DIY Reader esp/arduino

Implantat reader
13.56 MHz
Rc522 read it, no range
PN532 have range of 5-10 mm
How is range on PN7150?

Has anyone found anything better?

DT sell 125kHz 12v DIY circuit/reader is LF reader Better for implants?

my test build
Reader Rc522
Coding in arduino

reads tag relay changes state
Like ignition mode


So far as LF goes, there’s the RFIDuino Arduino shield. Arduino’s are 12v tolerant. I got 25mm using that with a NExT.


Yes I have. I’ve done a lot of Arduino RFID installs.

Buy any RFID reader on Amazon that supports the Wiegand protocol that is compatible with 13.56MHz RFID. The Wiegand protocol will work on two Arduino GPIO inputs.

Note that the Wiegand protocol is 5 volts. This will work natively on any 5 volt Arduino. Most 3.3V boards can’t accept it without conversion. ESP32 has been known to “unofficially” accept 5V on its GPIO inputs, but I never rely on this (I just stick to 5 volt Arduinos for this).


interesting then there are very many different readers instead of the modules

I have one of the 7150 modules but at the time there wasn’t enough examples for me to work from. I’ll dig into it again soon

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That new Arduino Uno R4 is a pretty good option because it has native 5 volt I/O, but also has the option for WiFi if you want it to communicate.

Otherwise if you want to go minimal and talk with a Wiegand RFID reader, it would be a knockoff Arduino Nano plus one of those relay units depicted in the OP.

Spoiler, you’ll want to connect the D0 and D1 pins of the RFID reader, to pins 2 and 3 of the Arduino Nano (since these pins are the easiest for attaching “interrupts”… this is the simplest way to reliably receive messages in an Arduino using the Wiegand protocol.)

The protocol is very simple. It will transmit a series of pulses (typically 26 or 34) whenever a card swipe occurs… the D0 wire gets a pulse for a 0 bit, and D1 gets a pulse for a 1 bit… all of the pulses arrive in a fraction of a second. you simply decode the pulses and you’ll get the card number. Using “attach interrupt” to detect pulses instead of polling the pins, eliminates the chance of missing a wiegand pulse by not polling fast enough.

after you get a card number, the simplest thing to do is compare it with a hardcoded card number, and if it matches, open sesame for 1-3 seconds on whatever pin the relay connects to.


Do you think a small reader is better for 13.56Mhz implanted?

I don’t think the size of the reader matters so much as what the distance will be between your implant and the reader.

My favorite SMALL reader is the Drexia ones. They are tiny enough you can use a forstner drill bit to set them flush into furniture. Drexia’s readers come in multiple interface options but the most flexible interface option with an Arduino is going to be the RS232 version (not the “iButton”, “1-wire” or Wiegand versions) because you will get the maximum number of unique digits from the implant per scan, and it’s the simplest to read on an Arduino. Your best connection on a classic Arduino Nano or classic Arduino Uno is to wire the data pin to pin 8 and use “AltSoftSerial”, or if using the Arduino Uno R4, to pin 0 and use “Serial1”.

Here’s a link to a seller I’ve purchased from the past iButtons by TimePilot: RFID Readers scroll to the bottom of the page for the 13.56MHz readers.

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Also to answer whether LF/HF is better… LF has better range…

If you already have the implant, the reader you select must match your implant… the wrong one won’t respond at all.

If you have a dual implant like the combined NeXT implant that has both 125KHz T5577 (LF) chip as well as a 13.56MHz (HF) chip in the same implant… then you have the option of using either kind of reader.

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I started this a while back, maybe we can add it al together?

Good idea, I was just about to move this one BUT Your thread is nice and tidy, This one has some chatter on it already.

How about?

@chipguyhere follows your link

Fills this out


  • Name:
  • Picture:
  • Price (About/estimate)(before shipping and taxes):
  • Voltage:
  • Current consumption (resting):
  • Read distance:
    • With a full size card:
    • With a key fob:
    • With a glassie:
  • Implant tested :
  • Description and notes:

and links back to this thread for the extra info?

I’ve been tinkering with RFID readers myself, and I’ve found the PN7150 to have a decent range, typically around 5-10 mm, similar to the PN532. As for LF readers like the DT 125kHz DIY circuit, they tend to have a bit more range, especially for implants. Your test build sounds interesting with the Rc522 and Esp32 combo. How’s the coding experience been for you with Arduino? I’ve been playing around with similar setups for different projects.

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It is ok for me to move it

I have xmagic so dual like next

the coding can be a bit complicated to understand all the special characters and their function, but there is a lot of help on the internet

or you take the good stuff and cut into your thread so mine can be a bit of a trial and error thread.

so yours will be more informative and mine more discussion thread

What’s the range for a x-series? +/-?

I have used the readers from id-innovations
And very happy about them good read range for x-series +/- 20mm
Created my own antenna’s and got up to 40mm with the id-3