Clone PI-W small detection range

[MDfanatic]

Hello fellow MDers, I purchased a Clone PI-W (or sort of) assembled board from newhobby but all the coils I've built (all of them around 400-430uH) do not seem to have a decent detection range.
My latest coil (60cm - 13 or 14 turns [can't remember exactly] 0.5mm litz wire) with the barrier at full will detect a shovel (on air) at 70-80cm and I think this number is ridiculous for such a big object, even with the barrier at full.

I've also built a 60cm coil with 1mm litz wire but the detector wouldn't work with the specific coil (at startup all LEDs were lit and wouldn't go off until the "tuning" was done).

Unfortunately the soil in my place is considered "hot" and when the barrier is lower than full it beeps all over the place, at least for Clone PI-W.

Should I throw the board outside the window or should I try something else? Is Clone PI-W suitable for big coils or am I wasting my time?

[kt315]

Clone-PI is a clone of Schedrin's Tracker/Koschej. yes, it works with any coil. better with big.
a barrier is SAMPLE DELAY. there is not second sample taken, for GND balance. good toy to begin to learn something new in life.

[MDfanatic]

kt315 thank you for the information, I was expecting bigger detection range for the shovel with 60cm coil.
I don't want to waste my time with toys, I think Clone PI-W is not good for the depth I am looking for (80cm-1.30m on soil for big objects, like an ammo crate).

What MD can I built that can reach that depth on soil without too much noise or hitting rocks?

[waltr]

The Hammer Head works well ans with My PIC code to do the three sample GB works even on hot soil.

[MDfanatic]

waltr thank you for your input, the problem is I'm pretty much a newbie into schematics (and totally ignorant when it comes to full-manual detectors) and it will take me weeks (at best) before I finish a working (and error-free) PCB and set it up correctly..
Besides that, I don't have an oscilloscope or PIC Programmer and information on HH2 is very scarce so I guess it's not a project I can lay down right now because all I have is a soldering tool, flux and solder :/

[waltr]

Lots of details on my HH2 here:
https://www.geotech1.com/forums/show...ake-on-the-HH2

However, it does sound like you are not yet ready for this one.

If you need a PI detector for hot ground (Ground Balance adjustment) then none of the Simple PI detector will work.
This includes the MiniPulse Plus (MPP), the Barracuda, Surf, etc. projects found on Geotech unless you add circuits to do GB.

[Vadim18]

Same problem...
I built Clone PI-W last summer, worked on the desktop extremely steadily, but ... the field tests really weren't very good. I work with a 40X60 cm coil, I also tried a 15 cm coil, and in both cases I have a strong reaction to the ground, and I can't even retune ground with the reset button. I'm using 1.22 m firmware, with slow dynamic mode (no option), maybe I need older firmware with static mode. But I already finished Delta Pulse (Superdec 79 ) last year, with more good impressions than bad.
Try another firmware or, if you are unlucky, use it as a reference unit or pinpointer.
But, i recomend you to build something with ground elimination try HH2 from waltr.

I also designed the PCB to fit in a small case, but firmware...

[kt315]

first of all, you need to shield an enclosure. second, put a pot in preamp pin, look schematic. by this pot you have to tune detector on maximal
sens. it is famous trick in russian part of the net.

the detector on pics is not mine. you have to see the pot on the box.

[kt315]

this page from old deleted site. i converted it in DJVU format, for universal reading. read FAQ part.

[MDfanatic]

Actually my Clone PI-W has nothing to do with the schematic you uploaded kt315, it is a board that I've bought (pre-assembled) from an e-shop.

I don't even know If I can even call it Clone PI-W because it is run by Atmega8 and it has 2 X LF353N and 1 X 4066, no XTAL or anything else on the board..
I guess it is a modified version of the Clone PI-W and I don't think there is any solution in the detection range, the current draw is 65-75mA based on the manufacturer.



I don't have a shielded coil or enclosure but even on bench tests it really sucks big time, with a 60cm coil it can detect a 35cm oven-pan at 80-90cm with the barrier setting on 2/6.
During the initial start up all LEDs go out so I guess this MD it just isn't up to the task.

P.S: It's only been a month since I started learning about schematics, components etc so please be kind If I make any mistakes.

[kt315]

do you need my long story telling why Andrej Fiodorov made a clone of Andrej Schedrin's Koschej-PI?
that you now has like CLONE-PI.
i said about just PREAMP, not about whole schematic.
read my posts more attentionally.
---
During the initial start up all LEDs go out so I guess this MD it just isn't up to the task.

LEDs are intensive meter. they do not have to light if no target.

[MDfanatic]

If you mean the 1k pot that is next to the two 1N4148 diodes (look at the picture in my previous post), I have already maxed it and the detection range remains almost the same with very little difference.
I have built 6 different coils with different sizes and turns but almost all coils gave the same result.

If there is metal near the coil when it starts, some LEDs will stay ON and the sensitivity is reduced, that is why I said all LEDs go off when it starts.
I'm sorry If I frustrate you but you are very experienced in electronics and I am still an infant so I must learn how to run before I learn how to walk!

[kt315]

ask schematic from the seller. ebay messages with links are banned but you can give him your email address.
try.

[MDfanatic]

kt315 thank you for your patience and I appreciate your help tremendously, I bought the board from e-shop (not eBay) and I doubt the seller will provide a schematic but I will give it a try although I believe I'm just wasting my time with this MD.
I think I'll build the felezjoo pi smd version i've made and let's hope I can get a decent sensitivity without too much noise.

[kt315]

I'm just wasting my time with this MD.
---
my first TRACKER-PI worked good. i know a potencial of this schematic. follow recommendations from geotechers.