FlexNExT smart bracelet project

That was my point and question

Did he just make a stun gun, or did he actually calibrate it to get proper effect

Theses some science on the voltage and cycle rate (hertz? Not sure if the same) in addition to barbs that maximize distribution

Slowmo guys have a great video, and you can see the muscle activation sweep across his back

Also interestingly tasers are legal in my state with proper paperwork, and stun guns are always illegal

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I got one of the parts I’ll be repurposing for the bracelet in the mail today: a Proxgrind ChameleonTiny Professional, supplied by the good people at KSEC Solutions.

Why that thing you ask?

Well, it has everything I need: it’s not much bigger than a piece of candy, it’s extremely light, it runs on battery, it can output an unmodulated 13.56 MHz carrier wave with a decent amount of power, the field can be turned on and off, it can be controlled over BLE, and the firmware is open-source. It really has all the features I need right out of the box.

Check out its performances. Not too shabby for a sugar lump:

All it needs is an external antenna and some code from yours truly, to transmit messages from a cellphone.

As for the bracelet proper, I’m waiting for a batch of PCL plastic to start shaping that - hopefully nice-looking, but I wouldn’t be too hopeful, as I’m not a very artsy kind of person.


I’m not asking, because I also have one, I got my Chameleon Tiny Professional from Sneak Technology ( $80 for BLE $60 for non-BLE ) Good for the Asia Pacific area, and KSEC for Europe, I believe Lab401 are also in Europe, but personally I"m not a 401 fan… Go KSEC if you are in Europe
I carry mine in my bag with a Keysy ( HF - LF Bases Covered )
Cool, clever simple bit of kit.

Looking forward to seeing your project.

Also your doNExT looks awesome with it :+1:

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Simple yes, but surprisingly full-featured for such a tiny device.

Yeah it lights up like a christmas tree now that it’s not completely covered in collagen gunk anymore.


Hey @anon3825968, is it clear what nfc reader chip they’re using on the ChameleonTiny Professional, or is it unbranded? I’m trying to tell from this image but can’t.

The large chip on the right is definitely a Nordic Bluetooth SoC (probably nRF52840), but what is the model number for the large chip on the left?

I have no idea. But there’s a simple protocol in the firmware that I should be able to implement to talk to the thing over BLE. It connects already, it’s just that it won’t answer simple text commands because I have to encapsulate them in their custom frame format.

Isn’t the chip just visible on the back of the device? It looks like it’s encapsulated in clear resin, should be pretty easy to visually inspect it.

For that my friend, I’d have to crack out the reading glasses and I haven’t bothered to do that yet. Without them, all I know is there’s clear resin on top of something dark.

I’ll have a look when I get home. Right now I’m stuck at the office for emergency bug fixing.

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Oh yeah, no worries. I didn’t expect you to sort it out right this second! If you get a chance later, I would appreciate it. If you don’t have a microscope at home you could always use a magnifier app

I have a USB microscope webcam thing - somewhere.



So a xmega 128a4u sweet thank @Pilgrimsmaster

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Awww, thanks @Devilclarke , you are also sweet :wink:


Sooo many repliable pearls of wisdom here.
Actually far too many to reply, so I’ll abstein from most! :wink:
But thanks for all that sharing!

That beauty should do the perfect trick for a belt buckle I was thinking about.

It’s a nice device but the BLE functionality that I need is completely undocumented, and it’s giving me a lot of trouble. I can connect to it and list its characteristics, but that’s as far as I’ve been able to go so far. I have no time to dive into the code of the Android app that serves as BLE “reference API” because of work, and so for the time being, the project is sadly put on hold.

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I’ve ordered one as well.
When it gets to me and I can make time to mess around with it I’ll post any results here.


Just a little extra info I stumbled across that may be of interest to you…or not


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