Self triggering PI receiver

[Davor]

Once I decided to try minipulse and finally try some PI, I realised that my "concealed carry detector" goal may be realised as a PI. The whole idea is to build a separate Tx and a separate Rx with wireless headphones interface, so that I may fit the Rx in a shoe with battery and all, and carry a Tx coil in the most inconspicuous way I can think of. The only problem with this approach would be triggering the Rx by a flyback pulse over the induction linkage, sort of 2 boxx way. That way I'd be able to simply take a casual stroll, but in fact scan the ground for goodies. I could even hold some odd stick in my hands and pretend to go dowsing.

I'll post ideas for this solution here as they come to me. Please feel free to post your solutions of this kind.

[sinclairuser]

hi davor, why not have something like a mono loop built into the heel of a shoe use a non motion design, then as you walk it detects, or maybe a small dd built into the sole, the detector could be the size of a ciggarete packet you could strap this to your ankle, if you ran the headphone lead up your leg you would not need wireless phones.
a bit 1960's james bond but what the hell, i certainly think non motion is the way to go, the constant movements may look daft with motion mode.

[Waikiki_Sweep]

- it was in news few years ago.

I guess box starts vibrating when slipper hits the target.

Probably it is easy to hide monocoil, power supply and vibrator from cellphone into slipper. So nothing will show that it is MD inside.

MD boots have to be patented and sold to military. Why not to warn and prevent army personnel from stepping on land mines by sound, vibration or electric discharge.

Monocoil may works too. Also if RX and TX separated they have to be fixed mechanically or moving TX against RX will trigger false signals.

[WM6]

I tested last year "Vibro Shoe Detector" for beach, made out of Nokta pinpointer (in vibro mode).

To much sensitive for all those crappy targets on beaches.

[sinclairuser]

as an idea its worth investigating, for treasure hunting, for mines not so much as any warning would be too late if you think about it.
step,click,buzz-BOOM.

[Waikiki_Sweep]

as an idea its worth investigating, for treasure hunting, for mines not so much as any warning would be too late if you think about it.
step,click,buzz-BOOM.

Why not? You can choose where to put your foot not only by looking on the ground but hearing what is inside.

At least when someone build that slipper MD we can ask to check is there enough time to move foot aside without stepping on target once it beep.

[sinclairuser]

because the thing about landmines is often when you know its there its too late, also would you walk in a mine field with a detector on your foot?.
if your foot does not trigger it the detector could.

[Silver Dollar]

Why not a Mono coil worn as a belt around your waist? (I'm not sure it is a healthy idea).

Or you could have one on your head and one around your waist like Aziz's Top Hat...

Remote triggered RX is going to be difficult, you could find the front of the flyback and
sample at a fixed interval after that, it should be the biggest signal around...

[Waikiki_Sweep]

Why not a Mono coil worn as a belt around your waist? (I'm not sure it is a healthy idea).

Or you could have one on your head and one around your waist like Aziz's Top Hat...

Should be out or range. If only you are not detecting something flying in air around your head.

> if your foot does not trigger it the detector could.

What a sadistic mind invented mines triggered by metal detectors and how they going to clean their own minefields if there is no way to use metaldetector. OK. WE can shoot that MD slippers on mind field from the shelter to let all mines to explode.

[sinclairuser]

i'm not suggesting metal detectors are a bad idea, i'm suggesting WALKING AROUND A MINE FIELD IS, if no one else an see that i give up!
having a buzzing detector strapped to your foot is a different thing to it being on the end of a meter long pole.

[Davor]

hi davor, why not have something like a mono loop built into the heel of a shoe use a non motion design, then as you walk it detects, or maybe a small dd built into the sole, the detector could be the size of a ciggarete packet you could strap this to your ankle, if you ran the headphone lead up your leg you would not need wireless phones.
a bit 1960's james bond but what the hell, i certainly think non motion is the way to go, the constant movements may look daft with motion mode.

Mainly because of the batteries size and weight, but there are also other reasons more intimately related to PI. I'm not fond of the idea of keeping a high voltage source THAT near my body.
I also expect mineralisation to play a somewhat less dominant role if Tx is supplied via a large diameter coil away from the surface.

As a sidenote, this arrangement will make possible a huge single turn Tx loop of many meters in diameter to encompass an area I wish to examine in depth, and I mean real depth, so not only a concealed carry is on my mind

[Waikiki_Sweep]

i'm not suggesting metal detectors are a bad idea, i'm suggesting WALKING AROUND A MINE FIELD IS, if no one else an see that i give up!
having a buzzing detector strapped to your foot is a different thing to it being on the end of a meter long pole.

Common.. Do not be so serious... I am just joking.

Sure nobody will ever build or use such device on minds field.

All that ideas of "concealed carry detector" are good to squeeze some fun from it.

[Waikiki_Sweep]

As a sidenote, this arrangement will make possible a huge single turn Tx loop of many meters in diameter to encompass an area I wish to examine in depth, and I mean real depth, so not only a concealed carry is on my mind

Significant is expected with such configuration. Also you will need a powerful batteries or generator to power the TX.

[Davor]

Maybe not. I could go for an energy saving solution with Tx, and because I have a completely separated Rx coil, I can also sample earlier and recover some losses.

[Waikiki_Sweep]

Lets roughly compare 20 turns coil with square 25 x 25 cm area with square 5 x 5 meter one loop TX.

Using "Tx loop of many meters in diameter" with same current and only one loop you will decrease magnetic field strength in

20 x 5 x 4 x 5 x 4 = 8000 times.

If you can better to hook it to your car battery to rise current and keep magnetic field up.