Trouble with RDM6300 RFID reader


I’m having trouble to read 125kHz RFID tags using a RDM6300 RFID reader and an Arduino Duemilanove.

I bought this reader and these RFID tags.

I wired everything as described in several data-sheets and tutorials (e.g. - see below for wiring picture.

I used a really simple code to just get anything from the RFID reader but I receive nothing…
I move the tag above the coil in every kind you can imagine, but there is nothing in my serial monitor.

Different RDM6300 modules/coils were tested and also another Arduino. Same result.

Do you have an idea?

#include <SoftwareSerial.h>
SoftwareSerial RFID(2, 3); // RX and TX

int i;

void setup()
  RFID.begin(9600);    // start serial to RFID reader
  Serial.begin(9600);  // start serial to PC 

void loop()
  if (RFID.available() > 0) 
     i =;
     Serial.print(i, DEC);
     Serial.print(" ");

It was a simple issue. The seller on ebay sent me wrong RFID tokens (I guess 13 kHz instead of 125kHz).
I ordered another one which is 125kHz and it worked.


I think i am having the same problem. Is there a way i can check the tags i have to be sure they are not the 125 kHz tags?

I'm glad I'm not the only one with the same dumb problem. Except it was me ordering the wrong tags :frowning: