transponder key fob projects?

[kevb]

Hi I am new to forum
Can anyone direct me to any transponder key fob projects?
Thank you

 

[House0Fwax]

Have a look at these two sites, hopefully they may be of interest.

http://jap.hu/electronic/codec.html
Infra/radio remote control encoder/decoder with PIC

http://www.hackersbench.com/Projects/ding-dong/index.html
Hacker's Bench : Wireless Doorbell Hacking

 

[kevb]

Hi thank you for the info but they do not use transponder technology
I am looking to construct a system for opening a gate at a local boating club
There are about 100 members.
I would like to use the cheap key ring transponders each having a different code
New transponders could be added or deactivated as new members join or expired members go.
We are using standard keys at the moment which is a pain not to mention the expense
With a system that I could construct would give a lot of satisfaction.
Regards

 

[evandude]

your wording is ambiguous. "Transponder" to me sounds like a remote control, which would explain the links in the first reply. What you're looking for is an RFID system.

Check out phidgetsusa.com, they sell USB RFID readers and all sorts of tags, including keychain/card/button/pill shaped, etc - with the USB reader you'd need to hook it up to a computer and let the computer handle the access control. You can also get RFID readers with an RS232 serial interface which would be easy to interface with a microcontroller if you want it to be a small standalone unit.

 

[Brevor]

Is this something like you are looking for ? I have used these before and they worked well.
They use RFID cards for access.


https://www.awid.com/solutions/products.aspx?id=MTAwMA==