Struggle to read my custom implant

[lsergeev]

Hi, 3 weeks ago I got a custom implant based on Desfire EV2, so the same form factor as the FlexDF2.
But I have a problem: the reading distance is surprisingly low for a flex. I use it to access my work, and only 1 reader can read it.
Basically, the readers at work can read cards at 5-7cm (or 1.8 cheeseburger for Americans), but they can also read cards “through” 2 hands placed between the reader and the card. I’m amazed that a flex implant can’t be scanned, even though they detect my x-series on contact!
For my phone, for example (S21+), I have to remove the shell and rub it for 5 seconds.

Possible causes in my opinion:

• Manufacturing/conversion defect
• Implant damaged during fitting (unlikely, as before the implant was fitted, it scanned poorly through the simple sterile pouch) https://youtu.be/3rpn-8PlC0U?si=o8b5vVCoHdi_njKR
• You have to wait longer after insertion. It’s only been 3 weeks and it’s no longer inflamed. It’s fitted to the forearm just below the wrist.

[Equipter]

it sounds like it could be installed quite deep if its having range read problems, where is it installed and how deep is it?

also of note, the flexes do not advertise themselves as having the same read range as a CR80 format credential, physics beats out in this situation.

[lsergeev]

@Equipter

it sounds like it could be installed quite deep if its having range read problems, where is it installed and how deep is it?

Like you can see in the video, in the forearm below the wrist (at the same location that regular watches). I don’t know how deep it was installed, the pro who installed it is used to install flex implants

@Equipter

the flexes do not advertise themselves as having the same read range as a CR80

Yeah except the FlexNeXT, none of them can even approach CR80’s reading range, but I’m surprised that my xSeries implants can be read by the same readers contrary to the flex one

[Az_F]

I assume you have tried already but maybe it’s an issue with orientation and position, they are very important for getting a good read.

[lsergeev]

Yes I tried in every orientation for like 5-10 mins (until security guards came to ask me wtf I was doing)

[hoker]

Careful now, doing that got me fired from a corporate job before

[lsergeev]

Thanks for the advice, really. I’ll try to be discreet even if the system admin knows (but couldn’t register a FlexDF as a badge, hence why I had a custom one made).

[Pilgrimsmaster]

@lsergeev

Possible causes in my opinion:

I have a number of my own thoughts, some inline with yours, some not.

@lsergeev

Manufacturing/conversion defect

Always a possibility, though unlikely.

@lsergeev

custom implant based on Desfire EV2, so the same form factor as the FlexDF2.

There is a bit to disect here, if you’re willing to share the chip that was used that may help to diagnose your problem. For example, the actual FlexDF2 (of which I have one.) Requires a bit of power and good coupling in order to get a good read.

Using your diagnostic card may be a good idea, just to check the duty cycle.
a. to make sure it is constantly “looking” with constant power ( Generally different to a phone )
b. to see if the power increases ( LEDs on diagnostic card become brighter ) when a CARD is placed near it
c. to see if the power increases ( LEDs on diagnostic card become brighter ) when YOUR IMPLANT is placed near it

You mentioned you have tried all your orentations which is good, The ideal one would most likely be parallel to the antenna.

@lsergeev

Implant damaged during fitting

The use of metal tools is not advised and can void your Warranty.
In fairness the install didn’t look too bad ( To me, But Amal may have a different opinion, if he reads this, at around the 3 min mark )

@lsergeev

before the implant was fitted, it scanned poorly through the simple sterile pouch)

This can be by design, as the tuning changes when it is implanted and you read it though your skin, so it should be better tuned (Satur9 works some magic on the antenna design so this happens), HOWEVER, you won’t notice due to the trauma of the install, so you’ll need to wait the usually reccomended 2 weeks, which brings me to

@lsergeev

You have to wait longer after insertion. It’s only been 3 weeks and it’s no longer inflamed. It’s fitted to the forearm just below the wrist.

A couple of things here also

Watching the video

The installer was digging around with the forceps quite a bit to make the cavity, which will likely have caused some extra trauma, therefore likely increased you healing period.

The install appeared slightly deeper than I would have personally done, not to say there was anything wrong with it, but that depth won’t be helping.

Finally, the skin on the forearm is thicker than that on the back of your hands for example.

So MY OPINION

• A lot of trauma = longer healing, give it another couple of weeks to heal, and see how it goes.
• Use of tools to insert MAY have caused damage ( Possibly increased chance of Bio-fouling)
• The depth is not going to help
• The thicker skin is not going to help

In the mean time, do those Diagnostic Card tests
and wait…

[amal]

The above seems to show the use of forceps with teeth to handle the flex implant. This is a problem since the teeth will cut into the biopolymer and potentially compromise the integrity of the material.

Another question - did the artist autoclave the implant before installation, or did they drop it straight out of the gas plasma sterilization pouch provided on to the sterile field?

@lsergeev

You have to wait longer after insertion. It’s only been 3 weeks and it’s no longer inflamed. It’s fitted to the forearm just below the wrist.

This is likely. The bottom line is, you can’t tell when there is no longer any swelling… also read Swelling vs Inflammation … with the amount of trauma associated with the installation method, you may have to wait 6-8 weeks, or possibly longer, for all swelling to dissapate. My Apex Mega took 4 months for absolutely all swelling to go away. This is due to trapped coagulated blood surrounding the implant, which takes a very long time for the body to finally break up and remove… and the consistency of the dead blood itself does affect performance as well as push the surface of implant further away from the reader’s inductor coils… and sometimes getting a read vs not getting one is just a small matter of 0.25mm.

