RFID tag ring

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Hey all,
I'm quite interested in the whole RFID reader thing (thinking of setting up my car doors and ignition, and my house with RFID readers for locks initially), especially the part of it where I don't have to carry around anything extra and annoying.

I like the idea of the hand implant, but I don't know if I'm ready to get something quite so permanent yet. I was thinking about it, and I thought the best alternative might be to set up a ring on my right hand (I'm right handed) with a built in RFID tag!

I'm thinking of getting a signet ring (http://www.allmoviereplicas.com/Pirate-Signet-Ring-Sterling-Silver.html) of some sort and building in a Black Pill tag (http://www.trossenrobotics.com/store/p/4897-Black-Pill-Tag-17mm-.aspx) into it.

I'm wondering how I'd go about doing this - I'm guessing the best idea is to get a jeweler to take apart the ring, put the tag in, and put it back together. Would the metal cause an interference though? If so, would a small hole in the side of the ring allow for the signal to be carried?

If anyone's got any experience in this area (or has an educated guess, or general suggestions with my ideas :P) I'd love to hear!

Thanks all :).

- Whitey

Edited by amal - 10 July 2010 at 9:10pm

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Whitey Members Profile Send Private Message Find Members Posts Add to Buddy List Newbie Joined: 14 June 2010 Location: Australia Status: Offline Points: 1	Post Options Post Reply Quote Whitey Report Post Thanks(0) Quote Reply Topic: RFID tag ring Posted: 14 June 2010 at 12:10pm
	Hey all, I'm quite interested in the whole RFID reader thing (thinking of setting up my car doors and ignition, and my house with RFID readers for locks initially), especially the part of it where I don't have to carry around anything extra and annoying. I like the idea of the hand implant, but I don't know if I'm ready to get something quite so permanent yet. I was thinking about it, and I thought the best alternative might be to set up a ring on my right hand (I'm right handed) with a built in RFID tag! I'm thinking of getting a signet ring (http://www.allmoviereplicas.com/Pirate-Signet-Ring-Sterling-Silver.html) of some sort and building in a Black Pill tag (http://www.trossenrobotics.com/store/p/4897-Black-Pill-Tag-17mm-.aspx) into it. I'm wondering how I'd go about doing this - I'm guessing the best idea is to get a jeweler to take apart the ring, put the tag in, and put it back together. Would the metal cause an interference though? If so, would a small hole in the side of the ring allow for the signal to be carried? If anyone's got any experience in this area (or has an educated guess, or general suggestions with my ideas :P) I'd love to hear! Thanks all :). - Whitey Edited by amal - 10 July 2010 at 9:10pm

amal Members Profile Send Private Message Find Members Posts Visit Members Homepage Add to Buddy List Admin Group Joined: 22 November 2005 Location: United States Status: Offline Points: 2061	Post Options Post Reply Quote amal Report Post Thanks(0) Quote Reply Posted: 21 June 2010 at 7:33pm
	Metal does cause interference, but that's what LF 125KHz tags are designed for, mitigating interference caused by metal and liquids. The fact is, you'll typically get better read range from a tag that uses a flat plane antenna vs a cylindrical coil (like glass tags) because most reader antennas are also flat planes. If the pill tag gets 3 inches with a specific reader, embedding it in a piece of jewelry will probably reduce the range to less than one inch, but it should still work. Only by trying it will you find out if it works well enough for you.
	Amal ;) www.amal.net

amyj Members Profile Send Private Message Find Members Posts Visit Members Homepage Add to Buddy List Newbie Joined: 15 October 2006 Location: United States Status: Offline Points: 13	Post Options Post Reply Quote amyj Report Post Thanks(0) Quote Reply Posted: 10 July 2010 at 7:59pm
	I've made several pieces of jewelry using that 17mm EM4102, including a signet ring: http://amyjohnston.com/gallery.php?id=17. So yes, it can be done. I doubt, however, the ring you're considering will work for the following reasons: 1. Tag size vs. workable space. The tag is a true 17mm. I've taken some down to somewhere around 16mm, I seem to recall, before exposing the antenna, and you'd want enough plastic still around the antenna so moisture doesn't kill the tag at some point in the future. The website states "The ring measures approximately 19.5 mm (3/4") tall, 15.3 mm (just under 5/8") across the face of the signet and 3.7 mm (just under 3/16") at the back of the band. 2. More importantly, having metal across the read face of those tags reduces their read range to less than 0". It's possible a different reader, potentially the new RedBee, would solve this problem, as all my EM41XX readers are the original Phidgets model specified in RFID Toys. I'm looking forward to experimenting with the RedBee for this very purpose. 3. Finally, and critically, the skull and crossbone would have to be riveted through the antenna inside. I've done extensive research into where one can and can't drill through that tag, and assure you that drilling through anywhere but the very edge will kill it dead dead dead. Trust me on this one. I've killed at least 20 of these tags trying. Having said all that, your mileage may vary. Let me know if you have any further questions. ^.^
	Amy J. http://www.amyjohnston.com

amal Members Profile Send Private Message Find Members Posts Visit Members Homepage Add to Buddy List Admin Group Joined: 22 November 2005 Location: United States Status: Offline Points: 2061	Post Options Post Reply Quote amal Report Post Thanks(0) Quote Reply Posted: 10 July 2010 at 9:16pm
	Amy, great post. Thanks for the detail! One thing that might be possible is embedding an IC and winding your own antenna coils as an integrated part of the jewelry, rather than embedding a manufactured tag. Have you worked with winding your own coils before? You can also purchase pre-wound coils from companies like DigiKey and EM Microelectronic if the thought of winding coils makes your eyes gloss over (mine do when I think about it).
	Amal ;) www.amal.net

amyj Members Profile Send Private Message Find Members Posts Visit Members Homepage Add to Buddy List Newbie Joined: 15 October 2006 Location: United States Status: Offline Points: 13	Post Options Post Reply Quote amyj Report Post Thanks(0) Quote Reply Posted: 12 July 2010 at 1:56am
	ooo0o. I've been wanting to get into coil winding awhile now. I'd need to wind my own, I suspect, as I'd want them to be silver or gold rather than copper. The last time I looked into doing this (a few years ago,) I couldn't find any comprehendible reading materials about antenna design, tuning, etc. Do you have any recommendations?
	Amy J. http://www.amyjohnston.com

amal Members Profile Send Private Message Find Members Posts Visit Members Homepage Add to Buddy List Admin Group Joined: 22 November 2005 Location: United States Status: Offline Points: 2061	Post Options Post Reply Quote amal Report Post Thanks(0) Quote Reply Posted: 01 August 2010 at 10:19am
	A lot of the text covering black magic resonant antenna design can be found via Google... mostly in PDF format. I have a few gems I might be able to dig up and send to you.
	Amal ;) www.amal.net