125kHz range, or am I just unlucky

So, I’m putting together an access control system at work, with the ultimate goal of being able to use it with my NExT (not implanted yet).

I have a bunch of 125khz readers knocking around the factory. A cheapo USB HID device, a bodet time attendance clock, 3 off unbranded security keypads and a weigand keypad for the access control itself.

I can’t check these with my NExT yet, it’s still in it’s syringe. What I can do is wave my diagnostic card and key fob field detectors over them.

Surprisingly, the only one that gets a response is the USB HID.

With a standard rfid tag, they all trigger at approx 20mm from the reader.

Does this bode well for my NExT?

So with your NExT you should have gotten xFDs.

You can test the readers with them, they are little LED chips in a typical xSeries form factor.

If it lights up, even just a little, it should be ok.

EDIT: Ok I can’t read, sry.

Yeah, I have the credit card style and the newer keyfob type from the NExT kit. Neither gives me even a little glow:(

They both work with the HID though.

is that because you only

I could be wrong, but it sounds like you need to move slower and closer to the reader.
The diagnostic card should light up no problem.
If you haven’t tried it yet, touch the card to the readers to ensure that there is power to it, incase it has been disconnected or yet to be connected? Is that possible? It sounds like the system has not yet been set up.
Are you doing a bench set up?
Are you wiring up a new system or upgrading an old one?

The xFDs will come in handy :smiley: when you are trying to find the best orientation to present your NExT.

This is probably just putting out more power

So at work we have some readers that behave super strange. They seem completely ‘dead’. Does not react at all to the diagnostic card or the xFD.
Nothing lights up.

But they work with my NeXT :sunglasses:

Here’s an image of them.

So since you’re going to install the NeXT anyway, my advice is: wait and see if you can get a read after installation

Done the slow and steady pass over the readers. Moving 3mm at a time to ensure I’ve checked every spot.
Card and the XFds have been tested from 0-20m distance from the readers.
Everything is powered up and working. The access control is under test on a bench before being installed. I can enrol standard rfid fobs and trigger an unlock with no issues.

But they work with my NeXT

Work easily, or a bit picky on position?

I’m trying it with one of these

I can get a good reading anywhere within the black bezel if I use our usual rfid keyfobs. Just nothing with my diagnostic card or XFd.


I have a NExT and it’s not really great for the LF part. I can’t use it on anything but my PM3 and even than it has to be just on the right spot. The HF part is somewhat better, but my VivoKey is so much better.

I’m thinking about taking out the NExT and getting something else, but not sure what. I like the idea to have two chips(LF and HF) in one tag, but the flexMN is pretty pricy and bulky.


Only tried twice, as they’re not installed in the building I usually work from.
However I had no problem reading the NeXT.
(a lot harder to read it on the proxmark3)

Finally got around to checking this with an implanted NExT rather than just my field detectors.
Everything works great ,:wink: I expected to have to search around to find the best position, but it looks like I’ve got lucky with placement. I’ve hit it first time every time so far.
Looks like it’s just very tricky getting a read off either of the field detectors

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LF is often quite forgiving, mostly because most of the readers they’re used with are used for access control and put out plenty of power to get an easy read. It’s also why LF glass implants suck ass with most lower-power, USB tabletop readers - including the PM3.