Bottom line, I don’t think your implant was damaged to the point where it was compromised… but if so, generally speaking performance will slowly decline over weeks or months until it is unreadable. This is typically due to the slow infiltration of fluids into the polyamide flex PCB itself, de-laminating it and acting as an electrolyte which detunes it… and finally it will result in basically a short circuit.

[lsergeev]

@amal

The above seems to show the use of forceps with teeth to handle the flex implant. This is a problem since the teeth will cut into the biopolymer and potentially compromise the integrity of the material.

This is one of the possibilities, and if it was damaged during installation, it’s probably the reason. I preferred to trust him because he’s used to installing all types of implant and has a good reputation…

@amal

Another question - did the artist autoclave the implant before installation, or did they drop it straight out of the gas plasma sterilization pouch provided on to the sterile field?

He took it out of the sterile pouch just before installation

@amal

you may have to wait 6-8 weeks, or possibly longer

performance will slowly decline over weeks or months until it is unreadable.

Okay, so I guess I’ll just have to wait, and contact the pro to find a deal if the implant turns out to be damaged.

[lsergeev]

@Pilgrimsmaster

Using your diagnostic card may be a good idea, just to check the duty cycle.
a. to make sure it is constantly “looking” with constant power ( Generally different to a phone )
b. to see if the power increases ( LEDs on diagnostic card become brighter ) when a CARD is placed near it
c. to see if the power increases ( LEDs on diagnostic card become brighter ) when YOUR IMPLANT is placed near it

I just did the test:

• the readers for which my implant doesn’t work, scan continuously at high power (LED flashes brightly)
• the only reader that works, scans continuously but at very low power (LED barely lit)?!? And the power doesn’t change when I approach the card or the implant.

[amal]

@lsergeev

he’s used to installing all types of implant

This makes sense because the technique he used would be typical for all kinds of silicone based implants designed to switch through a small opening in the skin and sort of expand under the dermis to create a shape like a star or a horn or whatever.

The problem with experienced artists with reputations is the same problem we have with medical doctors - they’re not often open-minded and learning new things and ignore instructions. Clearly they’ve never dealt with this kind of implant before and instead of learning how to do it properly, they relied on there existing skill set.

Still, I have my doubts that there was any significant damage done. It’s much more likely the problem has to do with swelling and positioning, for the possibility that the readers are doing some sort of magic chip checking or there’s some other interface problem between the implant and readers that is causing the problem.

[Equipter]

@amal

for the possibility that the readers are doing some sort of magic chip checking or there’s some other interface problem between the implant and readers that is causing the problem.

what chip was it? original post says its based on Desfire Ev2, if its a magic desire as far as I’m aware there is no magic check for those as they’re a super mega niche chip rarely seen used so not worth defending against.

if I had to guess it may be a timing problem, some emulator chips struggle with matching spec timings and if readers are particularly picky that could be whats causing it.

@lsergeev are the readers that work with it the same brand and model as the ones that don’t work with it? what brand readers are we talking about here?

also do you have a proxmark? it would be interesting to get a trace of the communications between the implant and the reader

do you have another one of the chips that you had converted? have you checked to see if that works in the situations where you implant isn’t working?

if it isn’t a problem caused by timings, as amal said it very well could be down to the healing. my own flex had good range the day it went in but since its been heavily reduced due to the underlying trauma that will resolve over time as it heals completely.

something that might be worth a try is a Resonant Repeater Sticker, Void found their arcade implant didn’t work on one reader and the sticker lens’d the signal exactly where it needed to be boosted for their implant to work

[lsergeev]

@amal

This makes sense because the technique he used would be typical for all kinds of silicone based implants designed to switch through a small opening in the skin and sort of expand under the dermis to create a shape like a star or a horn or whatever.
they’ve never dealt with this kind of implant before

He installs many silicone implants, but also DT implants. In the week he installed mine, he also did an apex flex and a payement conversion. He was recommended to me on a biohacker discord community

@Equipter

what chip was it

My bad, it was an EV1. An NXP Mifare Desfire EV1 4k (according to NFC Tools). It isn’t an emulator since desfire is impossible to copy due to encryption (if I don’t say anything stupid)

@Equipter

@lsergeev are the readers that work with it the same brand and model as the ones that don’t work with it? what brand readers are we talking about here?

The one that works is a gantner (GAT Vending 6100 BA). The other ones that don’t work are Stid (LXC-R) or SpringCard (Funkygate)

@Equipter

also do you have a proxmark? it would be interesting to get a trace of the communications between the implant and the reader

I have one, but never used it so it could be a good reason to unbox it

@Equipter

do you have another one of the chips that you had converted? have you checked to see if that works in the situations where you implant isn’t working?

I have a card with the same chip, as said in the first message it works well with the card and have good range (also can be detected through 2 hands or through the entire forearm)

@Equipter

something that might be worth a try is a Resonant Repeater Sticker, Void found their arcade implant didn’t work on one reader and the sticker lens’d the signal exactly where it needed to be boosted for their implant to work

I’ve considered this possibility, but sticking on 40 or so stickers is going to cost me a lot of money, and it’s going to be complicated in certain sensitive areas such as certain laboratories.

[Equipter]

@lsergeev

It isn’t an emulator since desfire is impossible to copy due to encryption (if I don’t say anything stupid)

magic chips emulate an official chip because they’re not that actual chip, you can get desfire magics with changeable UIDs that are technically emulator chips

you can copy desfire providing you can get the data off the original which most are unable to do due to the security but if you have provisioning access over the system you’d have the key & could do it, but yes in most cases they cant be copied

good to know its not a magic so that tosses it out the window

yah id just think its a healing situation, stay hydrated, massage the insertion site to break up building scar tissue