coils to negate effect of mineralisation...

[scrungy_doolittle]

All the PI detector information I see, involves generating a pulse (which is a ringing damped sinusoid) and damping it so it doesn't ring. Then extracting information from the decay slope.
This is leaving valuable information behind. This post should be considered prior art for anyone thinking...

[Tinkerer]

With a traditional PI we measure the amplitude of the target response.
Much is to be gained by measuring also the target TC.
The best way to do this would be by digital signal processing. However, I found that a programmer needs to understand a function well in order to write good code...

[Janne]

Hi,

I've been thinkin of building my own metal detector for a little while now. After browsing through a whole bunch of different designs, I decided to start with Mark Stuart's PI detector.

http://www.geotech1.com/cgi-bin/pages/common/index.pl?page=metdet&file=/project...