RFID Reader

Hi all,

First time poster. I wanted to build an Arduino RFID door lock system. I live in an apartment building where I don't think I can install a reader on the outside of my door. Does anyone know if there's a reader I can get that will read the tags through the door/doorpost?


If your door is made of metal then you will probably have to read through the wall.

If you door is a wooden paneled door (roughly 1/2" thick) you can probably read right through the wood. Hollow-core (1.5") doors might be a problem.

maybe this article will help with setting it up http://hackaday.com/2012/05/27/reading-rfid-cards-from-afar-easily/.

Hi, Do some reading on RFID options; there are now several, from the older 125Khz with very short range, to some 13.56 Mhz and now even some up in the Ghz range like WiFi.


Hi Terry, Do any of these look reasonable for connecting to an Arduino and just reading back an NFC card serial number? Don't need to write, don't need any other data off the card. Thanks

http://www.alibaba.com/product-gs/503448728/13_56MHz_RFID_Reader_Module.html http://www.alibaba.com/product-gs/540371911/RDM880_low_cost_13_56MHz_RFID.html http://www.alibaba.com/product-gs/540834333/rdm880_reader_module_rfid_module_rfid.html http://www.alibaba.com/product-gs/346085048/30_OFF_13_56Mhz_ISO14443A_rfid.html http://www.alibaba.com/product-gs/236364007/3V_reader_module_rfid_reader_module.html http://www.alibaba.com/product-gs/501457517/13_56mhz_RFID_Reader_Modules.html http://www.alibaba.com/product-gs/515164362/RFID_Reader_Module_for_Product_Management.html http://www.aliexpress.com/product-gs/453708603-MF-30W-485D-Smart-Card-RFID-Reader-Module-With-Built-in-Antenna-wholesalers.html http://www.alibaba.com/product-gs/346091784/25_OFF_Mifare_Smart_Reader_Writer.html

Hi Robert,

This is available easily for $11 or less: http://iteadstudio.com/store/index.php?main_page=product_info&cPath=16&products_id=6

Comes with loop antenna.

They put out ASCII. Data Sheet: http://iteadstudio.com/store/images/produce/RFID/125KReader_U/RDM630-Spec.pdf

Cards and Tags are 50 cents.

13.56 Mhz is close-sensing, not at any big distance..

The ones I use are from stronglink. They have a real good customer service. They have many modules. Probably the one you'd like is the following because of its size and pcb integrated antenna.


I did not tested with doors. I've got sl031 and sl016. Stronglink provides any module with I2c xor serial interface. They are easy to use. They do not manage collision.

Thanks to you both. I will continue my research!

What is the implication of not managing collisions?

The collision occours when multiple rfid are detected by the reader in the same moment. The collision management provides some functions to read multiple rfid one by one. In your case it should'nt be important as you probably want just one rfid key be used at once.